Sample records for instabile arteriosklerotische plaque

  1. Ergebnisse der operativen Versorgung instabiler pertrochantärer Femurfrakturen mittels DHS und T-Platte

    Microsoft Academic Search

    N. Geissler; O. Meffert; A. Stapel; H. Heymann

    1994-01-01

    Zusammenfassung  Die dynamische Hftschraube (DHS) der AO ist ein bewhrtes Osteosynthesemittel bei stabilen Frakturen. Die Versorgung instabiler Frakturen bereitet hingegen Probleme, da es aufgrund des Schraubengleitprinzips zu einer erheblichen lateralen Dislokation der Fragmente kommen kann. Steht alternativ kein anderes Operationsverfahren zur Verfgung, kann die Belastungsstabilitt der DHS durch eine lateral aufgesetzte T-Platte verbessert werden. In vier Fllen konnte primre Belastungstabilitt erreicht

  2. Nonlinear Studies of FarleyBuneman waves Linear theory gives conditions for the onset of an instabil

    E-print Network

    Oppenheim, Meers

    1 Nonlinear Studies of Farley­Buneman waves Linear theory gives conditions for the onset of an instabil­ ity and characteristics of the initial growing waves but can­ not explain saturation or provide developed to explain saturated FB waves. Hamza and St.­Maurice [1993a, b] proposed a strongly turbulent mode

  3. Nonlinear Studies of Farley-Buneman waves Linear theory gives conditions for the onset of an instabil-

    E-print Network

    Oppenheim, Meers

    1 Nonlinear Studies of Farley-Buneman waves Linear theory gives conditions for the onset of an instabil- ity and characteristics of the initial growing waves but can- not explain saturation or provide developed to explain saturated FB waves. Hamza and St.-Maurice [1993a, b] proposed a strongly turbulent mode

  4. Histopathology of plaque rupture.

    PubMed

    Ravn, H B; Falk, E

    1999-05-01

    Plaque disruption occurs during the development of atherosclerotic lesions. During certain circumstances it may result in thrombosis and subsequent development of acute coronary syndromes. Several characteristics of the plaque appear to be associated with plaque disruption, including a large lipid rich core, superficial plaque inflammation, and a thin fibrous cap. The importance of these and other plaque components are discussed in this article. PMID:10384825

  5. Carotid Plaque Hemodynamics

    PubMed Central

    Harloff, Andreas

    2012-01-01

    Internal carotid artery (ICA) plaques constitute one major source of retinal and cerebral brain embolism. Current guidelines recommend optimal treatment of cardiovascular risk factors and recanalization based on the degree of ICA stenosis. However, ICA plaque composition, motion, vascularization, and local hemodynamics have only received limited attention as potential and independent risk factors for plaque rupture. The European Carotid Surgery Trial (ECST) showed an increased risk of stroke recurrence even in moderate stenosis if the plaque surface was ulcerated in angiography. Further indicators of plaque instability and thus vulnerability were established by native or contrast-enhanced two-dimensional duplex ultrasound, CT, and MRI. Due to high soft tissue contrast, multi-contrast MRI seems to be ideally suited to identify plaque compositions that are prone to rupture, although data from large clinical trials proving the independent predictive value of plaque morphology are lacking. The role of cardiovascular risk factors for atherosclerosis of the common carotid artery is well established. Nevertheless, little is known concerning the impact of local hemodynamics on plaque development, progression, and rupture. Wall shear stress, the friction force acting on the endothelium of the vessel wall, was shown to be able to induce local atherosclerosis and vulnerable plaques in animal models. Plaque movement and deformation was limited to investigations using ultrasound in order to identify plaques at risk. Similarly, models to calculate tensile plaque stress seem to be able to identify peak mechanical stress acting on plaque surfaces that make such regions susceptible to rupture. In this review, current evidence regarding the correlation of plaque location, composition, and local hemodynamics at the carotid artery bifurcation will be presented. Moreover, the potential benefit of a future comprehensive and individual risk assessment will be discussed. PMID:25187766

  6. [Diet and plaque].

    PubMed

    Banoczy, J

    1989-06-01

    In summary, many sugar substitutes have a direct effect on dental plaque formation and, therefore, also an indirect effect on hard tooth substance. Short-and long-term clinical studies have shown that xylitol reduces dental plaque. Short-term clinical tests have also demonstrated that sorbitol reduces plaque formation, probably due to retardation of acid formation. With time, this effect, however, diminishes due to adaptation of the microorganisms. Streptococcus mutans count and acid formation in dental plaque are favourably influenced by sugar substitutes, especially by the consumption of xylitol. The effect of sugar substitutes on dental plaque plays an important role for the anticariogenic and caries-reducing mode of action. The development of both caries and periodontal diseases can be favourably influenced by reduced plaque formation. PMID:2635961

  7. Proteomic analysis of atherosclerotic plaque.

    PubMed

    Porcelli, B; Ciari, I; Felici, C; Pagani, R; Banfi, C; Brioschi, M; Giubbolini, M; de Donato, G; Setacci, C; Terzuoli, L

    2010-05-01

    Proteins play a fundamental role in the formation and progression of plaque, but proteomic analysis of plaque as a whole is difficult, due to its heterogeneous cellular composition and an abundance of plasma proteins. Several approaches to this problem are reported in the literature; they include proteomic analysis of vascular tissues, analysis of proteins released by normal and pathological arterial walls, proteomic analysis of vascular cells and proteomic analysis of blood. In a previous study, we proposed a new strategy for studying of proteome of plaque, which permits to select the proteins exclusive to plaque by the constructing of a reference synthetic gel. In the present work, we matched the spots of the reference synthetic gel with the spots of a pool of carotid plaque, in order to select only spots exclusive to plaque from the 2-dimensional electrophoresis of the pool of plaque. We selected some spots between those exclusive and identified them by mass spectrometry. Some proteins identified are involved in transport, others take part in elimination of toxic radicals, others are metabolic enzymes or structural proteins. This study represents an example of application of the new approach which we have proposed: the reference gel of proteome of plaque permits to select, on every sample of interest, only the spots exclusive to plaque; once selected, spots can be identified by mass spectrometry and, being typical of plaque composition, could represent novel markers of lesions and vascular risk. PMID:20005669

  8. Proteomic analysis of atherosclerotic plaque

    Microsoft Academic Search

    B. Porcelli; I. Ciari; C. Felici; R. Pagani; C. Banfi; M. Brioschi; M. Giubbolini; G. de Donato; C. Setacci; L. Terzuoli

    2010-01-01

    Proteins play a fundamental role in the formation and progression of plaque, but proteomic analysis of plaque as a whole is difficult, due to its heterogeneous cellular composition and an abundance of plasma proteins. Several approaches to this problem are reported in the literature; they include proteomic analysis of vascular tissues, analysis of proteins released by normal and pathological arterial

  9. Routes to chemical plaque control

    Microsoft Academic Search

    D. Cummins

    1991-01-01

    A logical approach to the prevention of periodontal disease is through excellent supragingival plaque control. Such control is not generally achieved by mechanical oral hygiene procedures alone. Thus, there is a clear rationale for the use of antiplaque agents to augment mechanical means. The principle routes to chemical plaque control are to prevent colonization of the tooth surface, to inhibit

  10. Purine bases and atheromatous plaque.

    PubMed

    Terzuoli, L; Marinello, E; Felici, C; Frosi, B; Setacci, C; Giubbolini, M; Porcelli, B

    2004-01-01

    In this work we determined hypoxanthine (HX), xanthine (X), uric acid (UA), allantoin (ALL) and free radicals in atheromatous plaques to improve the comprehension of oxidative stress, a phenomenon which characterizes the evolution of atherosclerotic lesions. Carotid artery plaque were obtained from subjects undergoing endoarterectomy. Pulverized plaque, extracted by water, was used for analysis of oxidative stress factors (allantoin, uric acid, xanthine, hypoxanthine, free radicals). The peroxidation UA-->ALL was very high in the plaque, as was the level of free radicals. The results show that oxidative degradation of nucleotides, such as LDL oxidation, plays a specific role not only in the progression of atherosclerotic lesions but also in the advanced plaque. PMID:16857104

  11. Disappearance of La Caille Plaque

    NASA Astrophysics Data System (ADS)

    2010-04-01

    A bronze plaque erected to the memory of N.-L. de La Caille near the site of his observatory in Central Cape Town, has been stolen by metal thieves. It was designed by the famous architect Sir Herbert Baker.

  12. Pioneer F Plaque Symbology

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Pioneer F spacecraft, destined to be the first man made object to escape from the solar system into interstellar space, carries this pictorial plaque. It is designed to show scientifically educated inhabitants of some other star system, who might intercept it millions of years from now, when Pioneer was launched, from where, and by what kind of beings. (With the hope that they would not invade Earth.) The design is etched into a 6 inch by 9 inch gold-anodized aluminum plate, attached to the spacecraft's attenna support struts in a position to help shield it from erosion by interstellar dust. The radiating lines at left represents the positions of 14 pulsars, a cosmic source of radio energy, arranged to indicate our sun as the home star of our civilization. The '1-' symbols at the ends of the lines are binary numbers that represent the frequencies of these pulsars at the time of launch of Pioneer F relative of that to the hydrogen atom shown at the upper left with a '1' unity symbol. The hydrogen atom is thus used as a 'universal clock,' and the regular decrease in the frequencies of the pulsars will enable another civilization to determine the time that has elapsed since Pioneer F was launched. The hydrogen is also used as a 'universal yardstick' for sizing the human figures and outline of the spacecraft shown on the right. The hydrogen wavelength, about 8 inches, multiplied by the binary number representing '8' shown next to the woman gives her height, 64 inches. The figures represent the type of creature that created Pioneer. The man's hand is raised in a gesture of good will. Across the bottom are the planets, ranging outward from the Sun, with the spacecraft trajectory arching away from Earth, passing Mars, and swinging by Jupiter.

  13. Progress in atherosclerotic plaque imaging

    PubMed Central

    Soloperto, Giulia; Casciaro, Sergio

    2012-01-01

    Cardiovascular diseases are the primary cause of mortality in the industrialized world, and arterial obstruction, triggered by rupture-prone atherosclerotic plaques, lead to myocardial infarction and cerebral stroke. Vulnerable plaques do not necessarily occur with flow-limiting stenosis, thus conventional luminographic assessment of the pathology fails to identify unstable lesions. In this review we discuss the currently available imaging modalities used to investigate morphological features and biological characteristics of the atherosclerotic plaque. The different imaging modalities such as ultrasound, magnetic resonance imaging, computed tomography, nuclear imaging and their intravascular applications are illustrated, highlighting their specific diagnostic potential. Clinically available and upcoming methodologies are also reviewed along with the related challenges in their clinical translation, concerning the specific invasiveness, accuracy and cost-effectiveness of these methods. PMID:22937215

  14. Ultrasound Tissue Characterization of Vulnerable Atherosclerotic Plaque

    PubMed Central

    Picano, Eugenio; Paterni, Marco

    2015-01-01

    A thrombotic occlusion of the vessel fed by ruptured coronary atherosclerotic plaque may result in unstable angina, myocardial infarction or death, whereas embolization from a plaque in carotid arteries may result in transient ischemic attack or stroke. The atherosclerotic plaque prone to such clinical events is termed high-risk or vulnerable plaque, and its identification in humans before it becomes symptomatic has been elusive to date. Ultrasonic tissue characterization of the atherosclerotic plaque is possible with different techniques—such as vascular, transesophageal, and intravascular ultrasound—on a variety of arterial segments, including carotid, aorta, and coronary districts. The image analysis can be based on visual, video-densitometric or radiofrequency methods and identifies three distinct textural patterns: hypo-echoic (corresponding to lipid- and hemorrhage-rich plaque), iso- or moderately hyper-echoic (fibrotic or fibro-fatty plaque), and markedly hyperechoic with shadowing (calcific plaque). Hypoechoic or dishomogeneous plaques, with spotty microcalcification and large plaque burden, with plaque neovascularization and surface irregularities by contrast-enhanced ultrasound, are more prone to clinical complications than hyperechoic, extensively calcified, homogeneous plaques with limited plaque burden, smooth luminal plaque surface and absence of neovascularization. Plaque ultrasound morphology is important, along with plaque geometry, in determining the atherosclerotic prognostic burden in the individual patient. New quantitative methods beyond backscatter (to include speed of sound, attenuation, strain, temperature, and high order statistics) are under development to evaluate vascular tissues. Although not yet ready for widespread clinical use, tissue characterization is listed by the American Society of Echocardiography roadmap to 2020 as one of the most promising fields of application in cardiovascular ultrasound imaging, offering unique opportunities for the early detection and treatment of atherosclerotic disease. PMID:25950760

  15. Application of the gingival contour plaque index: six-month plaque and gingivitis study.

    PubMed

    Scherl, Dale S; Bork, Kim; Coffman, Lori; Lowry, Stephen R; VanCleave, Misty

    2009-01-01

    The Gingival Contour Plaque Index (GCPI) is a recently introduced and validated method of measuring plaque accumulation in dogs. It focuses on plaque accumulated along the gingival margin. Plaque accumulation in this area leads to gingival inflammation and, potentially, periodontitis. A 6-month plaque and gingivitis study was conducted to demonstrate the clinical research application of the GCPI, and to ensure that documented quantification of plaque-reducing efficacy could be related to a reduction in gingivitis. Advantages of the GCPI method are the ability to quantify plaque accumulation in an awake dog with fewer research personnel and more efficient time usage. PMID:19476084

  16. Purine Catabolism in Advanced Carotid Artery Plaque

    Microsoft Academic Search

    C. Felici; I. Ciari; L. Terzuoli; B. Porcelli; C. Setacci; M. Giubbolini; E. Marinello

    2006-01-01

    This study was carried out on carotid artery plaque and plasma of 50 patients. We analyzed uric acid, hypoxanthine, xanthine, and allantoin levels to verify if enzymatic purine degradation occurs in advanced carotid plaque; we also determined free radicals and sulphydryl groups to check if there is a correlation between oxidant status and purine catabolism. Comparing plaque and plasma we

  17. Human Carotid Plaque Calcification and Vulnerability

    Microsoft Academic Search

    Carl-Magnus Wahlgren; Wei Zheng; Wael Shaalan; Jun Tang; Hisham S. Bassiouny

    2009-01-01

    Background: Inflammation is a key mechanism in human atherosclerotic plaque vulnerability and disruption. The objective was to determine the differential gene expression of pro- and anti-inflammatory factors in the fibrous cap and shoulder region of noncalcified and calcified carotid endarterectomy plaques. Methods: Thirty carotid endarterectomy plaques were classified as type Va (noncalcified, n = 15) and type Vb (calcified, n

  18. Do Plaques Rapidly Progress Prior to Myocardial Infarction? The Interplay Between Plaque Vulnerability and Progression.

    PubMed

    Ahmadi, Amir; Leipsic, Jonathon; Blankstein, Ron; Taylor, Carolyn; Hecht, Harvey; Stone, Gregg W; Narula, Jagat

    2015-06-19

    There is a common misperception in the cardiology community that most acute coronary events arise from ruptures of mildly stenotic plaques. This notion has emanated from multiple studies that had measured the degree of angiographic luminal narrowing in culprit plaques months to years before myocardial infarction. However, angiographic studies within 3 months before myocardial infarction, immediately after myocardial infarction with thrombus aspiration or fibrinolytic therapy, and postmortem pathological observations have all shown that culprit plaques in acute myocardial infarction are severely stenotic. Serial angiographic studies also have demonstrated a sudden rapid lesion progression before most cases of acute coronary syndromes. The possible mechanisms for such rapid plaque progression and consequent luminal obstruction include recurrent plaque rupture and healing and intraplaque neovascularization and hemorrhage with deposition of erythrocyte-derived free cholesterol. Moreover, recent intravascular and noninvasive imaging studies have demonstrated that plaques which result in coronary events have larger plaque volume and necrotic core size with greater positive vessel remodeling compared with plaques, which remain asymptomatic during several years follow-up, although these large atheromatous vulnerable plaques may angiographically seem mild. As such, it is these vulnerable plaques which are more prone to rapid plaque progression or are those in which plaque progression is more likely to become clinically evident. Therefore, in addition to characterizing plaque morphology, inflammatory activity, and severity, detection of the rate of plaque progression might identify vulnerable plaques with an increased potential for adverse outcomes. PMID:26089367

  19. Bacterial sex in dental plaque

    PubMed Central

    Olsen, Ingar; Tribble, Gena D.; Fiehn, Nils-Erik; Wang, Bing-Yan

    2013-01-01

    Genes are transferred between bacteria in dental plaque by transduction, conjugation, and transformation. Membrane vesicles can also provide a mechanism for horizontal gene transfer. DNA transfer is considered bacterial sex, but the transfer is not parallel to processes that we associate with sex in higher organisms. Several examples of bacterial gene transfer in the oral cavity are given in this review. How frequently this occurs in dental plaque is not clear, but evidence suggests that it affects a number of the major genera present. It has been estimated that new sequences in genomes established through horizontal gene transfer can constitute up to 30% of bacterial genomes. Gene transfer can be both inter- and intrageneric, and it can also affect transient organisms. The transferred DNA can be integrated or recombined in the recipient's chromosome or remain as an extrachromosomal inheritable element. This can make dental plaque a reservoir for antimicrobial resistance genes. The ability to transfer DNA is important for bacteria, making them better adapted to the harsh environment of the human mouth, and promoting their survival, virulence, and pathogenicity. PMID:23741559

  20. Mechanisms of plaque formation and rupture.

    PubMed

    Bentzon, Jacob Fog; Otsuka, Fumiyuki; Virmani, Renu; Falk, Erling

    2014-06-01

    Atherosclerosis causes clinical disease through luminal narrowing or by precipitating thrombi that obstruct blood flow to the heart (coronary heart disease), brain (ischemic stroke), or lower extremities (peripheral vascular disease). The most common of these manifestations is coronary heart disease, including stable angina pectoris and the acute coronary syndromes. Atherosclerosis is a lipoprotein-driven disease that leads to plaque formation at specific sites of the arterial tree through intimal inflammation, necrosis, fibrosis, and calcification. After decades of indolent progression, such plaques may suddenly cause life-threatening coronary thrombosis presenting as an acute coronary syndrome. Most often, the culprit morphology is plaque rupture with exposure of highly thrombogenic, red cell-rich necrotic core material. The permissive structural requirement for this to occur is an extremely thin fibrous cap, and thus, ruptures occur mainly among lesions defined as thin-cap fibroatheromas. Also common are thrombi forming on lesions without rupture (plaque erosion), most often on pathological intimal thickening or fibroatheromas. However, the mechanisms involved in plaque erosion remain largely unknown, although coronary spasm is suspected. The calcified nodule has been suggested as a rare cause of coronary thrombosis in highly calcified and tortious arteries in older individuals. To characterize the severity and prognosis of plaques, several terms are used. Plaque burden denotes the extent of disease, whereas plaque activity is an ambiguous term, which may refer to one of several processes that characterize progression. Plaque vulnerability describes the short-term risk of precipitating symptomatic thrombosis. In this review, we discuss mechanisms of atherosclerotic plaque initiation and progression; how plaques suddenly precipitate life-threatening thrombi; and the concepts of plaque burden, activity, and vulnerability. PMID:24902970

  1. The relevance of Randall's plaques

    PubMed Central

    Strakosha, Ruth; Monga, Manoj; Wong, Michael Y. C.

    2014-01-01

    The pathophysiology of nephrolithiasis is not fully understood. The pioneering work of Alexander Randall in the 1940s sought to clarify our understanding of stone formation. This review traces the inception of the theory of Randall's plaques and the refinement of the hypothesis in the early days of kidney stone research. It then reviews the contemporary findings utilizing sophisticated investigative techniques that shed additional light on the pathophysiology and redefine the seminal findings of Dr. Randall that were made 70 years ago. PMID:24497683

  2. Thermal study of vulnerable atherosclerotic plaque

    E-print Network

    Kim, Taehong

    2009-05-15

    . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1. Clinical significance of atherosclerosis . . . . . . . . . 1 B. Vessel Structure . . . . . . . . . . . . . . . . . . . . . . . 6 1. Arterial wall . . . . . . . . . . . . . . . . . . . . . . . 6 2. Blood and its constituents... . . . . . . . . . . . . . . . . 7 C. Process of Plaque Formation . . . . . . . . . . . . . . . . . 8 1. Localization of atherosclerotic plaque . . . . . . . . . 8 2. Stages of atherosclerosis . . . . . . . . . . . . . . . . . 9 3. Inflammation by macrophages...

  3. Thermal study of vulnerable atherosclerotic plaque 

    E-print Network

    Kim, Taehong

    2009-05-15

    ranged from 0.1 to 0.25 oC in the plaque/lumen interface. In 3-D realistic model, the multiple measuring points must be considered to decrease the potential error in temperature measurement even within 1 or 2 mm at centerline region of plaque. The most...

  4. Purine catabolism in advanced carotid artery plaque.

    PubMed

    Felici, C; Ciari, I; Terzuoli, L; Porcelli, B; Setacci, C; Giubbolini, M; Marinello, E

    2006-01-01

    This study was carried out on carotid artery plaque and plasma of 50 patients. We analyzed uric acid, hypoxanthine, xanthine, and allantoin levels to verify if enzymatic purine degradation occurs in advanced carotid plaque; we also determined free radicals and sulphydryl groups to check if there is a correlation between oxidant status and purine catabolism. Comparing plaque and plasma we found higher levels of free radicals, hypoxanthine, xanthine, and a decrease of some oxidant protectors, such as sulphydryl groups and uric acid, in plaque. We also observed a very important phenomenon in plaque, the presence of allantoin due to chemical oxidation of uric acid, since humans do not have the enzyme uricase. The hypothetical elevated activity of xanthine oxidase in atherosclerosis could be reduced by specific therapies using its inhibitors, such as oxypurinol or allopurinol. PMID:17065109

  5. Advanced Techniques for MRI of Atherosclerotic Plaque

    PubMed Central

    Kerwin, William S.; Canton, Gador

    2011-01-01

    This review examines the state of the art in vessel wall imaging by MRI with an emphasis on the biomechanical assessment of atherosclerotic plaque. Three areas of advanced techniques are discussed. First, alternative contrast mechanisms, including susceptibility, magnetization transfer, diffusion and perfusion, are presented in regards to how they facilitate accurate determination of plaque constituents underlying biomechanics. Second, imaging technologies, including hardware and sequences, are reviewed in regards to how they provide the resolution and SNR necessary for determining plaque structure. Finally, techniques for combining MRI data into an overall assessment of plaque biomechanical properties, including wall shear stress and internal plaque strain, are presented. The paper closes with a discussion of the extent to which these techniques have been applied to different arteries commonly targeted by vessel wall MRI. PMID:20805732

  6. Fibrillar amyloid plaque formation precedes microglial activation.

    PubMed

    Jung, Christian K E; Keppler, Kevin; Steinbach, Sonja; Blazquez-Llorca, Lidia; Herms, Jochen

    2015-01-01

    In Alzheimer's disease (AD), hallmark ?-amyloid deposits are characterized by the presence of activated microglia around them. Despite an extensive characterization of the relation of amyloid plaques with microglia, little is known about the initiation of this interaction. In this study, the detailed investigation of very small plaques in brain slices in AD transgenic mice of the line APP-PS1(dE9) revealed different levels of microglia recruitment. Analysing plaques with a diameter of up to 10 ?m we find that only the half are associated with clear morphologically activated microglia. Utilizing in vivo imaging of new appearing amyloid plaques in double-transgenic APP-PS1(dE9)xCX3CR1+/- mice further characterized the dynamic of morphological microglia activation. We observed no correlation of morphological microglia activation and plaque volume or plaque lifetime. Taken together, our results demonstrate a very prominent variation in size as well as in lifetime of new plaques relative to the state of microglia reaction. These observations might question the existing view that amyloid deposits by themselves are sufficient to attract and activate microglia in vivo. PMID:25799372

  7. Vascular MR segmentation: wall and plaque

    NASA Astrophysics Data System (ADS)

    Yang, Fuxing; Holzapfel, Gerhard; Schulze-Bauer, Christian; Stollberger, Rudolf; Thedens, Daniel; Bolinger, Lizann; Stolpen, Alan; Sonka, Milan

    2003-05-01

    Cardiovascular events frequently result from local rupture of vulnerable atherosclerotic plaque. Non-invasive assessment of plaque vulnerability is needed to allow institution of preventive measures before heart attack or stroke occur. A computerized method for segmentation of arterial wall layers and plaque from high-resolution volumetric MR images is reported. The method uses dynamic programming to detect optimal borders in each MRI frame. The accuracy of the results was tested in 62 T1-weighted MR images from 6 vessel specimens in comparison to borders manually determined by an expert observer. The mean signed border positioning errors for the lumen, internal elastic lamina, and external elastic lamina borders were -0.12+/-0.14 mm, 0.04+/-0.12mm, and -0.15+/-0.13 mm, respectively. The presented wall layer segmentation approach is one of the first steps towards non-invasive assessment of plaque vulnerability in atherosclerotic subjects.

  8. Historical Plaque at Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This plaque, displayed on the grounds of Marshall Space Flight Center in Huntsville, Alabama, commemorates the Redstone Test Stand as an Alabama Historic Civil Engineering Landmark. The site was desinated as such in 1979.

  9. A new inexpensive customized plaque for choroidal melanoma iodine-125 plaque therapy

    SciTech Connect

    Vine, A.K.; Tenhaken, R.K.; Diaz, R.F.; Maxson, B.B.; Lichter, A.S.

    1989-04-01

    The authors have developed a new inexpensive precious metal alloy plaque for use in customized iodine-125 plaque therapy. Each plaque is formed from two flat circular gold/palladium foils which are used in dental crown work. Using a simple manual mechanism, the two forms are stamped over a customized acrylic die shaped to the dimensions of the tumor base plus a 2-mm margin. Completed plaques consist of a back wall, a 2-mm side wall, and a 1.5-mm wide lip with holes for suture placement. Advantages include: simple construction from inexpensive components, customized shape, and iodine seeds that are readily visible on plane radiographs.

  10. Stevia and sucrose effect on plaque formation

    Microsoft Academic Search

    Sonia Maria Blauth de Slavutzky

    2010-01-01

    An in vivo study was done by measuring the accumulation of dental plaque after rinsing with a solution of 10% sucrose four times daily\\u000a during 5 days and comparing it with a rinsing of 10% solution of Stevia rebaudiana Bertoni four times a day, during 5 days a week. The accumulation of dental plaque after rinsing with Stevia was 57, 82% less

  11. Detection of High-Risk Atherosclerotic Plaque

    PubMed Central

    Fleg, Jerome L.; Stone, Gregg W.; Fayad, Zahi A.; Granada, Juan F.; Hatsukami, Thomas S.; Kolodgie, Frank D.; Ohayon, Jacques; Pettigrew, Roderic; Sabatine, Marc S.; Tearney, Guillermo; Waxman, Sergio; Domanski, Michael J.; Srinivas, Pothur R.; Narula, Jagat

    2013-01-01

    The leading cause of major morbidity and mortality in most countries around the world is atherosclerotic cardiovascular disease, most commonly caused by thrombotic occlusion of a high-risk coronary plaque resulting in myocardial infarction or cardiac death, or embolization from a high-risk carotid plaque resulting in stroke. The lesions prone to result in such clinical events are termed vulnerable or high-risk plaques, and their identification may lead to the development of pharmacological and mechanical intervention strategies to prevent such events. Autopsy studies from patients dying of acute myocardial infarction or sudden death have shown that such events typically arise from specific types of atherosclerotic plaques, most commonly the thin-cap fibroatheroma. However, the search in human beings for vulnerable plaques before their becoming symptomatic has been elusive. Recently, the PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree) study demonstrated that coronary plaques that are likely to cause future cardiac events, regardless of angiographic severity, are characterized by large plaque burden and small lumen area and/or are thin-cap fibroatheromas verified by radiofrequency intravascular ultrasound imaging. This study opened the door to identifying additional invasive and noninvasive imaging modalities that may improve detection of high-risk atherosclerotic lesions and patients. Beyond classic risk factors, novel biomarkers and genetic profiling may identify those patients in whom noninvasive imaging for vulnerable plaque screening, followed by invasive imaging for risk confirmation is warranted, and in whom future pharmacological and/or device-based focal or regional therapies may be applied to improve long-term prognosis. PMID:22974808

  12. Penetration of fluoride into natural plaque biofilms.

    PubMed

    Watson, P S; Pontefract, H A; Devine, D A; Shore, R C; Nattress, B R; Kirkham, J; Robinson, C

    2005-05-01

    Caries occurs at inaccessible stagnation sites where plaque removal is difficult. Here, the penetration through plaque of protective components, such as fluoride, is likely to be crucial in caries inhibition. We hypothesized that topically applied fluoride would readily penetrate such plaque deposits. In this study, plaque biofilms generated in vivo on natural enamel surfaces were exposed to NaF (1000 ppm F-) for 30 or 120 sec (equivalent to toothbrushing) or for 30 min. Biofilms were then sectioned throughout their depth, and the fluoride content of each section was determined with the use of a fluoride electrode. Exposure to NaF for 30 or 120 sec increased plaque fluoride concentrations near the saliva interface, while concentrations near the enamel surface remained low. Fluoride penetration increased with duration of NaF exposure. Removal of exogenous fluoride resulted in fluoride loss and redistribution. Penetration of fluoride into plaque biofilms during brief topical exposure is restricted, which may limit anti-caries efficacy. PMID:15840782

  13. PLAQUE:PLAQUE: What it is and how to get rid of it

    E-print Network

    Bandettini, Peter A.

    . Red, puffy or bleeding gums can be the first signs of gum disease. If gum disease is not treated for keeping your teeth and gums ­healthy plus seeing your dentist regularly--you can have your teeth and stick to the teeth. · Some types of plaque cause tooth decay. · Other types of plaque cause gum disease

  14. AdipositasErhöhte Mortalität durch arteriosklerotische Folgekrankheiten und Karzinome

    Microsoft Academic Search

    A. Wirth

    1997-01-01

    Zum Thema  \\u000a „La?t wohlbeleibte M?nner um mich sein …” so ?bersetzt A.W. Schlegel die Worte Caesars in Shakespeares Julius Caesar (1, 2).\\u000a Der Dichter hatte sich noch eindeutiger ausgedr?ckt: „let me have men about me that are fat …” Wenn auch nach unserem Sprachgef?hl\\u000a hier ein Unterschied ist, der Begriff „wohlbeleibt” oder „fat” ist sicher eher positiv als negativ besetzt.

  15. Simulation of human atherosclerotic femoral plaque tissue: the influence of plaque material model on numerical results

    PubMed Central

    2015-01-01

    Background Due to the limited number of experimental studies that mechanically characterise human atherosclerotic plaque tissue from the femoral arteries, a recent trend has emerged in current literature whereby one set of material data based on aortic plaque tissue is employed to numerically represent diseased femoral artery tissue. This study aims to generate novel vessel-appropriate material models for femoral plaque tissue and assess the influence of using material models based on experimental data generated from aortic plaque testing to represent diseased femoral arterial tissue. Methods Novel material models based on experimental data generated from testing of atherosclerotic femoral artery tissue are developed and a computational analysis of the revascularisation of a quarter model idealised diseased femoral artery from a 90% diameter stenosis to a 10% diameter stenosis is performed using these novel material models. The simulation is also performed using material models based on experimental data obtained from aortic plaque testing in order to examine the effect of employing vessel appropriate material models versus those currently employed in literature to represent femoral plaque tissue. Results Simulations that employ material models based on atherosclerotic aortic tissue exhibit much higher maximum principal stresses within the plaque than simulations that employ material models based on atherosclerotic femoral tissue. Specifically, employing a material model based on calcified aortic tissue, instead of one based on heavily calcified femoral tissue, to represent diseased femoral arterial vessels results in a 487 fold increase in maximum principal stress within the plaque at a depth of 0.8 mm from the lumen. Conclusions Large differences are induced on numerical results as a consequence of employing material models based on aortic plaque, in place of material models based on femoral plaque, to represent a diseased femoral vessel. Due to these large discrepancies, future studies should seek to employ vessel-appropriate material models to simulate the response of diseased femoral tissue in order to obtain the most accurate numerical results. PMID:25602515

  16. Hyperspectral imaging of atherosclerotic plaques in vitro

    NASA Astrophysics Data System (ADS)

    Larsen, Eivind L. P.; Randeberg, Lise L.; Olstad, Elisabeth; Haugen, Olav A.; Aksnes, Astrid; Svaasand, Lars O.

    2011-02-01

    Vulnerable plaques constitute a risk for serious heart problems, and are difficult to identify using existing methods. Hyperspectral imaging combines spectral- and spatial information, providing new possibilities for precise optical characterization of atherosclerotic lesions. Hyperspectral data were collected from excised aorta samples (n = 11) using both white-light and ultraviolet illumination. Single lesions (n = 42) were chosen for further investigation, and classified according to histological findings. The corresponding hyperspectral images were characterized using statistical image analysis tools (minimum noise fraction, K-means clustering, principal component analysis) and evaluation of reflectance/fluorescence spectra. Image analysis combined with histology revealed the complexity and heterogeneity of aortic plaques. Plaque features such as lipids and calcifications could be identified from the hyperspectral images. Most of the advanced lesions had a central region surrounded by an outer rim or shoulder-region of the plaque, which is considered a weak spot in vulnerable lesions. These features could be identified in both the white-light and fluorescence data. Hyperspectral imaging was shown to be a promising tool for detection and characterization of advanced atherosclerotic plaques in vitro. Hyperspectral imaging provides more diagnostic information about the heterogeneity of the lesions than conventional single point spectroscopic measurements.

  17. Effect of gum chewing on plaque accumulation.

    PubMed

    Hoerman, K C; Gasior, E J; Zibell, S E; Record, D; Flowerdew, G

    1990-01-01

    The purpose of this investigation was to test the effect of chewing gum sweetened with either sorbitol (LG) or sucrose (SG) on the growth of plaque on tooth enamel surfaces. Nineteen dental students, in a balanced crossover design, chewed the two gums for 5 days without normal oral hygiene practices. The control treatment was a 5-day non-chewing (NG) phase. A period of 9 days was allowed for normal hygiene between test phases. The chewing regimen required 20 minutes of use of one stick of chewing gum immediately after meals or snacks. The average number of sticks chewed was 3.8/day. Pre- and post-treatment plaque scores were recorded by two examiners using a Modified Navy Plaque Index (PLI) from 0 to 9 along each of four surfaces to assess six Ramfjord teeth. Pre-treatment mean PLI scores for the 3 test treatments were, NG = 2.0, LG = 1.9 and SG = 1.9. Post-treatment mean PLI scores were, NG = 3.6, LG = 3.3 and SG = 3.3. ANOVA of pre- and post-treatment scores revealed no significant differences between treatments. Post-treatment scores of the 2 chewing gums were then pooled, independent of sweetener. ANOVA of these data revealed chewing gum (LG + SG = 3.3) to cause significantly less plaque accumulation than no gum (NG = 3.6). In a no oral hygiene environment, plaque accumulation during use of sorbitol chewing gum or sucrose chewing gum was statistically the same. However, chewing gum, irrespective of sweetener, caused significantly less plaque accumulation than no chewing. PMID:2133390

  18. Assessment of vulnerable plaque composition by matching the deformation of a parametric plaque model to measured plaque deformation

    Microsoft Academic Search

    Radj A. Baldewsing; Johannes A. Schaar; Frits Mastik; Cees. W. J. Oomens; Antonius F. W. van der Steen

    2005-01-01

    Intravascular ultrasound (IVUS) elastography visualizes local radial strain of arteries in so-called elastograms to detect rupture-prone plaques. However, due to the unknown arterial stress distribution these elastograms cannot be directly interpreted as a morphology and material composition image. To overcome this limitation we have developed a method that reconstructs a Young's modulus image from an elastogram. This method is especially

  19. 18. Photocopy of drawing of bronze dedication plaque, circa 1903 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Photocopy of drawing of bronze dedication plaque, circa 1903 (original drawing in possession of City Engineer's Office Grand Rapids, Michigan) DEDICATION PLAQUE. - Bridge Street Bridge, Spanning Grand River, Michigan & Bridge Streets, Grand Rapids, Kent County, MI

  20. Estimation of nonlinear mechanical properties of atherosclerotic plaques

    E-print Network

    Zhu, Ting F. (Ting Fredrick)

    2005-01-01

    A numerical method has been developed to estimate the mechanical properties of atherosclerotic plaques by combining genetic algorithm with finite element methods. Plaque images derived from optical coherence tomography ...

  1. Coronary CT Angiography in the Quantitative Assessment of Coronary Plaques

    PubMed Central

    2014-01-01

    Coronary computed tomography angiography (CCTA) has been recently evaluated for its ability to assess coronary plaque characteristics, including plaque composition. Identification of the relationship between plaque composition by CCTA and patient clinical presentations may provide insight into the pathophysiology of coronary artery plaque, thus assisting identification of vulnerable plaques which are associated with the development of acute coronary syndrome. CCTA-generated 3D visualizations allow evaluation of both coronary lesions and lumen changes, which are considered to enhance the diagnostic performance of CCTA. The purpose of this review is to discuss the recent developments that have occurred in the field of CCTA with regard to its diagnostic accuracy in the quantitative assessment of coronary plaques, with a focus on the characterization of plaque components and identification of vulnerable plaques. PMID:25162010

  2. Microanalysis of Senile Plaques Using Nuclear Microscopy

    Microsoft Academic Search

    Judith Landsberg; Brendan McDonald; Geoff Grime; Frank Watt

    1993-01-01

    Silver-staining “senile” plaques occurring in the brain are a major part of the pathology of Alzheimer's disease. The elemental composition of these structures, and the possible presence of aluminum and silicon in these structures, has been the subject of an increasing research effort over the last decade. However, the results have often been contradictory.Using a scanning proton microprobe, the elemental

  3. Biomechanics of Plaque Rupture: Progress, Problems, and New Frontiers

    Microsoft Academic Search

    Peter D. Richardson

    2002-01-01

    Plaque rupture has become identified as a critical step in the evolution of arterial plaques, especially as clinically significant events occur in critical arteries. It has become common in the past dozen years or so to consider which plaques are vulnerable, even though not yet ruptured. Thrombotic events have remained significant, but in a context where they are seen as

  4. In vivo imaging reveals sigmoidal growth kinetic of ?-amyloid plaques

    PubMed Central

    2014-01-01

    A major neuropathological hallmark of Alzheimer’s disease is the deposition of amyloid plaques in the brains of affected individuals. Amyloid plaques mainly consist of fibrillar ?-amyloid, which is a cleavage product of the amyloid precursor protein. The amyloid-cascade-hypothesis postulates A? accumulation as the central event in initiating a toxic cascade leading to Alzheimer’s disease pathology and, ultimately, loss of cognitive function. We studied the kinetics of ?-amyloid deposition in Tg2576 mice, which overexpress human amyloid precursor protein with the Swedish mutation. Utilizing long-term two-photon imaging we were able to observe the entire kinetics of plaque growth in vivo. Essentially, we observed that plaque growth follows a sigmoid-shaped curve comprising a cubic growth phase, followed by saturation. In contrast, plaque density kinetics exhibited an asymptotic progression. Taking into account the fact that a critical concentration of A? is required to seed new plaques, we can propose the following kinetic model of ?-amyloid deposition in vivo. In the early cubic phase, plaque growth is not limited by A? concentration and plaque density increases very fast. During the transition phase, plaque density stabilizes whereas plaque volume increases strongly reflecting a robust growth of the plaques. In the late asymptotic phase, A? peptide production becomes rate-limiting for plaque growth. In conclusion, the present study offers a direct link between in vitro and in vivo studies facilitating the translation of A?-lowering strategies from laboratory models to patients. PMID:24678659

  5. Quantifying Effects of Plaque Structure and Material Properties on Stress Distributions in Human Atherosclerotic Plaques Using 3D FSI Models

    PubMed Central

    Tang, Dalin; Yang, Chun; Zheng, Jie; Woodard, Pamela K.; Saffitz, Jeffrey E.; Sicard, Gregorio A.; Pilgram, Thomas K.; Yuan, Chun

    2006-01-01

    Background Atherosclerotic plaques may rupture without warning and cause acute cardiovascular syndromes such as heart attack and stroke. Methods to assess plaque vulnerability noninvasively and predict possible plaque rupture are urgently needed. Method MRI-based three-dimensional unsteady models for human atherosclerotic plaques with multi-component plaque structure and fluid-structure interactions are introduced to perform mechanical analysis for human atherosclerotic plaques. Results Stress variations on critical sites such as a thin cap in the plaque can be 300% higher than that at other normal sites. Large calcification block considerably changes stress/strain distributions. Stiffness variations of plaque components (50% reduction or 100% increase) may affect maximal stress values by 20–50 %. Plaque cap erosion causes almost no change on maximal stress level at the cap, but leads to 50% increase in maximal strain value. Conclusions Effects caused by atherosclerotic plaque structure, cap thickness and erosion, material properties, and pulsating pressure conditions on stress/strain distributions in the plaque are quantified by extensive computational case studies and parameter evaluations. Computational mechanical analysis has good potential to improve accuracy of plaque vulnerability assessment. PMID:16502661

  6. Imaging of coronary atherosclerosis and identification of the vulnerable plaque

    PubMed Central

    de Feyter, P.J.; Serruys, P. W.; Nieman, K.; Mollet, N.; Cademartiri, F.; van Geuns, R. J.; Slager, C.; van der Steen, A.F.W.; Krams, R.; Schaar, J.A.; Wielopolski, P.; Pattynama, P.M.T.; Arampatzis, A.; van der Lugt, A.; Regar, E.; Ligthart, J.; Smits, P.

    2003-01-01

    Identification of the vulnerable plaque responsible for the occurrence of acute coronary syndromes and acute coronary death is a prerequisite for the stabilisation of this vulnerable plaque. Comprehensive coronary atherosclerosis imaging in clinical practice should involve visualisation of the entire coronary artery tree and characterisation of the plaque, including the three-dimensional morphology of the plaque, encroachment of the plaque on the vessel lumen, the major tissue components of the plaque, remodelling of the vessel and presence of inflammation. Obviously, no single diagnostic modality is available that provides such comprehensive imaging and unfortunately no diagnostic tool is available that unequivocally identifies the vulnerable plaque. The objective of this article is to discuss experience with currently available diagnostic modalities for coronary atherosclerosis imaging. In addition, a number of evolving techniques will be briefly discussed. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:25696244

  7. The generalized geometry of eye plaque therapy.

    PubMed

    Kepka, A G; Johnson, P M; Kline, R W

    1988-01-01

    A calculation is described that enables the rapid assessment of dose rate at various points of interest within the eye (lens, optic nerve, etc.) for the treatment of choroidal melanoma by plaque therapy. 125I seeds are used as the radiation source. The location of the plaque and its associated seeds relative to the eye (in a Cartesian coordinate system) is determined from the description of the tumor, as drawn and dimensioned on a fundus-view diagram by the ophthalmologist. This requires a computer to numerically solve an equation, which is derived in the framework of spherical geometry. Further results of this calculation yield data files that serve as the input to a conventional brachytherapy treatment planning program. This enables the visualization of the dose distribution within a plane that contains the major axis of the tumor in order to assess the adequacy of the treated volume. PMID:3405140

  8. Plaque formation of dietary isomaltulose in humans.

    PubMed

    Ooshima, T; Izumitani, A; Takei, T; Fujiwara, T; Sobue, S

    1990-01-01

    The plaque formation of isomaltulose, a sucrose isomer, was examined in 15 human volunteers with both diet and oral hygiene under supervision. The subjects were requested to refrain from all oral hygiene procedures for 3 days and were provided between-meal snacks containing 157 g of 4 test sugars (100% isomaltulose, 70% isomaltulose + 30% sucrose, 50% isomaltulose + 50% sucrose, and 100% sucrose). The study was repeated 4 times over 4 weeks. The isomaltulose diet resulted in the lowest plaque index, while sucrose induced a significantly greater deposition. In the absence of sucrose-containing snacks, mutans streptococci in saliva decreased below the baseline level. These results suggest that isomaltulose may be a suitable substitute for sucrose in between meal snacks. PMID:2293892

  9. Enucleation versus plaque irradiation for choroidal melanoma

    SciTech Connect

    Straatsma, B.R.; Fine, S.L.; Earle, J.D.; Hawkins, B.S.; Diener-West, M.; McLaughlin, J.A.

    1988-07-01

    The Collaborative Ocular Melanoma Study (COMS) is an international, multicenter-controlled study. The organization includes an Executive Committee, Steering Committee, 6 Central Units, 32 Clinical Centers, and a Data and Safety Monitoring Committee. Scientifically, the COMS consists of (1) a randomized trial of patients with medium choroidal melanoma treated with enucleation versus iodine-125 plaque irradiation, (2) a randomized trial of patients with large choroidal melanoma treated with enucleation versus preenucleation external beam irradiation and enucleation, and (3) a prospective observational study of patients with small choroidal melanoma to determine whether a randomized trial of treatment is appropriate. In design and conduct of the COMS, special consideration is given to biostatistics and sample size considerations, iodine-125 plaque irradiation of choroidal melanoma, and coordinated ocular melanoma research. Recruitment is in progress. However, the pool of eligible patients is limited and the COMS needs the continued support and cooperation of ophthalmologists throughout the United States and Canada.

  10. Thrombogenic potential of human coronary atherosclerotic plaques

    Microsoft Academic Search

    Raffaela Fetiveau; Stefano Lucreziotti; Robert D. Rosenberg; Pier Mannuccio; Mannucci Diego Ardissino; Piera Angelica Merlini; Kenneth A. Bauer; Ezio Bramucci; Maurizio Ferrario; Pier Mannuccio Mannucci

    2001-01-01

    the procedure, plasma prothrombin frag- ment 1 1 2 levels were significantly in- creased across the lesion in patients with unstable, but not in those with stable, coronary disease (unstable, median in- crease, 0.37 nM; range, 20.35-1.16 nM) (stable, median increase, 20.065 nM; range, 20.58-1.06 nM) (P 5 .0021). After plaque removal, an increase in prothrom- bin fragment 1 1

  11. Microwave plaque thermoradiotherapy for choroidal melanoma.

    PubMed Central

    Finger, P. T.

    1992-01-01

    Microwave thermoradiotherapy was used as a primary treatment for 44 patients with choroidal melanoma. An episcleral dish-shaped microwave antenna was placed beneath the tumour at the time of plaque brachytherapy. While temperatures were measured at the sclera, the tumour's apex was targeted to receive a minimum of 42 degrees C for 45 minutes. In addition, the patients received full or reduced doses of plaque radiotherapy. No patients have been lost to follow-up. Two eyes have been enucleated: one for rubeotic glaucoma, and one for uveitic glaucoma. Though six patients have died, only one death was due to metastatic choroidal melanoma (39 months after treatment). Clinical observations suggest that the addition of microwave heating to plaque radiation therapy of choroidal melanoma has been well tolerated. There has been a 97.7% local control rate (with a mean follow-up of 22.2 months). We have reduced the minimum tumour radiation dose (apex dose) to levels used for thermoradiotherapy of cutaneous melanomas (50 Gy/5000 rad). Within the range of this follow-up period no adverse effects which might preclude the use of this microwave heat delivery system for treatment of choroidal melanoma have been noted. Images PMID:1622949

  12. Ghrelin receptor deficiency aggravates atherosclerotic plaque instability and vascular inflammation.

    PubMed

    Zhang, Min; Qu, Xinkai; Yuan, Fang; Yang, Yiqing; Xu, Lei; Dai, Jinjie; Wang, Weigang; Fei, Jian; Hou, Xumin; Fang, Weiyi

    2015-01-01

    Ghrelin has been found to be associated with anti-inflammatory effects, inhibition of atherosclerotic plaque formation, and plaque stability in the cardiovascular system. We investigated whether ghrelin affected atherosclerotic plaque and inflammation found in atherosclerosis. We crossed ghrelin receptor knock out mice (growth hormone secretagogue receptor (GHSR)-/-) and low-density lipoprotein receptor-null (low-density lipoprotein receptor (LDLR)-/-) mice. In this model, atherosclerotic lesions were promoted by administering a high-fat, high-cholesterol, Western-type diet for 18 weeks. Serum lipid levels, atherosclerotic plaque on the aortic arches, and expression of intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), T cells, macrophages, and smooth muscle cells of atherosclerotic plaque were observed. Although serum lipid levels and atherosclerotic plaque in aortic arches were not significantly different between GHSR+/+/LDLR-/- and GHSR -/-LDLR-/- mice, ICAM-1 and VCAM-1 protein expression in atherosclerotic plaques were increased in GHSR -/-LDLR-/- mice compared with GHSR+/+/LDLR-/- mice. T cells and macrophages were increased, while smooth muscle cells of atherosclerotic plaques were less in GHSR -/-LDLR-/- mice than that in GHSR+/+/LDLR-/- mice. In conclusion, ghrelin receptor deficiency aggravates atherosclerotic plaque instability and vascular inflammation but not the surface area of atherosclerotic plaque. This information will provide novel avenues for the treatment of patients with atherosclerosis.  PMID:25553467

  13. Intravascular probe for detection of vulnerable plaque

    NASA Astrophysics Data System (ADS)

    Patt, Bradley E.; Iwanczyk, Jan S.; MacDonald, Lawrence R.; Yamaguchi, Yuko; Tull, Carolyn R.; Janecek, Martin; Hoffman, Edward J.; Strauss, H. William; Tsugita, Ross; Ghazarossian, Vartan

    2001-12-01

    Coronary angiography is unable to define the status of the atheroma, and only measures the luminal dimensions of the blood vessel, without providing information about plaque content. Up to 70% of heart attacks are caused by minimally obstructive vulnerable plaques, which are too small to be detected adequately by angiography. We have developed an intravascular imaging detector to identify vulnerable coronary artery plaques. The detector works by sensing beta or conversion electron radiotracer emissions from plaque-binding radiotracers. The device overcomes the technical constraints of size, sensitivity and conformance to the intravascular environment. The detector at the distal end of the catheter uses six 7mm long by 0.5mm diameter scintillation fibers coupled to 1.5m long plastic fibers. The fibers are offset from each other longitudinally by 6mm and arranged spirally around a guide wire in the catheter. At the proximal end of the catheter the optical fibers are coupled to an interface box with a snap on connector. The interface box contains a position sensitive photomultiplier tube (PSPMT) to decode the individual fibers. The whole detector assembly fits into an 8-French (2.7 mm in diameter) catheter. The PSPMT image is further decoded with software to give a linear image, the total instantaneous count rate and an audio output whose tone corresponds to the count rate. The device was tested with F-18 and Tl-204 sources. Spectrometric response, spatial resolution, sensitivity and beta to background ratio were measured. System resolution is 6 mm and the sensitivity is >500 cps / micrometers Ci when the source is 1 mm from the detector. The beta to background ratio was 11.2 for F-18 measured on a single fiber. The current device will lead to a system allowing imaging of labeled vulnerable plaque in coronary arteries. This type of signature is expected to enable targeted and cost effective therapies to prevent acute coronary artery diseases such as: unstable angina, acute myocardial infarction, and sudden cardiac death.

  14. Bacterial Diversity in Human Subgingival Plaque

    PubMed Central

    Paster, Bruce J.; Boches, Susan K.; Galvin, Jamie L.; Ericson, Rebecca E.; Lau, Carol N.; Levanos, Valerie A.; Sahasrabudhe, Ashish; Dewhirst, Floyd E.

    2001-01-01

    The purpose of this study was to determine the bacterial diversity in the human subgingival plaque by using culture-independent molecular methods as part of an ongoing effort to obtain full 16S rRNA sequences for all cultivable and not-yet-cultivated species of human oral bacteria. Subgingival plaque was analyzed from healthy subjects and subjects with refractory periodontitis, adult periodontitis, human immunodeficiency virus periodontitis, and acute necrotizing ulcerative gingivitis. 16S ribosomal DNA (rDNA) bacterial genes from DNA isolated from subgingival plaque samples were PCR amplified with all-bacterial or selective primers and cloned into Escherichia coli. The sequences of cloned 16S rDNA inserts were used to determine species identity or closest relatives by comparison with sequences of known species. A total of 2,522 clones were analyzed. Nearly complete sequences of approximately 1,500 bases were obtained for putative new species. About 60% of the clones fell into 132 known species, 70 of which were identified from multiple subjects. About 40% of the clones were novel phylotypes. Of the 215 novel phylotypes, 75 were identified from multiple subjects. Known putative periodontal pathogens such as Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola were identified from multiple subjects, but typically as a minor component of the plaque as seen in cultivable studies. Several phylotypes fell into two recently described phyla previously associated with extreme natural environments, for which there are no cultivable species. A number of species or phylotypes were found only in subjects with disease, and a few were found only in healthy subjects. The organisms identified only from diseased sites deserve further study as potential pathogens. Based on the sequence data in this study, the predominant subgingival microbial community consisted of 347 species or phylotypes that fall into 9 bacterial phyla. Based on the 347 species seen in our sample of 2,522 clones, we estimate that there are 68 additional unseen species, for a total estimate of 415 species in the subgingival plaque. When organisms found on other oral surfaces such as the cheek, tongue, and teeth are added to this number, the best estimate of the total species diversity in the oral cavity is approximately 500 species, as previously proposed. PMID:11371542

  15. Growth of Microorganisms from Supragingival Dental Plaque on Saliva Agar

    Microsoft Academic Search

    M. H. De Jong; J. S. Van Der Hoeven; J. H. Van Os

    1986-01-01

    The role of saliva in supporting the growth of dental plaque has scarcely been investigated. We have studied the growth and recovery of micro-organisms from dental plaque samples on saliva-agar plates, prepared from filter-sterilized wax-stimulated whole saliva. Under optimal conditions, the mean recovery of plaque samples on saliva agar was about 50% (range, 22-77) of the recovery on blood agar.

  16. Stability Analysis of a Model of Atherosclerotic Plaque Growth

    PubMed Central

    Reddy, Sushruth; Seshaiyer, Padmanabhan

    2015-01-01

    Atherosclerosis, the formation of life-threatening plaques in blood vessels, is a form of cardiovascular disease. In this paper, we analyze a simplified model of plaque growth to derive physically meaningful results about the growth of plaques. In particular, the main results of this paper are two conditions, which express that the immune response increases as LDL cholesterol levels increase and that diffusion prevails over inflammation in a healthy artery. PMID:25883675

  17. A Plaque Assay for the Simian Rotavirus SA11

    Microsoft Academic Search

    ERIC M. SMITH; MARY KOLB ESTES; DAVID Y. GRAHAM; CHARLES P. GERBA

    1979-01-01

    SUMMARY A sensitive, quantitative and reproducible plaque assay for the measurement of the simian rotavirus SAII is described. Plaque formation required the presence of the facilitators pancreatin or trypsin and diethylaminoethyl-dextran in the agar overlay. SAII produced plaques in three continuous primate cell lines: MA-Io4, CV-I and LLC-MK2. MA-Io 4 cells were the most sensitive.

  18. Multimodal spectroscopy detects features of vulnerable atherosclerotic plaque

    E-print Network

    Scepanovic, Obrad R.

    Early detection and treatment of rupture-prone vulnerable atherosclerotic plaques is critical to reducing patient mortality associated with cardiovascular disease. The combination of reflectance, fluorescence, and Raman ...

  19. Dural metastasis masquerading as an en plaque meningioma

    PubMed Central

    Kapoor, Ankur; Savardekar, Amey; Chaterjee, Debajyaoti; Salunke, Pravin; Vasishta, Rakesh K; Bhattacharya, Anish

    2015-01-01

    Metastatic adenocarcinoma mimicking meningioma is rare; and any metastatic lesion masquerading as an en plaque meningioma is extremely rare. We report the case of a 50-year-old female, who presented with headache and left hemiparesis for 1 month and on imaging showed a dural-based enhancing mass along the right hemisphere. The patient was operated with a working diagnosis of en plaque meningioma. Histopathology revealed metastatic adenocarcinoma. This report highlights an unusual radiological presentation of a metastatic lesion as dural based en plaque variety. Metastasis should be borne in mind for any en plaque lesion with rapid clinical progression. PMID:26167033

  20. Expression of NPP1 is regulated during atheromatous plaque calcification

    PubMed Central

    Nitschke, Yvonne; Hartmann, Simone; Torsello, Giovanni; Horstmann, Rüdiger; Seifarth, Harald; Weissen-Plenz, Gabriele; Rutsch, Frank

    2011-01-01

    Abstract Mutations of the ENPP1 gene encoding ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) are associated with medial calcification in infancy. While the inhibitory role of matrix proteins such as osteopontin (OPN) with respect to atherosclerotic plaque calcification has been established, the role of NPP1 in plaque calcification is not known. We assessed the degree of plaque calcification (computed tomography), NPP1 and OPN localization (immunohistochemistry) and expression (RT-PCR) in a cohort of 45 patients undergoing carotid endatherectomy for significant stenosis of the internal carotid artery and in normal arteries (N= 50). We correlated NPP1 and OPN expression levels to the degree of plaque calcification, to pro-atherogenic factors and statin therapy. NPP1 was demonstrated in the base and in the shoulder of atherosclerotic plaques. Compared to normal arteries and non-calcified plaques, in calcified plaques NPP1 mRNA was decreased (P < 0.0001). OPN mRNA levels were up-regulated in carotid atheroma. NPP1 and OPN expression levels positively correlated with the degree of plaque calcification (R= 0.54, P= 0.00019 and R= 0.46, P= 0.017, respectively) and with risk factors of atherosclerosis. Expression of the calcification inhibitor NPP1 is down-regulated in calcified atherosclerotic plaques. Our correlation data point to a counter-active mechanism, which in the end turns out to be insufficient to prevent further progression of calcification. PMID:20015201

  1. Subsurface ablation of atherosclerotic plaque using ultrafast laser pulses

    PubMed Central

    Lanvin, Thomas; Conkey, Donald B.; Frobert, Aurelien; Valentin, Jeremy; Goy, Jean-Jacques; Cook, Stéphane; Giraud, Marie-Noelle; Psaltis, Demetri

    2015-01-01

    We perform subsurface ablation of atherosclerotic plaque using ultrafast pulses. Excised mouse aortas containing atherosclerotic plaque were ablated with ultrafast near-infrared (NIR) laser pulses. Optical coherence tomography (OCT) was used to observe the ablation result, while the physical damage was inspected in histological sections. We characterize the effects of incident pulse energy on surface damage, ablation hole size, and filament propagation. We find that it is possible to ablate plaque just below the surface without causing surface damage, which motivates further investigation of ultrafast ablation for subsurface atherosclerotic plaque removal.

  2. Oral biofilm models for mechanical plaque removal.

    PubMed

    Verkaik, Martinus J; Busscher, Henk J; Rustema-Abbing, Minie; Slomp, Anje M; Abbas, Frank; van der Mei, Henny C

    2010-08-01

    In vitro plaque removal studies require biofilm models that resemble in vivo dental plaque. Here, we compare contact and non-contact removal of single and dual-species biofilms as well as of biofilms grown from human whole saliva in vitro using different biofilm models. Bacteria were adhered to a salivary pellicle for 2 h or grown after adhesion for 16 h, after which, their removal was evaluated. In a contact mode, no differences were observed between the manual, rotating, or sonic brushing; and removal was on average 39%, 84%, and 95% for Streptococcus mutans, Streptococcus oralis, and Actinomyces naeslundii, respectively, and 90% and 54% for the dual- and multi-species biofilms, respectively. However, in a non-contact mode, rotating and sonic brushes still removed considerable numbers of bacteria (24-40%), while the manual brush as a control (5-11%) did not. Single A. naeslundii and dual-species (A. naeslundii and S. oralis) biofilms were more difficult to remove after 16 h growth than after 2 h adhesion (on average, 62% and 93% for 16- and 2-h-old biofilms, respectively), while in contrast, biofilms grown from whole saliva were easier to remove (97% after 16 h and 54% after 2 h of growth). Considering the strong adhesion of dual-species biofilms and their easier more reproducible growth compared with biofilms grown from whole saliva, dual-species biofilms of A. naeslundii and S. oralis are suggested to be preferred for use in mechanical plaque removal studies in vitro. PMID:19565279

  3. Oral biofilm models for mechanical plaque removal

    PubMed Central

    Verkaik, Martinus J.; Busscher, Henk J.; Rustema-Abbing, Minie; Slomp, Anje M.; Abbas, Frank

    2009-01-01

    In vitro plaque removal studies require biofilm models that resemble in vivo dental plaque. Here, we compare contact and non-contact removal of single and dual-species biofilms as well as of biofilms grown from human whole saliva in vitro using different biofilm models. Bacteria were adhered to a salivary pellicle for 2 h or grown after adhesion for 16 h, after which, their removal was evaluated. In a contact mode, no differences were observed between the manual, rotating, or sonic brushing; and removal was on average 39%, 84%, and 95% for Streptococcus mutans, Streptococcus oralis, and Actinomyces naeslundii, respectively, and 90% and 54% for the dual- and multi-species biofilms, respectively. However, in a non-contact mode, rotating and sonic brushes still removed considerable numbers of bacteria (24–40%), while the manual brush as a control (5–11%) did not. Single A. naeslundii and dual-species (A. naeslundii and S. oralis) biofilms were more difficult to remove after 16 h growth than after 2 h adhesion (on average, 62% and 93% for 16- and 2-h-old biofilms, respectively), while in contrast, biofilms grown from whole saliva were easier to remove (97% after 16 h and 54% after 2 h of growth). Considering the strong adhesion of dual-species biofilms and their easier more reproducible growth compared with biofilms grown from whole saliva, dual-species biofilms of A. naeslundii and S. oralis are suggested to be preferred for use in mechanical plaque removal studies in vitro. PMID:19565279

  4. Congenital milia en plaque on scalp.

    PubMed

    Ghosh, Sangita; Sangal, Shikha

    2015-01-01

    Milia en plaque is a rare disease entity characterized by confluence of multiple keratin-filled cysts resulting from the obstruction of hair follicle without any preceding primary dermatosis. Fewer than 40 cases have been reported so far in dermatological literature, and most cases are described to occur in adults and in the peri-auricular area. We describe a case of congenital MEP on scalp of a five-year-old boy with a blaschkoid extension into posterior nuchal area. This case report claims its uniqueness because of the unusual site and congenital presentation. PMID:25657433

  5. Fibrous Pleural Plaques Detected at Autopsy

    PubMed Central

    TÜRKMEN, Nursel; EREN, Bülent; GÜNDO?MU?, Ümit Naci

    2014-01-01

    The reported case was a 84-year-old male, dead after a traffic accident. The death was considered to be suspicious by prosecutor and an autopsy was mandated. In macroscopic autopsy investigation left tibia, fibula and multiple rib fractures, widespread seborrheic keratoses, and hyperpigmented skin lesions were detected. In the left chest cavity blood content and white colored lesions spread on the left parietal pleura and chest surface of the thoracic diaphragm were observed. The histological examination of the pleural lesions revealed fibrotic hyalinized structures with calcified foci. Investigation of pleural plaques in forensic autopsy is important for scientific classification of this interesting entity. PMID:25705312

  6. [Plaque surgery for Peyronie's disease: heterologous grafts].

    PubMed

    Paradiso, Matteo; Sedigh, Omid; Milan, Gian Luca

    2003-06-01

    Surgical treatment of Induratio Penis Plastica includes conservative procedures (phalloplasty), substitutive procedures (prosthesis) and combined procedures (phalloplasty plus prosthesis). Our policy for conservative treatment is based on radical removal of the plaque and replacement with biological patches. During a 15 year experience we employed lyophilized dura mater, autologous dermal graft, preputial skin, cadaveric dermal graft (AlloDerm), venous graft and porcine SIS (Small Intestine Submucosa) graft. Our experience confirms the superiority of venous grafts, but preliminary results with SIS grafts are encouraging. PMID:12868152

  7. Plaque biofilms: the effect of chemical environment on natural human plaque biofilm architecture.

    PubMed

    Robinson, C; Strafford, S; Rees, G; Brookes, S J; Kirkham, J; Shore, R C; Watson, P S; Wood, S

    2006-11-01

    The architecture of microbial biofilms especially the outer regions have an important influence on the interaction between biofilm and local environment particularly on the flux of materials into and out of biofilm compartments and as a consequence, biofilm metabolic behaviour. In the case of dental plaque biofilms, architecture will determine access of nutrients including acidogenic substrates and therapeutic materials to the microbial biomass and to the underlying tooth surface. Manipulation of this architecture may offer a means of altering mass transfer into the whole biofilm and biomass and raises the possibility of improving access of therapeutics. Plaque biofilms formed in vivo on human enamel were subjected to a number of different chemical conditions while under observation by confocal laser scanning microscopy in reflection mode. In this way the outer 50-100 microm or so of the biofilms was examined. Density and distribution of biomass were recorded as degree of reflectance. The amount and density of biofilm biomass increased from the plaque saliva interface towards the interior. Plaque biofilms were robust and little affected by mechanical manipulation, high ionic strength or low pH (2.5). Detergent (SLS), however, often appeared to either remove biomass and/or dramatically reduce its density. PMID:16806048

  8. Correlation between plaque vulnerability of aorta and coronary artery: an evaluation of plaque activity by direct visualization with angioscopy.

    PubMed

    Aono, Jun; Ikeda, Shuntaro; Katsumata, Yuriko; Higashi, Haruhiko; Ohshima, Kousei; Ishibashi, Ken; Matsuoka, Hiroshi; Watanabe, Kouki; Hamada, Mareomi

    2015-08-01

    This study investigated the relationship between the degree of atherosclerotic changes in the descending thoracic aorta (TA) and the coronary artery using angioscopy. Twenty-five consecutive patients undergoing angioscopy of the TA and coronary angiography were enrolled in this study. Participants were divided into three groups according to the angioscopic grading of the TA: white plaque group (W-group), yellow plaque group (Y-group) and intensive yellow, ruptured plaque with ulceration and/or thrombus group (RP-group). The maximum plaque grade, plaque score, number of yellow plaques, frequency of yellow-plaque grades by coronary angioscopy, and SYNTAX score by coronary angiography were evaluated. Brachial-artery pulse wave velocity and high-sensitivity C-reactive protein level tended to be higher in the RP-group than in the other groups, although the differences were not statistically significant. The SYNTAX score was significantly higher in the RP-group than in the W-group (W-group 4.0 ± 3.6 vs. RP-group 17.5 ± 10.0, P = 0.045). In addition, the angioscopic maximum plaque grade, plaque score, and number of yellow plaques in the RP-group were significantly higher than in the W-group (maximum plaque grade W-group 0.8 ± 0.4 vs. RP-group 1.8 ± 0.8, P = 0.026; plaque score W-group 1.0 ± 1.2 vs. RP-group 4.0 ± 1.4, P = 0.014; and number of yellow plaques W-group 1.0 ± 1.2 vs. RP-group 2.5 ± 0.5, P = 0.023). The yellow-plaque grade in the coronary artery was correlated significantly with the plaque grading of TA (P = 0.043). Our study suggests that the angioscopic progression of aortic atherosclerosis is closely associated with vulnerability to and the extent of coronary stenosis, indicating that vulnerability toward atherosclerotic plaque development occurs simultaneously in the coronary tree and systemic arteries. PMID:25916323

  9. Chronic Kidney Disease and Coronary Artery Vulnerable Plaques

    PubMed Central

    Wada, Mitsuru; Higo, Tomoaki; Matsuo, Koshi; Nishio, Mayu; Hirata, Akio; Asai, Mitsutoshi; Nemoto, Takayoshi; Kashiyama, Toshikazu; Murakami, Ayaka; Kashiwase, Kazunori; Kodama, Kazuhisa

    2011-01-01

    Summary Background and objectives Chronic kidney disease (CKD) is a risk factor of cardiovascular disease. The number of yellow plaques is a predictor of future cardiovascular events. We assumed that CKD might raise the risk of cardiovascular events by increasing the number of yellow plaques. Therefore, we compared the number of yellow plaques between patients with and without CKD. Design, setting, participants, & measurements Consecutive 136 patients with acute myocardial infarction who received percutaneous coronary intervention (PCI) and angioscopic examination were analyzed. The infarct-related artery was angioscopically examined. The number of yellow plaques, maximum yellow color grade of detected yellow plaques, and prevalence of disrupted yellow plaques in nonculprit segments were compared between patients with and without CKD. Results The number of yellow plaques was significantly larger in CKD than in non-CKD patients (median [interquartile range]: 4.0 [2.0 to 6.0] versus 2.0 [1.0 to 4.0], P = 0.001). Maximum yellow color grade and prevalence of disrupted plaques in the nonculprit segments were not different between patients with and without CKD. Multivariate logistic regression analysis revealed CKD as an independent risk of multiple yellow plaques per vessel (odds ratio 3.49, 95% confidence interval 1.10 to 11.10, P = 0.03). Conclusion CKD was an independent risk factor of multiple coronary yellow plaques, suggesting that patients with CKD would have a higher risk of coronary events because they had more yellow plaques than patients without CKD. PMID:22157709

  10. Plaque distribution and vascular remodeling of ruptured and nonruptured coronary plaques in the same vessel: an intravascular ultrasound study in vivo

    Microsoft Academic Search

    Clemens von Birgelen; Wolfgang Klinkhart; Gary S Mintz; Alexandra Papatheodorou; Jörg Herrmann; Dietrich Baumgart; Michael Haude; Heinrich Wieneke; Junbo Ge; Raimund Erbel

    2001-01-01

    OBJECTIVESThis study was designed to identify potential differences between the intravascular ultrasound (IVUS) characteristics of spontaneously ruptured and nonruptured coronary plaques.BACKGROUNDThe identification of vulnerable plaques in vivo may allow targeted prevention of acute coronary events and more effective evaluation of novel therapeutic approaches.METHODSIntravascular ultrasound was used to identify 29 ruptured plaques in arteries containing another nonruptured plaque in an adjacent

  11. Assessment of plaque assay methods for alphaviruses.

    PubMed

    Juarez, Diana; Long, Kanya C; Aguilar, Patricia; Kochel, Tadeusz J; Halsey, Eric S

    2013-01-01

    Viruses from the Alphavirus genus are responsible for numerous arboviral diseases impacting human health throughout the world. Confirmation of acute alphavirus infection is based on viral isolation, identification of viral RNA, or a fourfold or greater increase in antibody titers between acute and convalescent samples. In convalescence, the specificity of antibodies to an alphavirus may be confirmed by plaque reduction neutralization test. To identify the best method for alphavirus and neutralizing antibody recognition, the standard solid method using a cell monolayer overlay with 0.4% agarose and the semisolid method using a cell suspension overlay with 0.6% carboxymethyl cellulose (CMC) overlay were evaluated. Mayaro virus, Una virus, Venezuelan equine encephalitis virus (VEEV), and Western equine encephalitis virus (WEEV) were selected to be tested by both methods. The results indicate that the solid method showed consistently greater sensitivity than the semisolid method. Also, a "semisolid-variant method" using a 0.6% CMC overlay on a cell monolayer was assayed for virus titration. This method provided the same sensitivity as the solid method for VEEV and also had greater sensitivity for WEEV titration. Modifications in plaque assay conditions affect significantly results and therefore evaluation of the performance of each new assay is needed. PMID:23085307

  12. Clinical classification of plaque morphology in coronary disease.

    PubMed

    Otsuka, Fumiyuki; Joner, Michael; Prati, Francesco; Virmani, Renu; Narula, Jagat

    2014-07-01

    In published post-mortem pathological studies, more than two-thirds of acute coronary events are associated with the rupture of lipid-rich, voluminous, and outwardly remodelled plaques covered by attenuated and inflamed fibrous caps in the proximal part of coronary arteries. Superficial erosion of the plaques is responsible for most of the remaining events; the eroded plaques usually do not demonstrate much lipid burden, do not have thin fibrous caps, are not positively remodelled, and are not critically occlusive. Both noninvasive and invasive imaging studies have been performed to clinically define the plaque characteristics in acute coronary syndromes in an attempt to identify the high-risk plaque substrate susceptible to development of an acute coronary event. Optical coherence tomography (OCT)--an intravascular imaging modality with high resolution--can be used to define various stages of plaque morphology, which might allow its use for the identification of high-risk plaques vulnerable to rupture, and their amenability to pre-emptive interventional treatment. OCT might also be employed to characterize plaque pathology at the time of intervention, to provide a priori knowledge of the mechanism of the acute coronary syndrome and, therefore, to enable improved management of the condition. PMID:24776706

  13. Aggregative Behavior of Bacteria Isolated from Canine Dental Plaque

    Microsoft Academic Search

    David R. Elliott; Michael Wilson; Catherine M. F. Buckley; David A. Spratt

    2006-01-01

    Interbacterial adhesion of bacteria isolated from canine dental plaque was assessed by performing a visual coaggregation assay. Using conditions mimicking those likely to be encountered in vivo, the entire cultivable plaque microbiota from a single dog was assessed, and eight (6.7%) unique coaggregation interactions were detected for 120 crosses. Transmission electron microscopy was used to visualize several of the bacteria

  14. Characterization of bacteriophage communities and CRISPR profiles from dental plaque

    PubMed Central

    2014-01-01

    Background Dental plaque is home to a diverse and complex community of bacteria, but has generally been believed to be inhabited by relatively few viruses. We sampled the saliva and dental plaque from 4 healthy human subjects to determine whether plaque was populated by viral communities, and whether there were differences in viral communities specific to subject or sample type. Results We found that the plaque was inhabited by a community of bacteriophage whose membership was mostly subject-specific. There was a significant proportion of viral homologues shared between plaque and salivary viromes within each subject, suggesting that some oral viruses were present in both sites. We also characterized Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) in oral streptococci, as their profiles provide clues to the viruses that oral bacteria may be able to counteract. While there were some CRISPR spacers specific to each sample type, many more were shared across sites and were highly subject specific. Many CRISPR spacers matched viruses present in plaque, suggesting that the evolution of CRISPR loci may have been specific to plaque-derived viruses. Conclusions Our findings of subject specificity to both plaque-derived viruses and CRISPR profiles suggest that human viral ecology may be highly personalized. PMID:24981669

  15. A comparative study on plaque vulnerability using constitutive equations.

    PubMed

    Karimi, A; Navidbakhsh, M; Faghihi, S

    2014-03-01

    Atherosclerosis is the most serious and common form of cardiovascular disease in which plaque builds up inside the arteries. Peak plaque stress is considered as the main reason for plaque rupture, which results in heart attack and stroke. In the current research, the finite element method is used to anticipate plaque vulnerability, using human samples. A total of 23 healthy and atherosclerotic human coronary arteries (14 healthy and 9 atherosclerotic) were removed within 5 h postmortem. The samples were mounted on a uniaxial tensile test machine and the obtained mechanical properties were used in finite element models. The peak plaque stresses for the Ogden hyperelastic model were compared to the Mooney-Rivlin and Neo-Hookean outcomes. The results indicated that hypocellular plaque in all three models has the highest stress values compared to the cellular and calcified ones and, as a result, is quite prone to rupture. The calcified plaque type, in contrast, has the lowest stress values and remains stable. The results can be used in plaque vulnerability prediction and have clinical implications for interventions and surgeries such as balloon-angioplasty, cardiopulmonary bypass and stenting. PMID:23999817

  16. Bidirectional reflectance of dry and submerged Labsphere Spectralon plaque

    Microsoft Academic Search

    Kenneth J. Voss; Hao Zhang

    2006-01-01

    We present the bidirectional reflectance of a Labsphere calibration plaque, both dry and submerged in water, at normal illumination. The measurements indicate that when submerged in water, the Labsphere calibration plaque has a higher reflectance value than when dry at viewing angles below 55°. The results are presented in the form of a reflectance factor and are useful for calibrating

  17. To order wood plaques of ARTICLES or ISSUE COVERS,

    E-print Network

    Cai, Long

    ://www.myplaques.com/plaquebuilder/?jobid=75716 Paid by: __ Check/Money Order enclosed __ Invoice under Purchase Order Number __ VAT Numbercm) $1,030 / £668 ______ ____________ PLAQUE COLOR: __ Black Matte __ Cherry __Oak PLATE COLOR: __ Black on Brass __ Black on Silver __ Brass on Black PLAQUE FONT: __Arial __ Times * Please add $100

  18. Complement factor C5a induces atherosclerotic plaque disruptions

    PubMed Central

    Wezel, Anouk; de Vries, Margreet R; Lagraauw, H Maxime; Foks, Amanda C; Kuiper, Johan; Quax, Paul HA; Bot, Ilze

    2014-01-01

    Complement factor C5a and its receptor C5aR are expressed in vulnerable atherosclerotic plaques; however, a causal relation between C5a and plaque rupture has not been established yet. Accelerated atherosclerosis was induced by placing vein grafts in male apoE?/? mice. After 24 days, when advanced plaques had developed, C5a or PBS was applied locally at the lesion site in a pluronic gel. Three days later mice were killed to examine the acute effect of C5a on late stage atherosclerosis. A significant increase in C5aR in the plaque was detectable in mice treated with C5a. Lesion size and plaque morphology did not differ between treatment groups, but interestingly, local treatment with C5a resulted in a striking increase in the amount of plaque disruptions with concomitant intraplaque haemorrhage. To identify the potential underlying mechanisms, smooth muscle cells and endothelial cells were treated in vitro with C5a. Both cell types revealed a marked increase in apoptosis after stimulation with C5a, which may contribute to lesion instability in vivo. Indeed, apoptosis within the plaque was seen to be significantly increased after C5a treatment. We here demonstrate a causal role for C5a in atherosclerotic plaque disruptions, probably by inducing apoptosis. Therefore, intervention in complement factor C5a signalling may be a promising target in the prevention of acute atherosclerotic complications. PMID:25124749

  19. Bidirectional reflectance of dry and submerged Labsphere Spectralon plaque

    NASA Astrophysics Data System (ADS)

    Voss, Kenneth J.; Zhang, Hao

    2006-10-01

    We present the bidirectional reflectance of a Labsphere calibration plaque, both dry and submerged in water, at normal illumination. The measurements indicate that when submerged in water, the Labsphere calibration plaque has a higher reflectance value than when dry at viewing angles below 55°. The results are presented in the form of a reflectance factor and are useful for calibrating underwater reflectance measurements.

  20. Are herbal mouthwash efficacious over chlorhexidine on the dental plaque?

    PubMed Central

    Gupta, Devanand; Nayan, Swapna; Tippanawar, Harshad K.; Patil, Gaurav I.; Jain, Ankita; Momin, Rizwan K.; Gupta, Rajendra Kumar

    2015-01-01

    Aim: To compare the effect of herbal extract mouthwash and chlorhexidine mouthwash on the dental plaque level. Materials and Methods: The subjects (60 healthy medical students aged ranges between 20 and 25 years) were randomly divided into two groups, that is, the herbal group and the chlorhexidine gluconate mouthwash group. The data were collected at the baseline and 3 days. The plaque was disclosed using erythrosine disclosing agent and their scores were recorded using the Quigley and Hein plaque index modified by Turesky-Gilmore-Glickman. Statistical analysis was carried out later to compare the effect of all the two groups. Results: Our result showed that the chlorhexidine group shows a greater decrease in plaque score followed by herbal extract, but the result was statistically insignificant. Conclusion: The results indicate that herbal mouthwash may prove to be an effective agent owing to its ability to reduce plaque level, especially in low socioeconomic strata.

  1. Atherosclerotic plaque destabilization: mechanisms, models, and therapeutic strategies.

    PubMed

    Silvestre-Roig, Carlos; de Winther, Menno P; Weber, Christian; Daemen, Mat J; Lutgens, Esther; Soehnlein, Oliver

    2014-01-01

    Understanding the pathophysiology of atherogenesis and the progression of atherosclerosis have been major goals of cardiovascular research during the previous decades. However, the complex molecular and cellular mechanisms underlying plaque destabilization remain largely obscure. Here, we review how lesional cells undergo cell death and how failed clearance exacerbates necrotic core formation. Advanced atherosclerotic lesions are further weakened by the pronounced local activity of matrix-degrading proteases as well as immature neovessels sprouting into the lesion. To stimulate translation of the current knowledge of molecular mechanisms of plaque destabilization into clinical studies, we further summarize available animal models of plaque destabilization. Based on the molecular mechanisms leading to plaque instability, we outline the current status of clinical and preclinical trials to induce plaque stability with a focus on induction of dead cell clearance, inhibition of protease activity, and dampening of inflammatory cell recruitment. PMID:24385514

  2. Characterization of Atherosclerotic Plaques by Laser Speckle Imaging

    PubMed Central

    Nadkarni, Seemantini K.; Bouma, Brett E.; Helg, Tina; Chan, Raymond; Halpern, Elkan; Chau, Alexandra; Minsky, Milan Singh; Motz, Jason T.; Houser, Stuart L.; Tearney, Guillermo J.

    2010-01-01

    Background A method capable of determining atherosclerotic plaque composition and measuring plaque viscoelasticity can provide valuable insight into intrinsic features associated with plaque rupture and can enable the identification of high-risk lesions. In this article, we describe a new optical technique, laser speckle imaging (LSI), that measures an index of plaque viscoelasticity. We evaluate the potential of LSI for characterizing atherosclerotic plaque. Methods and Results Time-varying helium-neon laser speckle images were acquired from 118 aortic plaque specimens from 14 human cadavers under static and deforming conditions (0 to 200 ?m/s). Temporal fluctuations in the speckle patterns were quantified by exponential fitting of the normalized cross-correlation of sequential frames in each image series of speckle patterns to obtain the exponential decay time constant, ?. The decorrelation time constants of thin-cap fibroatheromas (TCFA) (?=47.5±19.2 ms) were significantly lower than those of other atherosclerotic lesions (P<0.001), and the sensitivity and specificity of the LSI technique for identifying TCFAs were >90%. Speckle decorrelation time constants demonstrated strong correlation with histological measurements of plaque collagen (R=0.73, P<0.0001), fibrous cap thickness (R=0.87, P<0.0001), and necrotic core area (R=?0.81, P<0.0001). Under deforming conditions (10 to 200 ?m/s), ? correlated well with cap thickness in necrotic core fibroatheromas (P>0.05). Conclusions The measurement of speckle decorrelation time constant from laser speckle images provides an index of plaque viscoelasticity and facilitates the characterization of plaque type. Our results demonstrate that LSI is a highly sensitive technique for characterizing plaque and identifying thin-cap fibroatheromas. PMID:16061738

  3. Aortic Arch Plaques and Risk of Recurrent Stroke and Death

    PubMed Central

    Di Tullio, Marco R.; Russo, Cesare; Jin, Zhezhen; Sacco, Ralph L.; Mohr, J.P.; Homma, Shunichi

    2010-01-01

    Background Aortic arch plaques are a risk factor for ischemic stroke. Although the stroke mechanism is conceivably thromboembolic, no randomized studies have evaluated the efficacy of antithrombotic therapies in preventing recurrent events. Methods and Results The relationship between arch plaques and recurrent events was studied in 516 patients with ischemic stroke, double–blindly randomized to treatment with warfarin or aspirin as part of the Patent Foramen Ovale in Cryptogenic Stroke Study (PICSS), based on the Warfarin-Aspirin Recurrent Stroke Study (WARSS). Plaque thickness and morphology was evaluated by transesophageal echocardiography. End-points were recurrent ischemic stroke or death over a 2-year follow-up. Large plaques (?4mm) were present in 19.6% of patients, large complex plaques (those with ulcerations or mobile components) in 8.5 %. During follow-up, large plaques were associated with a significantly increased risk of events (adjusted Hazard Ratio 2.12, 95% Confidence Interval 1.04-4.32), especially those with complex morphology (HR 2.55, CI 1.10-5.89). The risk was highest among cryptogenic stroke patients, both for large plaques (HR 6.42, CI 1.62-25.46) and large-complex plaques (HR 9.50, CI 1.92-47.10). Event rates were similar in the warfarin and aspirin groups in the overall study population (16.4% vs. 15.8%; p=0.43). Conclusions In patients with stroke, and especially cryptogenic stroke, large aortic plaques remain associated with an increased risk of recurrent stroke and death at two years despite treatment with warfarin or aspirin. Complex plaque morphology confers a slight additional increase in risk. PMID:19380621

  4. Systematic review of pleural plaques and lung function

    PubMed Central

    Kerper, Laura E.; Lynch, Heather N.; Zu, Ke; Tao, Ge; Utell, Mark J.

    2015-01-01

    Abstract Context US EPA proposed a Reference Concentration for Libby amphibole asbestos based on the premise that pleural plaques are adverse and cause lung function deficits. Objective We conducted a systematic review to evaluate whether there is an association between pleural plaques and lung function and ascertain whether results were dependent on the method used to identify plaques. Methods Using the PubMed database, we identified studies that evaluated pleural plaques and lung function. We assessed each study for quality, then integrated evidence and assessed associations based on the Bradford Hill guidelines. We also compared the results of HRCT studies to those of X-ray studies. Results We identified 16 HRCT and 36 X-ray studies. We rated six HRCT and 16 X-ray studies as higher quality based on a risk-of-bias analysis. Half of the higher quality studies reported small but statistically significant mean lung function decrements associated with plaques. None of the differences were clinically significant. Many studies had limitations, such as inappropriate controls and/or insufficient adjustment for confounders. There was little consistency in the direction of effect for the most commonly reported measurements. X-ray results were more variable than HRCT results. Pleural plaques were not associated with changes in lung function over time in longitudinal studies. Conclusion The weight of evidence indicates that pleural plaques do not impact lung function. Observed associations are most likely due to unidentified abnormalities or other factors. PMID:25518994

  5. Bone marrow endothelial progenitors in atherosclerotic plaque resolution

    PubMed Central

    Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Barlic-Dicen, Jana

    2013-01-01

    Atherosclerosis is a major cause of morbidity and mortality in the United States. Persistently elevated circulating low-density lipoprotein, or hypercholesterolemia, and deposition of low-density lipoprotein in the vascular wall are the main inducers of atherosclerosis, which manifests itself as arterial lesions or plaques. Some plaques become thrombosis-prone and rupture, causing acute myocardial infarction or stroke. Lowering plasma cholesterol through the use of statins is the primary intervention against atherosclerosis. Treatment with statins slows progression of atherosclerosis but can only support limited plaque regression. Partially regressed plaques continue to pose a serious threat due to their remaining potential to rupture. Thus, new interventions inducing complete reversal of atherosclerosis are being sought. Implementation of new therapies will require clear understanding of the mechanisms driving plaque resolution. In this Commentary, we highlight the role of bone marrow endothelial progenitors in atherosclerotic plaque regression and discuss how regenerative cell-based interventions could be used in combination with plasma lipid-lowering to induce plaque reversal in order to prevent and/or reduce adverse cardiovascular events. PMID:23538778

  6. Metal plaque on reeds from an Acid mine drainage site.

    PubMed

    Guo, Lin; Cutright, Teresa J

    2015-05-01

    Studies were conducted to investigate the interactions among rhizosphere microorganisms, plaque formation, and metal accumulation in reeds [ (Cav.) Trin. ex Steud.] grown in an acid mine drainage-contaminated field. We found that Fe(II)-oxidizing bacteria (Fe(II)OB] played a key role in Fe plaque formation and pH decrease. The kinetics of Fe plaque formation were related to the abundance of rhizosphere Fe(II)OB, which mediated 66.0 to 93.3% Fe(II) oxidation. The Fe(II) concentration decreased from 14.24 to 0.94 mg L in nonsterile samples, with the most abundant Fe(II)OB activity (5.64 ± 3.83 × 10 colony-forming units g) after 2 d, and pH decreased from 2.91 to 2.50. The amount of metal plaque was also positively correlated with metal levels in soil. No significant correlations were found between Fe, Mn, and Al concentration in the plaque. Reeds sequestered Al in the aboveground tissues, and Mn and Al were stored in the roots and rhizomes. Metal plaque did not affect the Mn uptake but inhibited the translocation of Fe and Al in reeds. To increase the phytoremediation efficiency of Fe, Mn, and Al from the acid mine drainage-contaminated site, further research may be needed to inhibit the Fe(II)OB growth and reduce the metal plaque formation, thereby increasing the metal accumulation in reeds. PMID:26024266

  7. Dural lucent line: characteristic sign of hyperostosing meningioma en plaque

    SciTech Connect

    Kim, K.S.; Rogers, L.F.; Lee, C.

    1983-12-01

    Hyperostosis of the skull associated with en plaque form of meningioma may present a diagnostic challenge, since the intracranial part of the tumor is not visualized by skull radiography, computed tomography (CT), or other neuroradiologic methods. The authors report four cases of hyperostosing meningioma en plaque demonstrating a characteristic feature: a subdural layer of ossification along the hyperostotic bone with a dural lucent interface. Polytomography or high-resolution CT at bone window settings is necessary to identify the dural lucent line. The absence of this sign does not exclude meningioma en plaque.

  8. Complement activation in amyloid plaques in Alzheimer’s dementia

    Microsoft Academic Search

    P. Eikelenboom; C. E. Hack; J. M. Rozemuller; F. C. Stam

    1988-01-01

    Summary  Amyloid plaques in Alzheimer’s dementia contain complement factors C1q, C4 and C3. In the present study we demonstrate complement\\u000a activation in amyloid plaques using immunoenzymatical techniques and specific antibodies against subunits of individual complement\\u000a components and activated complement products. Amyloid plaques contain C1q and activated C3 fragments (C3c and C3d, g) but\\u000a no C1s and C3a. These findings demonstrate that

  9. Detection of Atherosclerotic Coronary Plaques by Fluorescence Lifetime Imaging Angioscopy

    E-print Network

    Thomas, Patrick A.

    2010-10-12

    the potential of a FLIM angioscopy system to detect and differentiate coronary atherosclerotic plaques ex-vivo into several groups including thin, fibrotic, lipid-laden, thick-cap fibroatheroma (FA), and fibrocalcified. Samples were extracted post-mortem weekly...

  10. 32. STUDIO VIEW OF PLAQUE PLACED ON MILL HOUSE AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. STUDIO VIEW OF PLAQUE PLACED ON MILL HOUSE AT TIME OF COMPLETION, COMMEMORATING EDWARD J. LUKE (SEE TEXT) - Sperry Corn Elevator Complex, Weber Avenue (North side), West of Edison Street, Stockton, San Joaquin County, CA

  11. 26. BOLLING MEMORIAL GROVE PLAQUE, AVENUE OF THE GIANTS, OLD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. BOLLING MEMORIAL GROVE PLAQUE, AVENUE OF THE GIANTS, OLD HIGHWAY 101. HUMBOLDT COUNTY, CALIFORNIA. LOOKING E. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

  12. 8. DETAIL OF EAST FRONT, SHOWING COMPANY NAME PLAQUE AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. DETAIL OF EAST FRONT, SHOWING COMPANY NAME PLAQUE AND PARAPET. VIEW TO SOUTHWEST. - Commercial & Industrial Buildings, Carr, Ryder & Adams Company, Powerhouse, Tenth & Jackson Streets, Dubuque, Dubuque County, IA

  13. 6. WEST FRONT DETAIL, SHOWING COMPANY NAME PLAQUE AND UPPER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. WEST FRONT DETAIL, SHOWING COMPANY NAME PLAQUE AND UPPER FLOOR FENESTRATION. VIEW TO EAST. - Commercial & Industrial Buildings, Becker-Hazelton Company Warehouse, 280 Iowa Street, Dubuque, Dubuque County, IA

  14. 10. VIEW OF PLAQUE ON ILLINOIS DEPARTMENT OF TRANSPORTATION HEADQUARTERS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW OF PLAQUE ON ILLINOIS DEPARTMENT OF TRANSPORTATION HEADQUARTERS GROUND, SPRINGFIELD, ILLINOIS; NOW IN CUSTODY OF WARREN COUNTY HIGHWAY SUPERINTENDENT - Campbell Bridge, Spanning Cedar Creek at Sumner Township Road 22, Little York, Warren County, IL

  15. 6. VIEW OF COMMEMORATIVE PLAQUE, EAST APPROACH GUARDRAIL, WHICH STATES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW OF COMMEMORATIVE PLAQUE, EAST APPROACH GUARDRAIL, WHICH STATES 'SALINE RIVER; ARK. GENERAL CONST. CO.; CONTRACTOR; ARKANSAS; STATE HIGHWAY DEPARTMENT; 1928, BRIDGE NO. __.' - Saline River Bridge, County Highway 365 across Saline River, Benton, Saline County, AR

  16. Asbestos related pleural plaques in retired boiler room workers.

    PubMed

    Hsiao, T M; Ho, C K; Su, W P; Hwang, J J; Tsai, M S; Chau, T T; Lu, S N; Chang, W Y

    1993-02-01

    Occupational disease is often underestimated and only a few formal reports have been published in Taiwan. This study reports of a group of workers with asbestos-induced-disease, pleural plaque in Taiwan. Pleural plaque is a marker of exposure to asbestos. The disease was found in chest radiographs of five boiler room workers in a sugar refining factory. The chest radiographs of 248 current workers in that plant were reviewed, and none of them was found to have pleural plaques. The storage of asbestos and the long-time use of mixed asbestos cement for insulation of the inner wall of the stove and pipes were found in the factory. The authors believe that the pleural plaques might be resulted from occupational exposure to asbestos. It is suggested that the use of asbestos should be prohibited, step by step, and regular follow-up of the workers with an asbestos exposure history is required. PMID:8492355

  17. Proteolytic enzymes and rotavirus SA-11 plaque formation.

    PubMed Central

    Ramia, S; Sattar, S A

    1980-01-01

    In addition to trypsin, eight other proteolytic enzyme preparations were tested for their ability to assist simian rotavirus SA-11 plaque formation in MA-104 cells. When incorporated in the overlay (minimal essential medium and 0.7% Ionagar No. 2) in the concentrations per mL indicated, alpha-chymotrypsin (10 micrograms), elastase (0.5 micrograms), subtilisin (0.5 micrograms), pronase (2.5 micrograms) and pancreatin (25 micrograms) were as efficient as trypsin (5 micrograms) in helping SA-11 produce 3-4 mm diameter plaques after five days of incubation at 37 degrees C. No plaques were produced when pepsin (25 micrograms), papain (10 micrograms) or thermolysin (10 micrograms) was added to the overlay. Addition of soybean trypsin inhibitor to alpha-chymotrypsin-, pronase- or pancreatin-containing overlays completely inhibited virus plaque production. A similar effect was not seen with elastase or subtilisin. PMID:6250685

  18. Clathrin and Cx43 gap junction plaque endoexocytosis

    SciTech Connect

    Nickel, Beth M.; DeFranco, B. Hewa; Gay, Vernon L. [Department of Cell Biology and Physiology, University of Pittsburgh, School of Medicine, 324 South Biomedical Science Tower, Pittsburgh, PA 15261 (United States); Murray, Sandra A. [Department of Cell Biology and Physiology, University of Pittsburgh, School of Medicine, 324 South Biomedical Science Tower, Pittsburgh, PA 15261 (United States)], E-mail: smurray@pitt.edu

    2008-10-03

    In earlier transmission electron microscopic studies, we have described pentilaminar gap junctional membrane invaginations and annular gap junction vesicles coated with short, electron-dense bristles. The similarity between these electron-dense bristles and the material surrounding clathrin-coated pits led us to suggest that the dense bristles associated with gap junction structures might be clathrin. To confirm that clathrin is indeed associated with annular gap junction vesicles and gap junction plaques, quantum dot immuno-electron microscopic techniques were used. We report here that clathrin associates with both connexin 43 (Cx43) gap junction plaques and pentilaminar gap junction vesicles. An important finding was the preferential localization of clathrin to the cytoplasmic surface of the annular or of the gap junction plaque membrane of one of the two contacting cells. This is consistent with the possibility that the direction of gap junction plaque internalization into one of two contacting cells is regulated by clathrin.

  19. Elevation view of dedication plaque on east wall of south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Elevation view of dedication plaque on east wall of south lobby - National Home for Disabled Volunteer Soldiers, Pacific Branch, Main Mental Health Building, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  20. Detail of plaque beneath column on the south parapet at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of plaque beneath column on the south parapet at the west end of the bridge. The plaque reads ?1914; Mayor E.J. Drussel; Councilmen E.S. Henry, E.F. Hogan, R.P. Lamdin, C.F. Ross, J.H. Shuppert; Leonard & Day, Engineers; C.H. Gildersleeve, Builder.? - First Street Bridge, Spanning Napa River at First Street between Soscol Avenue & Juarez Street, Napa, Napa County, CA

  1. Single-use plaque removal efficacy of three power toothbrushes.

    PubMed

    Sharma, N C; Goyal, C R; Qaqish, J G; Cugini, M A; Thompson, M C; Warren, P R

    2005-06-01

    OBJECTIVES.: To compare the safety and plaque removal efficacy of two oscillating/rotating/pulsating toothbrushes (Oral-B ProfessionalCaretrade mark 7000 [PC 7000] and Oral-B 3D Excel [3DE]) and a high-frequency toothbrush (Sonicare(R) Advance, Philips Oral Healthcare; SA) in a single-use, examiner-blind, three period crossover study. METHODS.: After refraining from all oral hygiene procedures for 23-25 hours, subjects received an oral tissue examination and those with pre-brushing whole mouth mean plaque scores 0.6 based on the Rustogi et al. Modified Navy Plaque Index were randomly assigned to treatment sequence. After brushing with the assigned toothbrush and a commercially available dentifrice for 2 minutes, oral tissues were then re-examined and post-brushing plaque scores recorded. Following a brief washout period between two additional visits, the above procedures were repeated with the two alternate toothbrushes. One examiner, blinded to the treatment sequence, performed all clinical measurements. RESULTS.: A total of 79 subjects (28 males and 51 females) were enrolled and completed the study. Each toothbrush was found to be safe and significantly reduced plaque levels after a single brushing. The PC 7000 and 3DE were equally more effective in plaque removal than the SA, at all tooth areas, reducing plaque by 59.0%, 59.7% and 51.8%, respectively on whole mouth surfaces, and by 67.5%, 67.8% and 59.4%, respectively on approximal surfaces. CONCLUSIONS.: The action of the oscillating/rotating/pulsating toothbrushes (Oral-B ProfessionalCare 7000 and Oral-B 3D Excel) was more effective in plaque removal than the high-frequency toothbrush (Sonicare Advance). PMID:16253750

  2. Tryptase Promotes Atherosclerotic Plaque Haemorrhage in ApoE-/- Mice

    PubMed Central

    Tian, Dai; Li, Xiaobo; Ning, Yanxia; Yin, Lianhua

    2013-01-01

    Tryptase, the most abundant mast cell (MC) granule protein, plays an important role in atherosclerosis plaque development. To test the hypothesis that tryptase participates directly in atherosclerosis plaque haemorrhage, the gene sequence and siRNA for tryptase were cloned into a lentivirus carrier and atherosclerosis plaque haemorrhage models in ApoE-/- mice were constructed. After a cuffing-cervical artery operation, the mice were randomly divided into 6 groups. Hematoxylin and eosin(HE) staining showed that the cervical artery plaque area was much larger in the tryptase overexpression group compared to the other groups, and there was greater artery stenosis. The artery stenosis from the cuff-side in all groups was more than 90%, except the siRNA group. Tryptase promotes plaque haemorrhage distinctively because 50% of the mice in the tryptase overexpression group had plaque haemorrhage, while only 10% in the siRNA group did. The immunohistochemistry of the cervical artery plaque showed that plasminogen activator inhibitor-1 (PAI-1) expression was the lowest while tissue plasminogen activator (tPA), CD31, CD34 and VEGF was the highest in the tryptase overexpression groups. This observation was completely contrary to what was observed in the siRNA group. Tryptase promoted bEnd.3 cell growth, migration and capillary-like tube formation, which suggests that tryptase can promote microvessel angiogenesis. PAI-1 expression was inhibited, while tPA expression was increased by tryptase in bEnd.3 cells. Our in vivo and in vitro studies suggest that trypase can promote atherosclerotic plaque haemorrhage by promoting angiogenesis and regulating the balance of PAI-1 and tPA. Thus, regulating tryptase expression in MCs may provide a potential target for atherosclerosis treatment. PMID:23573292

  3. Effect of pancreatin on plaque formation by influenza viruses

    Microsoft Academic Search

    Paul E. Came; Andrea Pascale; Gerard Shimonaski

    1968-01-01

    Summary Pancreatin incorporated into the overlay medium of chick embryo monolayers infected with influenza A\\/Swine, A\\/PR8, A\\/NWS, A2\\/Jap. 305\\/57, B\\/Lee, and B\\/GL enhances the number and size of plaques. The influenza A2\\/RI\\/5+ and A2\\/RI\\/5- substrains were not affected. In general, the degree of enhancement and the efficiency of plaque formation varies as the concentration of pancreatin is increased. It is

  4. Ultrashort echo time cardiovascular magnetic resonance of atherosclerotic carotid plaque

    Microsoft Academic Search

    Cheuk F Chan; Niall G Keenan; Sonia Nielles-Vallespin; Peter Gatehouse; Mary N Sheppard; Joseph J Boyle; Dudley J Pennell; David N Firmin

    2010-01-01

    BACKGROUND: Multi-contrast weighted cardiovascular magnetic resonance (CMR) allows detailed plaque characterisation and assessment of plaque vulnerability. The aim of this preliminary study was to show the potential of Ultra-short Echo Time (UTE) subtraction MR in detecting calcification. METHODS: 14 ex-vivo human carotid arteries were scanned using CMR and CT, prior to histological slide preparation. Two images were acquired using a

  5. Tazarotene gel: Efficacy and safety in plaque psoriasis

    Microsoft Academic Search

    Gerald D. Weinstein

    1997-01-01

    Tazarotene is the first of a new generation of acetylenic retinoids developed for the topical treatment of mild-to-moderate plaque psoriasis. Controlled clinical trials have demonstrated that once-daily tazarotene 0.05% and 0.1% gels are effective in improving and reducing clinical signs and symptoms of psoriasis on trunk and limb lesions and difficult-to-treat elbow and knee plaques. Tazarotene has a rapid onset

  6. Antibacterial effect of taurolidine (2%) on established dental plaque biofilm

    Microsoft Academic Search

    Nicole Birgit Arweiler; Thorsten Mathias Auschill; Anton Sculean

    Preliminary data have suggested that taurolidine may bear promising disinfectant properties for the therapy of bacterial infections.\\u000a However, at present, the potential antibacterial effect of taurolidine on the supragingival plaque biofilm is unknown. To\\u000a evaluate the antibacterial effect of taurolidine on the supragingival plaque biofilm using the vital fluorescence technique\\u000a and to compare it with the effect of NaCl and

  7. Bidirectional reflectance of dry and submerged Labsphere Spectralon plaque.

    PubMed

    Voss, Kenneth J; Zhang, Hao

    2006-10-20

    We present the bidirectional reflectance of a Labsphere calibration plaque, both dry and submerged in water, at normal illumination. The measurements indicate that when submerged in water, the Labsphere calibration plaque has a higher reflectance value than when dry at viewing angles below 55 degrees . The results are presented in the form of a reflectance factor and are useful for calibrating underwater reflectance measurements. PMID:17068529

  8. Vulnerable plaque intervention: State of the art.

    PubMed

    Young, John J; Phillips, Harry R; Marso, Steven P; Granada, Juan F; McPherson, John A; Waksman, Ron; Steinhubl, Steven R; Schwartz, Robert S; Stone, Gregg W

    2008-02-15

    Progressive atherosclerotic disease is responsible for many of the late adverse clinical events that detract from the high procedural and clinical success of percutaneous coronary intervention. Despite recent advances in catheter based technology for the treatment of obstructive coronary artery disease, the greater risk to the patient over time may in fact come from the significant rate of acute coronary events triggered by nonculprit and/or nonobstructive coronary artery lesions. These areas of vulnerability within the epicardial coronary tree have generated a great deal of interest surrounding the concepts of vulnerable plaque (VP), vulnerable blood and the vulnerable patient. This 'state of the art' review discusses the limitations of coronary angiography alone in providing risk assessment; reviews the underlying biological concepts of VP; discusses evolving noninvasive and invasive imaging technologies for the detection of VP; and finally provides a futuristic look at how the field of interventional cardiology may transcend the traditional angiogram and move toward a more comprehensive treatment approach that benefits the patients' overall coronary health. PMID:18288729

  9. Asbestos-related pleural plaques and lung function.

    PubMed

    Oliver, L C; Eisen, E A; Greene, R; Sprince, N L

    1988-01-01

    The present study examines the association between asbestos-related pleural plaques and lung function in a group of workers with occupational exposure to asbestos. Exposure, smoking, and respiratory histories, chest radiographs, flow-volume loops, and single breath DLCOs were obtained on 383 railroad workers. A score based on the ILO-1980 classification system was used to quantify the extent of plaquelike thickening. In order to eliminate potential confounders, we excluded from final analysis subjects with diffuse pleural thickening (n = 10) or small irregular opacities classified as profusion 0/1 or greater (n = 6) on chest radiograph. Definite pleural plaques were observed in 22.6%. The single breath DLCO was similar in the groups with and without plaques (p = 0.0550). Decrement in FVC and the occurrence of pulmonary restriction were associated with the presence of definite plaques (p = 0.0306 and 0.0431, respectively) and with quantitative pleural score (p = 0.0135 and 0.0126), controlling for duration of asbestos exposure and smoking. A test for trend revealed an association between level of diagnostic certainty (none, suspect, definite) for pleural plaques and these measures of lung function (p less than 0.02). Our findings reveal an association between asbestos-related pleural plaques and decrement in lung function as measured by FVC and criteria for pulmonary restriction. PMID:3266060

  10. Effects of dietary flaxseed on atherosclerotic plaque regression.

    PubMed

    Francis, Andrew A; Deniset, Justin F; Austria, Jose A; LaValleé, Renee K; Maddaford, Graham G; Hedley, Thomas E; Dibrov, Elena; Pierce, Grant N

    2013-06-15

    Dietary flaxseed can retard the progression of atherosclerotic plaques. However, it remains unclear whether these antiatherogenic effects extend to plaque regression. In the present study, the therapeutic potential of dietary flaxseed on atherosclerotic plaque regression and vascular contractile function was evaluated using a novel rabbit model. Rabbits were randomly assigned to receive either a regular diet for 12 wk (group I) or a 1% cholesterol-supplemented diet for 4 wk followed by a regular diet for 8 wk (group II). The remaining experimental animals were treated as in group II but were fed for an additional 14 wk with either a regular diet (group III) or a 10% flaxseed-supplemented diet (group IV). Animals in group II showed clear evidence of plaque growth stabilization. Their vessels also exhibited significantly lower norepinephrine-induced contraction and an impaired relaxation response to acetylcholine compared with animals in group I. Dietary flaxseed supplementation resulted in a significant ?40% reduction in plaque formation (P = 0.033). Animals in both groups II and III displayed improved contraction and endothelium-dependent vessel relaxation. Dietary flaxseed is a valuable strategy to accelerate the regression of atherosclerotic plaques; however, flaxseed intervention did not demonstrate a clear beneficial effect on the vessel contractile response and endothelium-dependent vasorelaxation. PMID:23585134

  11. Preliminary study of the detectability of coronary plaque with PET

    NASA Astrophysics Data System (ADS)

    Delso, G.; Martinez-Möller, A.; Bundschuh, R. A.; Nekolla, S. G.; Ziegler, S. I.; Schwaiger, M.

    2011-04-01

    The evaluation of coronary plaque vulnerability could be of great diagnostic value in cardiology. Positron emission tomography (PET) is a good candidate due to its ability to quantify micromolar concentrations of targeted drugs. However, the detectability of sub-voxel targets such as coronary plaque is limited by partial volume effects and by cardiorespiratory motion. The goal of this paper is to investigate the impact of these factors in the detectability of plaque uptake. Radioactive markers were implanted on the epicardium of a pig and in vivo scans were performed. This was complemented with phantom measurements to determine the minimum detectable uptake as a function of background activity. Simulations were used to evaluate the effect of cardiorespiratory motion on the reconstructed lesions. Despite cardiorespiratory motion of up to 7 mm, the markers were detectable in the in vivo scans even after the injection of background. A lower limit of 250 Bq was found for a target to be detectable. Motion reduced the contrast of the reconstructed lesions to 23% of their static counterpart. Respiratory gating improved this to 49% of the static value. The results suggest that coronary plaque evaluation with PET is possible, provided that sufficient plaque-to-myocardium uptake contrast (50 to 100) can be achieved. This requirement increases exponentially for lesions with uptake below 250 Bq. The described experiments provide a means of estimating the minimum uptake and contrast required to ensure the detectability of plaque lesions.

  12. Dosimetry for 125I seed (model 6711) in eye plaques.

    PubMed

    Chiu-Tsao, S T; Anderson, L L; O'Brien, K; Stabile, L; Liu, J C

    1993-01-01

    The effect of eye plaque materials (gold backing and silastic seed-carrier insert) on the dose distribution around a single 125I seed has been measured, using cubic lithium fluoride thermoluminescent dosimeters (TLDs) 1 mm on an edge, in a solid water eye phantom embedded in a solid water head phantom. With an 125I seed (model 6711) positioned in the center slot of the silastic insert for a 20-mm plaque of the design used in the collaborative ocular melanoma study (COMS), dose was measured at 2-mm intervals along the plaque central axis (the seed's transverse axis) and at various off-axis points, both with and without the COMS gold backing placed over the insert. Monte Carlo calculations (MORSE code) were performed, as well, for these configurations and closely the same geometry but assuming a large natural water phantom. Additional Monte Carlo calculations treated the case, both for 20- and 12-mm gold plaques, where the silastic insert is replaced by natural water. Relative to previous measurements taken in homogeneous medium of the same material (without the eye plaque), the dose reduction found by both Monte Carlo and TLD methods was greater at points farther from the seed along the central axis and, for a given central-axis depth, at larger off-axis distances. Removal of the gold backing from the plaque did not make measurable difference in the dose reduction results (10% at 1 cm). PMID:8497229

  13. Automatic plaque assay for the pharmaceutical industry using machine vision

    NASA Astrophysics Data System (ADS)

    Wilder, Joseph; Tsai, Augustine; Festa, J. M.

    1995-10-01

    A crucial step in the manufacture of vaccines is the verification of their potency. An assay of the potency must be carried out on every batch produced to determine the safety and efficacy of the vaccine. Currently, human inspectors count the number of plaques (holes) in a cell layer in a petri dish to estimate the potency.They must determine whether nearby plaques that have overgrown each other's borders are single or multiple plaques and distinguish between plaques and small tears in the cell layer resulting from the processing operations (the edges of tears differ in appearance from the edges of plaques). Because of the judgments required to make these subtle distinctions, human inspectors are inconsistent. In cooperation with Merck & Co., Inc., the Rutgers University Center for Computer Aids for Industrial Productivity has demonstrated the feasibility of achieving consistent automatic counting of plaques by a prototype intelligent machine vision system. The David Sarnoff Research Center developed materials handling equipment and factory information system interfaces to enable this prototype system to be installed in a quality control facility at Merck. This paper describes the overall operation of the machine vision aspects of the system, including optics, illumination, sensing, preprocessing, feature extraction and shape recognition. Results of initial tests of the system are also reported.

  14. Local critical stress correlates better than global maximum stress with plaque morphological features linked to atherosclerotic plaque vulnerability: an in vivo multi-patient study

    Microsoft Academic Search

    Dalin Tang; Zhongzhao Teng; Gador Canton; Thomas S Hatsukami; Li Dong; Xueying Huang; Chun Yuan

    2009-01-01

    BACKGROUND: It is believed that mechanical stresses play an important role in atherosclerotic plaque rupture process and may be used for better plaque vulnerability assessment and rupture risk predictions. Image-based plaque models have been introduced in recent years to perform mechanical stress analysis and identify critical stress indicators which may be linked to rupture risk. However, large-scale studies based on

  15. Macrophage-targeted photodynamic detection of vulnerable atherosclerotic plaque

    NASA Astrophysics Data System (ADS)

    Hamblin, Michael R.; Tawakol, Ahmed; Castano, Ana P.; Gad, Faten; Zahra, Touqir; Ahmadi, Atosa; Stern, Jeremy; Ortel, Bernhard; Chirico, Stephanie; Shirazi, Azadeh; Syed, Sakeena; Muller, James E.

    2003-06-01

    Rupture of a vulnerable atherosclerotic plaque (VP) leading to coronary thrombosis is the chief cause of sudden cardiac death. VPs are angiographically insignificant lesions, which are excessively inflamed and characterized by dense macrophage infiltration, large necrotic lipid cores, thin fibrous caps, and paucity of smooth muscle cells. We have recently shown that chlorin(e6) conjugated with maleylated albumin can target macrophages with high selectivity via the scavenger receptor. We report the potential of this macrophage-targeted fluorescent probe to localize in VPs in a rabbit model of atherosclerosis, and allow detection and/or diagnosis by fluorescence spectroscopy or imaging. Atherosclerotic lesions were induced in New Zealand White rabbit aortas by balloon injury followed by administration of a high-fat diet. 24-hours after IV injection of the conjugate into atherosclerotic or normal rabbits, the animals were sacrificed, and aortas were removed, dissected and examined for fluorescence localization in plaques by fiber-based spectrofluorimetry and confocal microscopy. Dye uptake within the aortas was also quantified by fluorescence extraction of samples from aorta segments. Biodistribution of the dye was studied in many organs of the rabbits. Surface spectrofluorimetry after conjugate injection was able to distinguish between plaque and adjacent aorta, between atherosclerotic and normal aorta, and balloon-injured and normal iliac arteries with high significance. Discrete areas of high fluorescence (up to 20 times control were detected in the balloon-injured segments, presumably corresponding to macrophage-rich plaques. Confocal microscopy showed red ce6 fluorescence localized in plaques that showed abundant foam cells and macrophages by histology. Extraction data on aortic tissue corroborated the selectivity of the conjugate for plaques. These data support the strategy of employing macrophage-targeted fluorescent dyes to detect VP by intravascular spectrofluorimetry. It may also be possible to use macrophage-targeted PDT to therapeutically modify inflammatory cell-laden VPs leading to plaque stabilization and reduction of sudden cardiovascular death.

  16. ROPES eye plaque dosimetry: commissioning and verification of an ophthalmic brachytherapy treatment planning system

    NASA Astrophysics Data System (ADS)

    Poder, J.; Annabell, N.; Geso, M.; Alqathami, M.; Corde, S.

    2013-06-01

    In this study, the Plaque SimulatorTM eye plaque brachytherapy planning system was commissioned for ROPES eye plaques and Amersham Health model 6711 Iodine 125 seeds, using TG43-UI data. The brachytherapy module of the RADCALC® independent checking program was configured to allow verification of the accuracy of the dose calculated by Plaque SimulatorTM. Central axis depth dose distributions were compared and observed to agree to within 2% for all ROPES plaque models and depths of interest. Experimental measurements were performed with a customized PRESAGEm 3-D type dosimeter to validate the calculated depth dose distributions. Preliminary results have shown the effect of the stainless steel plaque backing decreases the measured fluorescence intensity by up to 25%, and 40% for the 15 mm and 10 mm diameter ROPES plaques respectively. This effect, once fully quantified should be accounted for in the Plaque SimulatorTM eye plaque brachytherapy planning system.

  17. Detection of activated T lymphocytes in the human atherosclerotic plaque.

    PubMed Central

    Hansson, G. K.; Holm, J.; Jonasson, L.

    1989-01-01

    It was recently shown that the human atherosclerotic plaque contains significant amounts of T lymphocytes, and also that smooth muscle cells in these plaques express class II MHC (Ia) antigens. These antigens are not normally present on smooth muscle cells but are inducible by interferon-gamma, a secretory product of activated T cells. Therefore, T cell activation in the plaque was analyzed by immunofluorescent detection of activation markers on T cells isolated from the plaques and in cryostat sections of carotid endarterectomy specimens. Of cells isolated from the plaque, 5% exhibited the E rosettes characteristic of T cells. One third of these cells expressed HLA-DR and VLA-1 (very late activation antigen-1), which in T cells are synthesized only in the activated state. T cells were also identified in sections using immunofluorescent detection of the T cell-specific surface protein, CD3 (Leu-4), with rhodamine labeled second-step antibodies. The frequency of activated T cells was then determined by staining the same, or serial, sections with antibodies to HLA-DR or to the interleukin-2 receptor, followed by biotin-avidin-FITC detection. Of the T cells in the plaque, 34% and 6%, respectively, expressed these cell surface proteins. Taken together, these results indicated that a substantial proportion of the T cells in atherosclerotic plaque are in an activated state. The activation pattern, with a high frequency of HLA-DR and VLA-1 expression and a much lower frequency of interleukin-2 receptor expression, was similar to that reported to occur in chronic inflammatory conditions. Interferon-gamma could be detected in and around some of the lymphocytes, suggesting that paracrine secretion of this lymphokine may occur in the plaque. T cells may be activated locally, presumably by antigen(s) presented in the context of class II MHC expressing smooth muscle cells and/or macrophages, in the atherosclerotic lesion. Such activated T cells may in turn modulate the functions of other cells in the plaque. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:2505620

  18. Echogenic carotid plaques are associated with aortic arterial stiffness in subjects with subclinical carotid atherosclerosis.

    PubMed

    Zureik, Mahmoud; Bureau, Jeanne-Marie; Temmar, Mohammed; Adamopoulos, Chris; Courbon, Dominique; Bean, Kathryn; Touboul, Pierre-Jean; Benetos, Athanase; Ducimetière, Pierre

    2003-03-01

    A better understanding of the interrelationships between the structure and function of the large arteries would lead to optimize cardiovascular disease prevention strategies. In this study, we investigated the relationships of aortic arterial stiffness assessed by carotid-femoral pulse-wave velocity (PWV), with carotid plaque echogenicity assessed by B-mode ultrasound. We analyzed 561 subjects (without coronary heart disease or stroke) who were volunteers for free health examinations (age, 58.3+/-10.8 years; 32.6% women). Extracranial carotid plaque echogenicity was graded from 1 (plaque appearing black or almost black) to 4 (plaque appearing white or almost white) according to the Gray-Weale classification. Plaques of grades 1 and 2 were defined as echolucent plaques, and plaques of grades 3 and 4 were defined as echogenic plaques. Fifty-one subjects (9.1%) had echolucent carotid plaques, 109 (19.4%) had echogenic plaques, and 401 (71.5%) had no plaques. Subjects with echogenic plaques had higher PWV mean (12.9+/-2.8 m/s) compared with those without plaques (11.1+/-2.3 m/s, P<0.001) and compared with those with echolucent plaques (11.3+/-2.3 m/s, P<0.01). The PWV means in subjects without plaques and those with echolucent plaques were similar and not statistically different (P=0.55). When multivariate adjustment for major known cardiovascular risk factors was performed, these results were not markedly modified. Similar patterns of results were also observed in many subgroups according to age, gender, and hypertensive status. This study provides the first evidence that echogenic but not echolucent carotid plaques are associated with aortic arterial stiffness. This association applies to individuals with normal blood pressure and those with elevated blood pressure. Assessment of the joint and interaction effects of plaque morphology and arterial stiffness on the occurrence of cardiovascular events would permit a better identification of high-risk subjects. PMID:12623953

  19. Low Copper and High Manganese Levels in Prion Protein Plaques

    PubMed Central

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecht, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; Aiken, Judd M.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system. PMID:23435237

  20. Laser speckle imaging of atherosclerotic plaques through optical fiber bundles.

    PubMed

    Nadkarni, Seemantini K; Bouma, Brett E; Yelin, Dvir; Gulati, Amneet; Tearney, Guillermo J

    2008-01-01

    Laser speckle imaging (LSI), a new technique that measures an index of plaque viscoelasticity, has been investigated recently to characterize atherosclerotic plaques. These prior studies demonstrated the diagnostic potential of LSI for detecting high-risk plaques and were conducted ex vivo. To conduct intracoronary LSI in vivo, the laser speckle pattern must be transmitted from the coronary wall to the image detector in the presence of cardiac motion. Small-diameter, flexible optical fiber bundles, similar to those used in coronary angioscopy, may be incorporated into an intravascular catheter for this purpose. A key challenge is that laser speckle is influenced by inter-fiber leakage of light, which may be exacerbated during bundle motion. In this study, we tested the capability of optical fiber bundles to transmit laser speckle patterns obtained from atherosclerotic plaques and evaluated the influence of motion on the diagnostic accuracy of fiber bundle-based LSI. Time-varying helium-neon laser speckle images of aortic plaques were obtained while cyclically moving the flexible length of the bundle to mimic coronary motion. Our results show that leached fiber bundles may reliably transmit laser speckle images in the presence of cardiac motion, providing a viable option to conduct intracoronary LSI. PMID:19021396

  1. Low copper and high manganese levels in prion protein plaques

    USGS Publications Warehouse

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

  2. Update on the role of neutrophils in atherosclerotic plaque vulnerability.

    PubMed

    Carbone, Federico; Mach, Francois; Montecucco, Fabrizio

    2015-01-01

    Atherosclerosis is the main pathophysiological process underlying acute cardiovascular diseases. Life-threatening conditions, such as myocardial infarction and ischemic stroke, are provoked by the sudden rupture of vulnerable atherosclerotic plaques, characterized by thin, highly inflamed and collagen-poor fibrous cap. Whereas both innate and adaptive inflammation progressively emerged as driving force of this processes, less is known about the involvement of neutrophils (PMNs). Advances in laboratory techniques during the last two decades disclosed that PMNs play a crucial role in promoting plaque vulnerability by the release of different enzymes, such as gelatinases (matrix metalloproteinases) collagenases, elastase and myeloperoxidase. Accordingly, circulating levels of PMNs and their products have been investigated as potential markers of plaque instability in both primary and secondary prevention on cardiovascular diseases. In addition, the development of different classes of drugs targeting PMNs activation is emerging as an interesting field of research. This narrative review will provide an update on the role of PMNs in promoting plaque vulnerability also discussing the potential effects of therapeutic strategies targeting PMN on plaque vulnerability. PMID:25382205

  3. Plaque-like dermatofibroma: A distinct and rare benign neoplasm?

    PubMed

    Leow, Liang Joo; Sinclair, Peter A; Horton, Jeremy J

    2008-05-01

    Unusual large dermatofibromata are reported in a 40-year-old man and a 48-year-old man, who both presented with plaques on a lower limb. The largest plaque in each case was well-defined, reddish brown, indurated and measured 50 mm x 30 mm and 70 mm x 40 mm, respectively. Several satellite lesions were present around the large plaques. Dermoscopic examination showed diffuse homogenous pigmentation in the absence of other diagnostic criteria for dermatofibroma. Light microscopy of biopsies from each patient displayed similar features. There was a dermal proliferation of fibrohistiocytic cells that entrapped intervening thickened collagen fibres. The overlying epidermis was acanthotic, and in some instances this showed basal hyperpigmentation. There was no evidence of malignancy. Immunohistochemical staining was positive for Factor XIIIa and negative for CD34. Based on the histological findings, a diagnosis of dermatofibroma was made for each of these cases. Fewer than 20 adult cases of large dermatofibroma of this scale, designated giant dermatofibroma, have been reported to date; and only two have shown a plaque-like appearance, the remainder being pedunculated. The authors propose plaque-like dermatofibroma as a variety of large dermatofibroma distinct to pedunculated giant dermatofibroma. PMID:18412813

  4. Non-invasive molecular imaging of vulnerable atherosclerotic plaques.

    PubMed

    Magnoni, Marco; Ammirati, Enrico; Camici, Paolo G

    2015-04-01

    The growing discoveries coming from clinical and basic research during the past decades have revolutionized our knowledge regarding pathophysiologic mechanisms underlying the atherosclerotic process and its thrombotic complications. The traditional view focusing on the severity of stenosis of atherosclerotic plaque has given way to the evidence that the clinical complications of atherosclerotic vascular disease, particularly the propensity to develop thrombotic complications, are determined mainly by the biological composition of the plaque. This paradigm shift has reinforced the need to move from the sole anatomical assessment toward combined anatomic and functional imaging modalities enabling the molecular and cellular characterization of the disease on top of its structural properties. Together, the progress to identify molecular targets related to plaque vulnerability and the improvement of imaging techniques for the detection of such molecular targets have allowed us to obtain new important pathophysiological information. This might allow better patient stratification for the identification of subjects at high risk to develop premature atherosclerosis who might need an aggressive therapeutic approach. Nuclear techniques, magnetic resonance imaging, computed tomography angiography, and contrast-enhanced ultrasound represent the currently available non-invasive imaging modalities for molecular imaging which can provide different and complementary insights into the biological features of the atherosclerotic process. This clinical review will discuss the evidence and potential translational applications of the individual imaging techniques particularly concerning their ability to detect the main atherosclerotic features related to plaque vulnerability, such as plaque inflammation and intertwined neovascularization. PMID:25702846

  5. Iron in arterial plaque: modifiable risk factor for atherosclerosis.

    PubMed

    Sullivan, Jerome L

    2009-07-01

    It has been proposed that iron depletion protects against cardiovascular disease. There is increasing evidence that one mechanism for this protection may involve a reduction in iron levels within atherosclerotic plaque. Large increases in iron concentration are seen in human atherosclerotic lesions in comparison to levels in healthy arterial tissue. In animal models, depletion of lesion iron levels in vivo by phlebotomy, systemic iron chelation treatment or dietary iron restriction reduces lesion size and/or increases plaque stability. A number of factors associated with increased arterial disease or increased cardiovascular events is also associated with increased plaque iron. In rats, infusion of angiotensin II increases ferritin levels and arterial thickness which are reversed by treatment with the iron chelator deferoxamine. In humans, a polymorphism for haptoglobin associated with increased cardiovascular disease is also characterized by increased lesional iron. Heme oxygenase 1 (HO1) is an important component of the system for mobilization of iron from macrophages. Human HO1 promoter polymorphisms causing weaker upregulation of the enzyme are associated with increased cardiovascular disease and increased serum ferritin. Increased cardiovascular disease associated with inflammation may be in part caused by elevated hepcidin levels that promote retention of iron within plaque macrophages. Defective retention of iron within arterial macrophages in genetic hemochromatosis may explain why there is little evidence of increased atherosclerosis in this disorder despite systemic iron overload. The reviewed findings support the concept that arterial plaque iron is a modifiable risk factor for atherogenesis. PMID:18619522

  6. Contrast-enhanced ultrasound imaging of the vasa vasorum of carotid artery plaque

    PubMed Central

    Song, Ze-Zhou; Zhang, Yan-Ming

    2015-01-01

    The vasa vasorum of carotid artery plaque is a novel marker of accurately evaluating the vulnerability of carotid artery plaque, which was associated with symptomatic cerebrovascular and cardiovascular disease. The presence of ultrasound contrast agents in carotid artery plaque represents the presence of the vasa vasorum in carotid artery plaque because the ultrasound contrast agents are strict intravascular tracers. Therefore, contrast-enhanced ultrasound (CEUS) is a novel and safe imaging modality for evaluating the vasa vasorum in carotid artery plaque. However, there are some issues that needs to be assessed to embody fully the clinical utility of the vasa vasorum in carotid artery plaque with CEUS. PMID:26120382

  7. An integrated system for the segmentation of atherosclerotic carotid plaque.

    PubMed

    Loizou, Christos P; Pattichis, Constantinos S; Pantziaris, Marios; Nicolaides, Andrew

    2007-11-01

    In this paper, we propose and evaluate an integrated system for the segmentation of atherosclerotic plaque in ultrasound imaging of the carotid artery based on normalization, speckle reduction filtering, and four different snakes segmentation methods. These methods are the Williams and Shah, Balloon, Lai and Chin, and the gradient vector flow (GVF) snake. The performance of the four different plaque snakes segmentation methods was tested on 80 longitudinal ultrasound images of the carotid artery using receiver operating characteristic (ROC) analysis and the manual delineations of an expert. All four methods were very satisfactory and similar in all measures evaluated, with no significant differences between them; however, the Lai and Chin snakes segmentation method gave slightly better results. Concluding, it is proposed that the integrated system investigated in this study could be used successfully for the automated segmentation of the carotid plaque. PMID:18046941

  8. Frequency and healing of nonculprit coronary artery plaque disruptions in patients with acute myocardial infarction.

    PubMed

    Okada, Katsuki; Ueda, Yasunori; Matsuo, Koshi; Nishio, Mayu; Hirata, Akio; Kashiwase, Kazunori; Asai, Mitsutoshi; Nemoto, Takayoshi; Kodama, Kazuhisa

    2011-05-15

    The pathophysiology of plaque disruption and healing in nonculprit segments has not been clarified. Therefore, we investigated the frequency of plaque disruptions in nonculprit segments and whether those plaques are stabilized during follow-ups in patients with acute myocardial infarction (AMI) by serial angioscopic observations. Analyzed were 13 consecutive patients with AMI in whom infarct-related arteries were serially observed by angioscopy immediately after reperfusion and at 1- and 6-month follow-ups. Color of plaques was graded as 0 (white), 1 (slight yellow), 2 (yellow), or 3 (intensive yellow). Plaques with thrombus were defined as disrupted. Although number of nonculprit yellow plaques did not change from immediately after reperfusion to 6 months, the maximum color grade of those plaques and incidence of disrupted plaques in nonculprit segments (immediate vs 1 month vs 6 months 31% vs 8% vs 0%) decreased significantly by 6 months. Plaque stabilization as shown by disappearance of thrombus was significantly associated with plaque regression as shown by a decrease of maximum yellow color grade in nonculprit segments. In conclusion, patients with AMI frequently had disrupted and actively thrombogenic yellow plaques in nonculprit segments of the culprit vessel, and those plaques healed with decreases of yellow color grade and thrombogenicity during 6-months follow-up. Plaque disruption and healing occur not only at the culprit lesion but may be a pan-coronary process in patients with AMI. PMID:21377645

  9. Dosimetric study of the 15 mm ROPES eye plaque

    SciTech Connect

    Granero, D.; Perez-Calatayud, J.; Ballester, F.; Casal, E.; Frutos, J.M. de [Department of Atomic, Molecular and Nuclear Physics and IFIC, University of Valencia-CSIC, Dr. Moliner 50, E46100 Burjassot (Spain); Medical Physics Section, University Hospital, Av. Ramon y Cajal 3, E47011 Valladolid (Spain)

    2004-12-01

    The main aim of this paper is to make a study of dose-rate distributions obtained around the 15 mm, radiation oncology physics and engineering services, Australia (ROPES) eye plaque loaded with {sup 125}I model 6711 radioactive seeds. In this study, we have carried out a comparison of the dose-rate distributions obtained by the algorithm used by the Plaque Simulator (PS) (BEBIG GmbH, Berlin, Germany) treatment planning system with those obtained by means of the Monte Carlo method for the ROPES eye plaque. A simple method to obtain the dose-rate distributions in a treatment planning system via the superposition of the dose-rate distributions of a seed placed in the eye plaque has been developed. The method uses eye plaque located in a simplified geometry of the head anatomy and distributions obtained by means of the Monte Carlo code GEANT4. The favorable results obtained in the development of this method suggest that it could be implemented on a treatment planning system to improve dose-rate calculations. We have also found that the dose-rate falls sharply along the eye and that outside the eye the dose-rate is very low. Furthermore, the lack of backscatter photons from the air located outside the eye-head phantom produces a dose reduction negligible for distances from the eye-plaque r<1 cm but reaches up to 20% near the air-eye interface. Results showed that the treatment planning system lacks accuracy around the border of the eye (in the sclera and the surrounding area) due to the simplicity of the algorithm used. The BEBIG treatment planning system uses a global attenuation factor that takes into account the effect of the eye plaque seed carrier and the lack of backscatter photons caused by the metallic cover, which in the case of a ROPES eye plaque has a default value of T=1 (no correction). In the present study, a global attenuation factor T=0.96 and an air-interface correction factor which improve on treatment planning system calculations were obtained.

  10. Dosimetric study of the 15 mm ROPES eye plaque.

    PubMed

    Granero, D; Pérez-Calatayud, J; Ballester, F; Casal, E; de Frutos, J M

    2004-12-01

    The main aim of this paper is to make a study of dose-rate distributions obtained around the 15 mm, radiation oncology physics and engineering services, Australia (ROPES) eye plaque loaded with 125I model 6711 radioactive seeds. In this study, we have carried out a comparison of the dose-rate distributions obtained by the algorithm used by the Plaque Simulator (PS) (BEBIG GmbH, Berlin, Germany) treatment planning system with those obtained by means of the Monte Carlo method for the ROPES eye plaque. A simple method to obtain the dose-rate distributions in a treatment planning system via the superposition of the dose-rate distributions of a seed placed in the eye plaque has been developed. The method uses eye plaque located in a simplified geometry of the head anatomy and distributions obtained by means of the Monte Carlo code GEANT4. The favorable results obtained in the development of this method suggest that it could be implemented on a treatment planning system to improve dose-rate calculations. We have also found that the dose-rate falls sharply along the eye and that outside the eye the dose-rate is very low. Furthermore, the lack of backscatter photons from the air located outside the eye-head phantom produces a dose reduction negligible for distances from the eye-plaque r<1 cm but reaches up to 20% near the air-eye interface. Results showed that the treatment planning system lacks accuracy around the border of the eye (in the sclera and the surrounding area) due to the simplicity of the algorithm used. The BEBIG treatment planning system uses a global attenuation factor that takes into account the effect of the eye plaque seed carrier and the lack of backscatter photons caused by the metallic cover, which in the case of a ROPES eye plaque has a default value of T= 1 (no correction). In the present study, a global attenuation factor T=0.96 and an air-interface correction factor which improve on treatment planning system calculations were obtained. PMID:15651616

  11. An assessment of the vulnerability of carotid plaques: a comparative study between intraplaque neovascularization and plaque echogenicity

    PubMed Central

    2013-01-01

    Background Carotid plaque echolucency as detected by Color Doppler ultrasonography (CDUS) has been used as a potential marker of plaque vulnerability. However, contrast-enhanced ultrasound (CEUS) has recently been shown to be a valuable method to evaluate the vulnerability and neovascularization within carotid atherosclerotic plaques. The aim of this study was to compare CEUS and CDUS in the assessment of plaque vulnerability using transcranial color Doppler (TCD) monitoring of microembolic signals (MES) as a reference technique. Methods A total of 46 subjects with arterial stenosis (? 50%) underwent a carotid duplex ultrasound, TCD monitoring of MES and CEUS (SonoVue doses of 2.0 mL) within a span of 3 days. The agreement between the CEUS, CDUS, and MES findings was assessed with a chi-square test. A p-value less than 0.05 was considered statistically significant. Results Neovascularization was observed in 30 lesions (44.4%). The vascular risk factors for stroke were similar and there were no age or gender differences between the 2 groups. Using CEUS, MES were identified in 2 patients (12.5%) within class 1 (non-neovascularization) as opposed to 15 patients (50.0%) within class 2 (neovascularization) (p?=?0.023). CDUS revealed no significant differences in the appearance of the MES between the 2 groups (hyperechoic and hypoechoic) (p?=?0.237). Conclusion This study provides preliminary evidence to suggest that intraplaque neovascularization detected by CEUS is associated with the presence of MESs, where as plaque echogenicity on traditional CDUS does not. These findings argue that CEUS may better identify high-risk plaques. PMID:23537052

  12. 21 CFR 872.5580 - Oral rinse to reduce the adhesion of dental plaque.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...rinse to reduce the adhesion of dental plaque. 872.5580 Section...HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices...rinse to reduce the adhesion of dental plaque. (a)...

  13. 21 CFR 872.5580 - Oral rinse to reduce the adhesion of dental plaque.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...rinse to reduce the adhesion of dental plaque. 872.5580 Section...HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices...rinse to reduce the adhesion of dental plaque. (a)...

  14. 21 CFR 872.5580 - Oral rinse to reduce the adhesion of dental plaque.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...rinse to reduce the adhesion of dental plaque. 872.5580 Section...HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices...rinse to reduce the adhesion of dental plaque. (a)...

  15. 21 CFR 872.5580 - Oral rinse to reduce the adhesion of dental plaque.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...rinse to reduce the adhesion of dental plaque. 872.5580 Section...HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices...rinse to reduce the adhesion of dental plaque. (a)...

  16. 21 CFR 872.5580 - Oral rinse to reduce the adhesion of dental plaque.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...rinse to reduce the adhesion of dental plaque. 872.5580 Section...HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Therapeutic Devices...rinse to reduce the adhesion of dental plaque. (a)...

  17. Multimodal characterization of compositional, structural and functional features of human atherosclerotic plaques

    PubMed Central

    Sun, Yang; Chaudhari, Abhijit J.; Lam, Matthew; Xie, Hongtao; Yankelevich, Diego R.; Phipps, Jennifer; Liu, Jing; Fishbein, Michael C.; Cannata, Jonathan M.; Shung, K. Kirk; Marcu, Laura

    2011-01-01

    Detection of atherosclerotic plaque vulnerability has critical clinical implications for avoiding sudden death in patients with high risk of plaque rupture. We report on multimodality imaging of ex-vivo human carotid plaque samples using a system that integrates fluorescence lifetime imaging (FLIM), ultrasonic backscatter microscopy (UBM), and photoacoustic imaging (PAI). Biochemical composition is differentiated with a high temporal resolution and sensitivity at the surface of the plaque by the FLIM subsystem. 3D microanatomy of the whole plaque is reconstructed by the UBM. Functional imaging associated with optical absorption contrast is evaluated from the PAI component. Simultaneous recordings of the optical, ultrasonic, and photoacoustic data present a wealth of complementary information concerning the plaque composition, structure, and function that are related to plaque vulnerability. This approach is expected to improve our ability to study atherosclerotic plaques. The multimodal system presented here can be translated into a catheter based intraluminal system for future clinical studies. PMID:21833365

  18. Mechanism of ceroid formation in atherosclerotic plaque: in situ studies combination of Raman and fluorescence spectroscopy

    E-print Network

    Haka, Abigail S.

    Accumulation of the lipid-protein complex ceroid is a characteristic of atherosclerotic plaque. The mechanism of ceroid formation has been extensively studied, because the complex is postulated to contribute to plaque ...

  19. Plaque: What It Is and How to Get Rid of It

    MedlinePLUS

    ... for a fresh feeling! Rinse again. Remember: Food residues, especially sweets, provide nutrients for the germs that ... why it is important to remove all food residues, as well as plaque, from teeth. Remove plaque ...

  20. Modelling of fluid structure interactions in stenosed arteries: effect of plaque deformability

    E-print Network

    Paris-Sud XI, Université de

    Modelling of fluid structure interactions in stenosed arteries: effect of plaque deformability of fluid structure interactions in stenosed arteries. Stenoses in arteries are usually induced the mechanical response of plaques in the arteries [1]. This mechanical response is mainly induced

  1. Plaque-Type Blue Nevus of the Oral Cavity

    Microsoft Academic Search

    Susanna K. Fistarol; Peter H. Itin

    2005-01-01

    Background: The blue nevus of the oral cavity is a rare lesion with important differential diagnoses. The plaque-type blue nevus is an uncommon variant of the blue nevus. Because of its particular clinical appearance, it can easily be confused with satellite metastases from malignant melanoma. The diagnosis usually requires a biopsy. Objectives: To describe the clinical and histological features of

  2. Manufacturer's plaque located on north side of south parapet wall, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Manufacturer's plaque located on north side of south parapet wall, bridge over little Pince Creek (S.R. 1026, section 002), looking south - Bridge over Little Pine Creek, State Route 1026 over Little Pine Creek, 2.01 kilometers (1.25 miles) East of Bendertown, Jonestown, Columbia County, PA

  3. Aminomalonic Acid: Identification in Escherichia coli and Atherosclerotic Plaque

    Microsoft Academic Search

    John J. van Buskirk; Wolff M. Kirsch; Don L. Kleyer; Robert M. Barkley; Tad H. Koch

    1984-01-01

    Aminomalonic acid (Ama) has been isolated from proteins of Escherichia coli and human atherosclerotic plaque. The presence of Ama has important biological implications because the malonic acid moiety potentially imparts calcium binding properties to protein. Ama was obtained by anaerobic alkaline hydrolysis and identified by chromatographic behavior, quantitative acid-mediated decarboxylation to glycine, and unambiguous gas chromatographic\\/mass spectral detection. The chromatographic,

  4. Fermentation of five sucrose isomers by human dental plaque bacteria.

    PubMed

    Matsuyama, J; Sato, T; Hoshino, E; Noda, T; Takahashi, N

    2003-01-01

    Sucrose has five structural isomers: palatinose, trehalulose, turanose, maltulose and leucrose. Although these isomers have been reported to be noncariogenic disaccharides, which cannot be utilized by mutans streptococci, there is no information about their fermentability by other bacteria in dental plaque. The purpose of the present study was to examine whether these isomers were fermented by predominant bacteria in human dental plaque. Clinical bacterial isolates obtained from dental plaque from 3 children aged 22 months to 50 months (146 strains) were inoculated into 3 ml of peptone-yeast extract (PY medium) containing glucose for 1 day, then an aliquot of 20 microl of culture medium was inoculated into 1 ml of PY medium containing 1% (w/v) of the respective test carbohydrates. After incubation for 1 day, the pH values and the optical density at 660 nm of the cultures were measured. Fermentation ability was measured by pH or=0.5. Of the clinical isolates, 33% fermented palatinose, and 69% of these were Actinomyces species. All of the palatinose-fermenting bacterial strains fermented trehalulose, 25% fermented turanose, 70% fermented maltulose and 23% fermented leucrose. We therefore conclude that, in human dental plaque, there are significant numbers of bacteria that are able to ferment sucrose isomers. PMID:14571118

  5. Plaque Formation in Agar by Single Antibody-Producing Cells

    Microsoft Academic Search

    Niels K. Jerne; Albert A. Nordin

    1963-01-01

    Distinct plaques, each of which is due to the release of hemolysin by a single antibody-forming cell, are revealed by complement after incubation, in an agar layer, of a mixture of sheep red cells and lymphoid cells from a rabbit immunized with sheep red cells.

  6. Intravascular palpography for high-risk vulnerable plaque assessment

    Microsoft Academic Search

    Johannes A. Schaar; Korte de C. L; Frits Mastik; Radj Baldewsing; Evelyn Regar; Steen van der A. F. W; P. W. J. C. Serruys; Feyter de P. J; C. J. Slager

    2003-01-01

    Background: The composition of an atherosclerotic plaque is considered more important than the degree of stenosis. An unstable lesion may rupture and cause an acute thrombotic reaction. Most of these lesions contain a large lipid pool cov- ered by an inflamed thin fibrous cap. The stress in the cap in- creases with decreasing cap thickness and increasing macrophage infiltration. Intravascular

  7. Variogram methods for texture classification of atherosclerotic plaque ultrasound images

    NASA Astrophysics Data System (ADS)

    Jeromin, Oliver M.; Pattichis, Marios S.; Pattichis, Constantinos; Kyriacou, Efthyvoulos; Nicolaides, Andrew

    2006-03-01

    Stroke is the third leading cause of death in the western world and the major cause of disability in adults. The type and stenosis of extracranial carotid artery disease is often responsible for ischemic strokes, transient ischemic attacks (TIAs) or amaurosis fugax (AF). The identification and grading of stenosis can be done using gray scale ultrasound scans. The appearance of B-scan pictures containing various granular structures makes the use of texture analysis techniques suitable for computer assisted tissue characterization purposes. The objective of this study is to investigate the usefulness of variogram analysis in the assessment of ultrasound plague morphology. The variogram estimates the variance of random fields, from arbitrary samples in space. We explore stationary random field models based on the variogram, which can be applied in ultrasound plaque imaging leading to a Computer Aided Diagnosis (CAD) system for the early detection of symptomatic atherosclerotic plaques. Non-parametric tests on the variogram coefficients show that the cofficients coming from symptomatic versus asymptomatic plaques come from distinct distributions. Furthermore, we show significant improvement in class separation, when a log point-transformation is applied to the images, prior to variogram estimation. Model fitting using least squares is explored for anisotropic variograms along specific directions. Comparative classification results, show that variogram coefficients can be used for the early detection of symptomatic cases, and also exhibit the largest class distances between symptomatic and asymptomatic plaque images, as compared to over 60 other texture features, used in the literature.

  8. 4. VISTA POINT AND INTERPRETIVE PLAQUE AT LEE VINING CANYON. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VISTA POINT AND INTERPRETIVE PLAQUE AT LEE VINING CANYON. NOTE ROAD CUT ON CANYON WALL. LOOKING NNE. GIS: N-37 56 30.3 / 119 13 44.8 - Tioga Road, Between Crane Flat & Tioga Pass, Yosemite Village, Mariposa County, CA

  9. [Optimization of black blood CINE for mobile plaque].

    PubMed

    Nakagawa, Kenichi; Komaki, Shinsuke

    2013-11-01

    For examining carotid plaque, black blood (BB) magnetic resonance (MR) imaging can diagnose plaque components based on MR signals. Dynamic images for evaluating the mobility of carotid plaque may also be useful as an adjunct to the diagnosis of carotid plaque. The aim of this study was to find optimal parameters for dynamic images using the black blood technique (BB CINE). All experiments were acquired using electrocardiographically (ECG)-gated T1 turbo field echo (T1 TFE) combined with the regional saturation technique (REST) and improved motion-sensitized driven equilibrium (iMSDE) at 1.5 tesla (T). The following parameters were investigated. (1) Four fat suppression techniques: spectral presaturation with IR (SPIR), the principle of selective excitation technique (PROSET) with a binomial excitation of 1-1 (PROSET1-1), PROSET1-2-1 and PROSET1-3-3-1; (2) TFE factors 1 and 2; and (3) flow velocity encoding (venc) of 1, 3, 5, 10 and 15 cm/s for iMSDE. The results showed the optimal parameters for BB CINE to be PROSET1-2-1, TFE factor 2, and flow venc of 3-5 cm/s for iMSDE. PMID:24256651

  10. Secretory group II phospholipase A2 in human atherosclerotic plaques

    Microsoft Academic Search

    Mario Menschikowski; Michael Kasper; Peter Lattke; Andrea Schiering; Sigbert Schiefer; Hubertus Stockinger; Werner Jaross

    1995-01-01

    Atherosclerotic plaques exhibit a series of features that are similar to those of chronic inflammation. Based on the fact that during inflammation several cell types synthesize and secrete a group II phospholipase A2 (PLA2), an immunohistochemical study was undertaken to explore whether this enzyme can be identified in human atherosclerotic lesions. Tissue specimens obtained from 13 patients who had undergone

  11. Atherothrombosis and Plaque Heterology: Different Location or a Unique Disease?

    Microsoft Academic Search

    M. Slevin; Q. Wang; A. Luque; Oriol Juan-Babot; J. Gaffney; P. Kumar; S. Kumar; L. Badimon; J. Krupinski

    2008-01-01

    Formation of unstable plaques frequently results in atherothrombosis, the major cause for ischaemic stroke, myocardial infarction and peripheral arterial disease. Patients who have symptomatic thrombosis in one vascular bed are at increased risk of disease in other beds. However, the development of the disease in carotid, coronary and peripheral arteries may have different pathophysiology suggesting that more complex treatment protocols

  12. Atherosclerotic Plaque at the Carotid Bifurcation: CT Angiographic Appearance with Histopathologic Correlation

    Microsoft Academic Search

    T. Barry Oliver; G. Alistair Lammie; Andrew R. Wright; Joanna Wardlaw; Sandi G. Patel; Russell Peek; C. Vaughan Ruckley; Donald A. Collie

    BACKGROUND AND PURPOSE:The likelihood that carotid plaque will give rise to cerebral ischemia probably relates to the degree of arterial stenosis and to plaque morphology. The aim of this study was to assess whether features seen at CT angiography might be used to predict carotid plaque stability by comparing CT angiograms with histopathologic examinations of the carotid artery bifurcation. METHODS:

  13. Lipid composition in atheromatous plaque: evaluation of the lipid three-phase percentage

    Microsoft Academic Search

    Enrico Marinello; Carlo Setacci; Michele Giubbolini; Giuliano Cinci; Barbara Frosi; Brunetta Porcelli; Lucia Terzuoli

    2003-01-01

    There is a renewed interest in the study of plaque lipid composition because it is recognized that it, rather than the luminal narrowing, influences the plaque stability and determines patient symptoms.At this purpose, we quantitatively evaluated in the carotid plaque of different categories of patients the expression of triglycerides, phospholipids, cholesterol, free cholesterol, esters of cholesterol, and the percentages of

  14. The role of shear stress in the destabilization of vulnerable plaques and related therapeutic implications

    Microsoft Academic Search

    JJ Wentzel; FJH Gijsen; A Thury; AC van der Wal; JA Schaar; PW Serruys; CJ Slager

    2005-01-01

    American Heart Association type IV plaques consist of a lipid core covered by a fibrous cap, and develop at locations of eccentric low shear stress. Vascular remodeling initially preserves the lumen diameter while maintaining the low shear stress conditions that encourage plaque growth. When these plaques eventually start to intrude into the lumen, the shear stress in the area surrounding

  15. The Impact of Calcification on the Biomechanical Stability of Atherosclerotic Plaques

    Microsoft Academic Search

    Hayden Huang; Renu Virmani; Hesham Younis; Allen P. Burke; Roger D. Kamm; Richard T. Lee

    2001-01-01

    Background—Increased biomechanical stresses in the fibrous cap of atherosclerotic plaques contribute to plaque rupture and, consequently, to thrombosis and myocardial infarction. Thin fibrous caps and large lipid pools are important determinants of increased plaque stresses. Although coronary calcification is associated with worse cardiovascular prognosis, the relationship between atheroma calcification and stresses is incompletely described. Methods and Results—To test the hypothesis

  16. Electron Microscopic Study of the Effect of Water Jet Lavage Devices on Dental Plaque

    Microsoft Academic Search

    John M. Brady; Walter A. Gray; Surindar N. Bhaskar

    1973-01-01

    The maxillary posterior teeth of nine rhesus monkeys were treated with a pulsating water lavage instrument at 70 psi (high setting). Electron microscopic studies of pre- and post-lavage plaque samples showed that water jet devices as used in this experiment either removed the plaque completely or caused irreversible damage to the microbial forms in the plaque matrix.

  17. Development of Positron Emission Tomography ?-Amyloid Plaque Imaging Agents

    PubMed Central

    Mathis, Chester A.; Mason, N. Scott; Lopresti, Brian J.; Klunk, William E.

    2012-01-01

    For 100 years, ?-amyloid (A?) plaques and neurofibrillary tangles (NFTs) have been recognized as the neuropathological hallmarks of Alzheimer’s disease (AD), and their presence or absence could only be assessed postmortem using stains and dyes that identified these microscopic structures. Approximately 10 years ago, the first successful A? plaque–specific positron emission tomography (PET) imaging study was conducted in a living human subject clinically diagnosed with probable AD using the 11C-labeled radiopharmaceutical Pittsburgh Compound B (PiB). Laboratory studies and preclinical evaluations to design PiB began a decade earlier than the first human PiB PET study and involved chemical modifications of different well-known dyes that bound specifically to the extended ?-pleated sheets that comprise the fibrils of amyloid proteins such as A? plaques, NFTs, ?-synuclein deposits, and prions. These preclinical studies were conducted in our laboratories at the University of Pittsburgh, starting with Congo red derivatives, followed by Chrysamine G derivatives, followed by X-series compounds, and finally with neutral derivatives of thioflavin-T. The in vitro and in vivo evaluations of the different derivatives as candidate PET radioligands for imaging A? plaques and neurofibrillary tangles in human brain are described in this review, along with the specific evaluation criteria by which the candidate radioligands were judged. Out of these studies came PiB, a PET radioligand that binds selectively and with high affinity to only fibrillar forms of A?. PiB has been used in many different human research protocols throughout the world and has demonstrated the usefulness of assessing the A? plaque status of subjects many years before the clinical diagnosis of probable AD. Recently, longer-lived 18F-radiolabeled A?-selective radiopharmaceuticals have been developed. It is likely that the full clinical impact of these imaging agents will be realized by identifying presymptomatic subjects who would benefit from early drug treatments with future disease-modifying AD therapeutics. PMID:23026364

  18. Optical Coherence Tomography Analysis of Attenuated Plaques Detected by Intravascular Ultrasound in Patients with Acute Coronary Syndromes

    PubMed Central

    Kubo, Takashi; Matsuo, Yoshiki; Ino, Yasushi; Tanimoto, Takashi; Ishibashi, Kohei; Komukai, Kenichi; Kitabata, Hironori; Tanaka, Atsushi; Kimura, Keizo; Imanishi, Toshio; Akasaka, Takashi

    2011-01-01

    Background. Recent intravascular ultrasound (IVUS) studies have demonstrated that hypoechoic plaque with deep ultrasound attenuation despite absence of bright calcium is common in acute coronary syndrome. Such “attenuated plaque” may be an IVUS characteristic of unstable lesion. Methods. We used optical coherence tomography (OCT) in 104 patients with unstable angina to compare lesion characteristics between IVUS-detected attenuated plaque and nonattenuated plaque. Results. IVUS-detected attenuated plaque was observed in 41 (39%) patients. OCT-detected lipidic plaque (88% versus 49%, P < 0.001), thin-cap fibroatheroma (48% versus 16%, P < 0.001), plaque rupture (44% versus 11%, P < 0.001), and intracoronary thrombus (54% versus 17%, P < 0.001) were more often seen in IVUS-detected attenuated plaques compared with nonattenuated plaques. Conclusions. IVUS-detected attenuated plaque has many characteristics of unstable coronary lesion. The presence of attended plaque might be an important marker of lesion instability. PMID:21941667

  19. Magnetic resonance imaging of amyloid plaques in transgenic mouse models of Alzheimer's disease

    PubMed Central

    Chamberlain, Ryan; Wengenack, Thomas M.; Poduslo, Joseph F.; Garwood, Michael; Jack, Clifford R.

    2011-01-01

    A major objective in the treatment of Alzheimer's disease is amyloid plaque reduction. Transgenic mouse models of Alzheimer's disease provide a controlled and consistent environment for studying amyloid plaque deposition in Alzheimer's disease. Magnetic resonance imaging is an attractive tool for longitudinal studies because it offers non-invasive monitoring of amyloid plaques. Recent studies have demonstrated the ability of magnetic resonance imaging to detect individual plaques in living mice. This review discusses the mouse models, MR pulse sequences, and parameters that have been used to image plaques and how they can be optimized for future studies. PMID:21499442

  20. Patient-specific prediction of coronary plaque growth from CTA angiography: a multiscale model for plaque formation and progression.

    PubMed

    Parodi, Oberdan; Exarchos, Themis P; Marraccini, Paolo; Vozzi, Federico; Milosevic, Zarko; Nikolic, Dalibor; Sakellarios, Antonis; Siogkas, Panagiotis K; Fotiadis, Dimitrios I; Filipovic, Nenad

    2012-09-01

    Computational fluid dynamics methods based on in vivo 3-D vessel reconstructions have recently been identified the influence of wall shear stress on endothelial cells as well as on vascular smooth muscle cells, resulting in different events such as flow mediated vasodilatation, atherosclerosis, and vascular remodeling. Development of image-based modeling technologies for simulating patient-specific local blood flows is introducing a novel approach to risk prediction for coronary plaque growth and progression. In this study, we developed 3-D model of plaque formation and progression that was tested in a set of patients who underwent coronary computed tomography angiography (CTA) for anginal symptoms. The 3-D blood flow is described by the Navier-Stokes equations, together with the continuity equation. Mass transfer within the blood lumen and through the arterial wall is coupled with the blood flow and is modeled by a convection-diffusion equation. The low density lipoprotein (LDL) transports in lumen of the vessel and through the vessel tissue (which has a mass consumption term) are coupled by Kedem-Katchalsky equations. The inflammatory process is modeled using three additional reaction-diffusion partial differential equations. A full 3-D model was created. It includes blood flow and LDL concentration, as well as plaque formation and progression. Furthermore, features potentially affecting plaque growth, such as patient risk score, circulating biomarkers, localization and composition of the initial plaque, and coronary vasodilating capability were also investigated. The proof of concept of the model effectiveness was assessed by repetition of CTA, six months after. PMID:22665513

  1. Plaque Rupture Complications in Murine Atherosclerotic Vein Grafts Can Be Prevented by TIMP-1 Overexpression

    PubMed Central

    de Vries, Margreet R.; Niessen, Hans W. M.; Löwik, Clemens W. G. M.; Hamming, Jaap F.; Jukema, J. Wouter; Quax, Paul H. A.

    2012-01-01

    The current study describes the incidence and phenotype of plaque rupture complications in murine vein grafts. Since matrix metalloproteinases (MMPs) are highly involved in atherosclerotic plaque vulnerability and plaque rupture, we hypothesized that this model can be validated by overexpression of the MMP inhibitor TIMP-1. First we studied 47 vein grafts in hypercholesterolemic ApoE3*Leiden mice for the incidence of plaque complications. In 79% of these grafts, extensive lesions with plaque rupture complications like dissections, intraplaque hemorrhages or erosions with intramural thrombi were found. Next, in vivo Near-InfraRed-Fluorescence imaging demonstrated that electroporation mediated TIMP-1-overexpression reduced local MMP activity in vein grafts by 73% (p<0.01). This led to a 40% reduction in lesion-size after 28d (p?=?0.01) and a more stable lesion phenotype with significant more smooth muscle cells (135%), collagen (47%) and significant less macrophages (44%) and fibrin (55%) than controls. More importantly, lesions in the TIMP-1 group showed a 90% reduction of plaque complications (10/18 of control mice showed plaque complications versus 1/18 in TIMP-1 treated mice). Murine vein grafts are a relevant spontaneous model to study plaque stability and subsequent hemorrhagic complications, resulting in plaque instability. Moreover, inhibition of MMPs by TIMP-1-overexpression resulted in decreased plaque progression, increased stabilization and decreased plaque rupture complications in murine vein grafts. PMID:23071737

  2. Dynamic variations in the ultrasound greyscale median of carotid artery plaques

    PubMed Central

    2013-01-01

    Background Several studies have found that the ultrasound greyscale median (GSM) of carotid artery plaques may be useful for predicting the risk of cerebrovascular events. However, measurements of GSM are typically performed on still ultrasound images ignoring any variations that may be observed on a frame-by-frame basis. The aim of this study was to establish the existence and investigate the nature and extent of these variations. Methods Employing a novel method that enabled plaque boundaries to be tracked semi-automatically, variations in the plaque GSM and observed cross-sectional area were measured for 27 carotid artery plaques (19 consecutive patients, stenosis range 10%-80%) over image sequences of up to 10 seconds in length acquired with a mean frame rate of 32 frames per second. Results Our results showed a mean inter-frame coefficient of variation (CV) of 5.2% (s.d. 2.5%) for GSM and 4.2% (s.d. 2.9%) for the plaque area. Thirteen of the 27 plaques (48%) exhibited CV in GSM greater than 5% whereas only six plaques (22%) had CV in plaque area of greater than 5%. There was no significant correlation between the CV of GSM and plaque area. Conclusions Inter-frame variations in the plaque GSM such as those found in this study have implications on the reproducibility of GSM measurements and their clinical utility. Studies assessing the GSM of carotid artery plaques should consider these variations. PMID:23767988

  3. Pleural plaques: a review of diagnostic issues and possible nonasbestos factors.

    PubMed

    Clarke, Chester C; Mowat, Fionna S; Kelsh, Michael A; Roberts, Mark A

    2006-01-01

    The authors reviewed nonasbestos etiologies and diagnostic issues related to pleural plaques. Through searches of PUBMED and DIALOG using the term pleural plaques, they identified 125 articles. The authors found additional references by reviewing citations of these 125 articles. Exposure to nonasbestos agents (eg, erionite, silicates, manmade fibers) was cited as a possible factor in plaque development, although this association was based on limited data; empyema, tuberculosis, rib fractures, and hemothorax also were cited as potential etiologies. Rib companion shadows, fat, intercostal vessels, and muscles can appear as plaques; thus, radiographic diagnosis requires careful evaluation. Chest x-rays show large false negative and varying false positive rates. The terms calcification and thickening often were used as synonymous with plaques; however, these terms have different meanings. The authors concluded that plaques may be associated with nonasbestos exposures and certain medical conditions. Without a thorough exposure/medical history, plaque reports can be misleading. PMID:17867573

  4. Evaluation of collagen in atherosclerotic plaques: the use of two coherent laser-based imaging methods

    PubMed Central

    Nadkarni, Seemantini K.; Bouma, Brett E.; de Boer, Johannes; Tearney, Guillermo J.

    2009-01-01

    Acute coronary events such as myocardial infarction are frequently caused by the rupture of unstable atherosclerotic plaque. Collagen plays a key role in determining plaque stability. Methods to measure plaque collagen content are invaluable in detecting unstable atherosclerotic plaques. Recently, novel coherent laser-based imaging techniques, such as polarization-sensitive optical coherence tomography (PSOCT) and laser speckle imaging (LSI) have been investigated, and they provide a wealth of information related to collagen content and plaque stability. Additionally, given their potential for intravascular use, these technologies will be invaluable for improving our understanding of the natural history of plaque development and rupture and, hence, enable the detection of unstable plaques. In this article we review recent developments in these techniques and potential challenges in translating these methods into intra-arterial use in patients. PMID:18386093

  5. Ultrasound speckle tracking strain estimation of in vivo carotid artery plaque with in vitro sonomicrometry validation.

    PubMed

    Widman, Erik; Caidahl, Kenneth; Heyde, Brecht; D'hooge, Jan; Larsson, Matilda

    2015-01-01

    Our objective was to validate a previously developed speckle tracking (ST) algorithm to assess strain in common carotid artery plaques. Radial and longitudinal strain was measured in common carotid artery gel phantoms with a plaque-mimicking inclusion using an in-house ST algorithm and sonomicrometry. Moreover, plaque strain by ST for seven patients (77 ± 6 y) with carotid atherosclerosis was compared with a quantitative visual assessment by two experienced physicians. In vitro, good correlation existed between ST and sonomicrometry peak strains, both radially (r = 0.96, p < 0.001) and longitudinally (r = 0.75, p < 0.01). In vivo, greater pulse pressure-adjusted radial and longitudinal strains were found in echolucent plaques than in echogenic plaques. This illustrates the feasibility of ultrasound ST strain estimation in plaques and the possibility of characterizing plaques using ST strain in vivo. PMID:25308946

  6. A comparison of human dental plaque microcosm biofilms grown in an undefined medium and a chemically defined artificial saliva

    Microsoft Academic Search

    L. Wong; C. H. Sissions

    2001-01-01

    The growth and pathogenic properties of dental plaque result from interactions between the microbiota and the oral environment and have been studied in laboratory experimental systems ranging from single or a few species (such as in chemostats) to dental plaque microcosms. Microcosm plaque is an in vitro version of natural plaque and has been explored as a microflora model because

  7. Active and Inactive Edges of Psoriatic Plaques: Identification by Tracing and Investigation by Laser-Doppler Flowmetry and Immunocytochemical Techniques

    Microsoft Academic Search

    Susan Macdonald Hull; Mark Goodfield; Edward John Wood; D. Phil; William John Cunliffe

    1989-01-01

    In plaque psoriasis it is likely that biochemical and ultrastructural changes precede the appearance of the typical plaque that is recognizable clinically. Currently, no technique exists by which the very early changes in psoriasis can be investigated. We report a method in which plaques of psoriasis are serially traced to identify their advancing edge. Eighty-two untreated plaques from 15 patients

  8. Microbiologic aspects of dental plaque and dental caries.

    PubMed

    Marsh, P D

    1999-10-01

    Dental plaque is an example of a microbial biofilm with a diverse microbial composition; it is found naturally on teeth and confers advantages to the host, for example, by preventing colonization by exogenous, and often pathogenic, micro-organisms. In individuals with a high frequency sugar diet, or with a severely compromised saliva flow, the levels of potentially cariogenic bacteria (acid-producing and acid-tolerating species) can increase beyond those compatible with enamel health. This article discusses antimicrobial strategies to control dental caries, including; reducing plaque levels, in general or specific cariogenic bacteria in particular, by antiplaque or antimicrobial agents; reducing bacterial acid production by replacing fermentable carbohydrates in the diet with sugar substitutes, or by interfering with bacterial metabolism with fluoride or antimicrobial agents. PMID:10553246

  9. Apollo 11 Commander Armstrong Presents President With Commemorative Plaque

    NASA Technical Reports Server (NTRS)

    1974-01-01

    On June 4, 1974, 5 years after the successful Apollo 11 lunar landing mission, commander Neil Armstrong (right) presented a plaque to U.S. President Richard Milhous Nixon (left) on behalf of all people who had taken part in the space program. In making the presentation, Armstrong said 'Mr. President, you have proclaimed this week to be United States Space week in conjunction with the fifth anniversary of our first successful landing on the Moon. It is my privilege to represent my colleagues, the crewmen of projects Mercury, Gemini, Apollo, and Skylab, and the men and women of NASA, and the hundreds of thousands of Americans from across the land who contributed so mightily to the success of our efforts in space in presenting this plaque which bears the names of each individual who has had the privilege of representing this country' in a space flight. The presentation was made at the California white house in San Clemente.

  10. Optical detection of structural changes in human carotid atherosclerotic plaque

    NASA Astrophysics Data System (ADS)

    Korol, R. M.; Canham, P. B.; Finlay, H. M.; Hammond, R. R.; Quantz, M.; Ferguson, G. G.; Liu, L. Y.; Lucas, A. R.

    2005-08-01

    Background: Arterial bifurcations are commonly the sites of developing atherosclerotic plaque that lead to arterial occlusions and plaque rupture (myocardial infarctions and strokes). Laser induced fluorescence (LIF) spectroscopy provides an effective nondestructive method supplying spectral information on extracellular matrix (ECM) protein composition, specifically collagen and elastin. Purpose: To investigate regional differences in the ECM proteins -- collagen I, III and elastin in unstable plaque by analyzing data from laser-induced fluorescence spectroscopy of human carotid endarterectomy specimens. Methods: Gels of ECM protein extracts (elastin, collagen types I & III) were measured as reference spectra and internal thoracic artery segments (extra tissue from bypass surgery) were used as tissue controls. Arterial segments and the endarterectomy specimens (n=21) were cut into 5mm cross-sectional rings. Ten fluorescence spectra per sampling area were then recorded at 5 sites per ring with argon laser excitation (357nm) with a penetration depth of 200 ?m. Spectra were normalized to maximum intensity and analyzed using multiple regression analysis. Tissue rings were fixed in formalin (within 3 hours of surgery), sectioned and stained with H&E or Movat's Pentachrome for histological analysis. Spectroscopy data were correlated with immunohistology (staining for elastin, collagen types I, III and IV). Results: Quantitative fluorescence for the thoracic arteries revealed a dominant elastin component on the luminal side -- confirmed with immunohistology and known artery structure. Carotid endarterectomy specimens by comparison had a significant decrease in elastin signature and increased collagen type I and III. Arterial spectra were markedly different between the thoracic and carotid specimens. There was also a significant elevation (p<0.05) of collagen type I distal to the bifurcation compared to proximal tissue in the carotid specimens. Conclusion: Fluorescence spectroscopy is an effective method for evaluating ECM (collagen and elastin) associated with vascular remodeling despite the considerable variability in the plaque structure. Consistent regional differences were detected in the carotid specimens.

  11. Copper, iron and zinc in Alzheimer's disease senile plaques

    Microsoft Academic Search

    M. A Lovell; J. D Robertson; W. J Teesdale; J. L Campbell; W. R Markesbery

    1998-01-01

    Concentrations of copper (Cu), iron (Fe) and zinc (Zn) were measured in the rims and cores of senile plaques (SP) and in the neuropil of the amygdala of nine Alzheimer's disease (AD) patients and in the neuropil of the amygdala of five neurologically normal control subjects using micro particle-induced X-ray emission (micro-PIXE). Comparison of SP rim and core values revealed

  12. Perforin expression in plaque psoriasis: an immunohistochemical study.

    PubMed

    Samaka, Rehab Monir; Gaber, Mohamed A; Metwe, Nermin A

    2015-04-01

    Psoriasis (PsO) is T-cell-mediated disease resulting from aberrant activation of both innate and adaptive immunity. Perforin is a multi-domain, pore-forming protein. It is located within the cytoplasm of CD 8 cytotoxic T cells (CTLs) and natural killer cells (NK). The aim of this study was to evaluate the immunohistochemical (IHC) expression of perforin in lesional and perilesional skin of chronic plaque psoriatic patient and correlate its expression with the standard clinico-pathological variables. This prospective case-control study was conducted on 50 PsO patients and 30 age- and gender-matched healthy subjects as a control group. There were high-significant differences between lesional and perilesional skin of plaque PsO patients as regards to IHC perforin status and localization (p?plaque PsO. Plaque psoriatic patients with positive perforin expression could be a candidate for a future target therapy to stop the proposed scenario and achieve a therapeutic response. PMID:25222509

  13. Detection of Atherosclerotic Coronary Plaques by Fluorescence Lifetime Imaging Angioscopy 

    E-print Network

    Thomas, Patrick A.

    2010-10-12

    waves. This presents a problem by masking any features behind the calcium deposit (11). Optical Coherence Tomography (OCT) presents another way to scan the physical tomography of a surface, giving similar information as IVUS. OCT has received a... technique for intravascular detection of atherosclerotic plaque is Intravascular Ultrasound, or IVUS. IVUS is the adaption of ultrasonography to intravascular applications and returns A-line scans (A-line scans are lines of spatially resolved information...

  14. Clinical safety of tazarotene in the treatment of plaque psoriasis

    Microsoft Academic Search

    Ronald Marks

    1997-01-01

    Oral retinoids are effective in the treatment of psoriasis, but their use is limited by concerns for teratogenic potential and systemic side effects. Tazarotene is a novel acetylenic retinoid undergoing clinical trials for the topical treatment of mild-to-moderate plaque psoriasis. The safety and tolerability of tazarotene 0.1% and 0.05% gels were examined in a series of preclinical and clinical trials.

  15. Patient specific multiscale modelling for plaque formation and progression.

    PubMed

    Exarchos, T P; Sakellarios, A; Siogkas, P K; Fotiadis, D I; Milosevic, Z; Nikolic, D; Filipovic, N; Marraccini, P; Vozzi, F; Parodi, O

    2012-01-01

    We present a three-dimensional model of plaque formation and progression that was tested in a set of patients who underwent coronary Computed Tomography angiography (CTA) for anginal symptoms. The 3D blood flow is described by the Navier-Stokes equations, together with the continuity equation. Mass transfer within the blood lumen and through the arterial wall is coupled with the blood flow and is modeled by a convection-diffusion equation. The Low Density Lipoprotein (LDL) transports in lumen of the vessel and through the vessel tissue (which has a mass consumption term) are coupled by Kedem-Katchalsky equations. The inflammatory process is modeled using three additional reaction-diffusion partial differential equations. A full three-dimensional model was created. Furthermore, features potentially affecting plaque growth, such as patient risk score, circulating biomarkers, localization and composition of the initial plaque, and coronary vasodilating capability were also investigated. The proof of concept of the model effectiveness was assessed 6 months after the baseline evaluation. PMID:23366529

  16. Adherence of plaque components to different restorative materials.

    PubMed

    Kawai, K; Urano, M

    2001-01-01

    This study compared the amount of artificial plaque synthesized in vitro by Streptococcus sobrinus on various dental materials using radioisotopes. In particular, plaque-retaining capacities of new types of ceramics were the focus of this study. Specimens were fabricated from the following materials (one amalgam alloy [Spherical-D], one casting gold alloy [Casting Gold TYPE I], one resin composite [Herculite XR] and three ceramics [Vita Celay Blanks, IPS Empress and Dicor MGC]). The amount of bacteria and glucans adhered on the specimens was measured after incubation for 24 hours at 37 degrees C with radio-labeled cariogenic bacteria and sucrose. This adhesion test was performed using two different surfaces with 600-grit roughness and clinical smoothness. Irrespective of the surface roughness, the least amount of plaque adhered to the ceramics. However, in the case of the resin composite and amalgam, the amount of bacteria and glucan adhesion decreased dramatically by polishing, though there were no statistically different changes in the amount of bacteria and glucans that adhered to the ceramics even after polishing. In general, the amount of adhered bacteria showed almost the same tendency as that of glucans. Although no statistical differences in the amount of bacteria and glucan adhesion were detected among the three ceramics investigated in this study, a lesser amount of bacteria and glucans adhered to them compared to the other materials. PMID:11504440

  17. HDL-mimetic PLGA nanoparticle to target atherosclerosis plaque macrophages.

    PubMed

    Sanchez-Gaytan, Brenda L; Fay, Francois; Lobatto, Mark E; Tang, Jun; Ouimet, Mireille; Kim, YongTae; van der Staay, Susanne E M; van Rijs, Sarian M; Priem, Bram; Zhang, Liangfang; Fisher, Edward A; Moore, Kathryn J; Langer, Robert; Fayad, Zahi A; Mulder, Willem J M

    2015-03-18

    High-density lipoprotein (HDL) is a natural nanoparticle that exhibits an intrinsic affinity for atherosclerotic plaque macrophages. Its natural targeting capability as well as the option to incorporate lipophilic payloads, e.g., imaging or therapeutic components, in both the hydrophobic core and the phospholipid corona make the HDL platform an attractive nanocarrier. To realize controlled release properties, we developed a hybrid polymer/HDL nanoparticle composed of a lipid/apolipoprotein coating that encapsulates a poly(lactic-co-glycolic acid) (PLGA) core. This novel HDL-like nanoparticle (PLGA-HDL) displayed natural HDL characteristics, including preferential uptake by macrophages and a good cholesterol efflux capacity, combined with a typical PLGA nanoparticle slow release profile. In vivo studies carried out with an ApoE knockout mouse model of atherosclerosis showed clear accumulation of PLGA-HDL nanoparticles in atherosclerotic plaques, which colocalized with plaque macrophages. This biomimetic platform integrates the targeting capacity of HDL biomimetic nanoparticles with the characteristic versatility of PLGA-based nanocarriers. PMID:25650634

  18. Reproducibility of two 3-D ultrasound carotid plaque quantification methods.

    PubMed

    Græbe, Martin; Entrekin, Robert; Collet-Billon, Antoine; Harrison, Gerard; Sillesen, Henrik

    2014-07-01

    Compared with single 2-D images, emerging 3-D ultrasound technologies hold the promise of reducing variability and increasing sensitivity in the quantification of carotid plaques for individual cardiovascular risk stratification. Inter- and intra-observer agreement between a manual, cross-sectional, 2-D freehand sweep and a mechanical 3-D ultrasound investigation of 62 carotid artery plaques is reported with intra-class correlation coefficients (with 95% confidence intervals). Inter-observer agreement was 0.60 (0.29-0.77) for the freehand method and 0.89 (0.83-0.93) for the mechanical 3-D acquisition. The use of semi-automated computerized planimetric measurements of plaque burden has high intra-observer repeatability, but is vulnerable to systematic inter-observer differences. For the 2-D freehand sweep, a considerable contribution to variation is introduced by the scanning procedure itself, that is, the lack of controlled motion along the third dimension. Future implementation of 3-D ultrasound quantification in large-scale studies of inter-individual cardiovascular risk assessment seems justified using the methods described. PMID:24726799

  19. Use of food colourants as plaque disclosing agents.

    PubMed

    Kieser, J B; Wade, A B

    1976-11-01

    The effectiveness of plaque disclosure by several liquid food colourants and disclosing agents was compared in a group of eight subjects. The subjects refrained from all forms of oral hygiene for a 48-hour period prior to rinsing with 5 ml of each dye in turn at weekly intervals. Kodachrome film records were taken and projected for the assessment at weekly intervals. Kodachrome film records were taken and projected for the assessment of plaque staining efficacy by a panel of 38 assessors. Acceptability with respect to taste, extent and duration of mucosal staining and any side effects was also evaluated. The food colourants were as effective as the disclosing agents. Ability to stain plaque appears to be related not only to the constituents of each dye, but also to their concentrations and relative proportions. Other desirable properties of an ideal disclosing agent tended to be fulfilled to a level equivalent to, or better than, that reached by the proprietery disclosing agents. Difficulty in obtaining proprietary disclosing agents should not act as a handicap to achieving better levels of oral cleanliness as inexpensive food colourants of equal effectiveness to the best proprietary agent are readily available. PMID:62762

  20. [Ultrasound-guided ESWT in Peyronie's disease plaques].

    PubMed

    Mirone, V; Palmieri, A; Granata, A M; Piscopo, A; Verze, P; Ranavolo, R

    2000-12-01

    The aim of the study was to check the efficiency of shock waves in the treatment of Peyronie's disease. The instrument, because of its lithotriptic power, already used in the treatment of orthopedic disease and salivary stones, can be used to break plaques in induratio penis plastica. A total of 481 patients affected with Peyronie's disease were entered into a prospective trial. Patients with big plaques or with an initial stage of degeneration were excluded. We divided the patients into three treatment groups: a) shock waves alone in 56 patients; b) a combination of shock waves and calcioantagonist (perilesional injection) in 324 patients; c) calcioantagonist alone in 101 patients. The group of 101 patients (group C) treated during the previous 2 years with a medical therapy based only on the injection of calcioantagonist, was used as a control group. Ultrasound evaluation of the treated plaques showed a reduction of size in 27/56 patients of the group A, in 159/324 patients of the group B and in 39/101 patients of group C. Painful erection improved in the 91.5% of group B, against the 45.7% of group C. Furthermore, we pointed out, with interviews to the patients, a considerable improvement of the pain and of the sexual performances. The therapeutic association of shock waves with calcioantagonist injections is an effective non-operative treatment for the stabilization of Peyronie's disease. PMID:11221076

  1. Pravastatin Treatment Increases Collagen Content and Decreases Lipid Content, Inflammation, Metalloproteinases, and Cell Death in Human Carotid Plaques Implications for Plaque Stabilization

    Microsoft Academic Search

    Milita Crisby; Gunilla Nordin-Fredriksson; Prediman K. Shah; Juliana Yano; Jenny Zhu; Jan Nilsson

    Background—The clinical benefits of lipid lowering with statins are attributed to changes in plaque composition leading to lesion stability, but supporting clinical data from human studies are lacking. Therefore, we investigated the effect of 3 months of pravastatin treatment on composition of human carotid plaques removed during carotid endarterectomy. Methods and Results—Consecutive patients with symptomatic carotid artery stenosis received 40

  2. Visualization of the biochemical markers of atherosclerotic plaque with the use of Raman, IR and AFM.

    PubMed

    Marzec, Katarzyna M; Wrobel, Tomasz P; Rygula, Anna; Maslak, Edyta; Jasztal, Agnieszka; Fedorowicz, Andrzej; Chlopicki, Stefan; Baranska, Malgorzata

    2014-09-01

    In this work, we describe a methodology to visualize the biochemical markers of atherosclerotic plaque in cross sections of brachiocephalic arteries (BCA) taken from ApoE/LDLR(-/-) mice. The approach of the visualization of the same area of atherosclerotic plaque with the use of Raman, IR and AFM imaging enables the parallel characterisation of various features of atherosclerotic plaques. This support to the histochemical staining is utilized mainly in studies on mice models of atherosclerotic plaques, where micro and sub-micro resolutions are required. This work presents the methodology of the measurement and visualization of plaque features important for atherosclerosis development and plaques vulnerability analysis. Label-free imaging of cholesterol, cholesteryl esters, remodeled media, heme, internal elastic lamina, fibrous cap and calcification provides additional knowledge to previously presented quantitative measurements of average plaque features. AFM imaging enhanced the results obtained with the use of vibrational microspectroscopies with additional topographical information of the sample. To the best of our knowledge, this is the first work which demonstrates that co-localized measurement of atherosclerotic plaque with Raman, IR and AFM imaging provides a comprehensive insight into the biochemical markers of atherosclerotic plaques, and can be used as an integrated approach to assess vulnerability of the plaque. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim). PMID:24604883

  3. Short-term consumption of probiotic lactobacilli has no effect on acid production of supragingival plaque.

    PubMed

    Marttinen, Aino; Haukioja, Anna; Karjalainen, Sára; Nylund, Lotta; Satokari, Reetta; Öhman, Carina; Holgerson, Pernilla; Twetman, Svante; Söderling, Eva

    2012-06-01

    Acidogenicity and the levels of mutans streptococci (MS) in dental plaque after the use of Lactobacillus rhamnosus GG (LGG) and Lactobacillus reuteri were determined. The study had a randomised, double-blind, crossover design. Thirteen volunteers used tablets containing LGG or a combination of L. reuteri SD2112 and PTA 5289 for 2 weeks. At baseline and at the end of each tablet period, all available supragingival plaque was collected. Lactic acid production was determined from a fixed volume (8 ?l) of fresh plaque and the rest of the plaque was used for culturing MS and lactobacilli. The retention of probiotics to the plaque was assessed using PCR techniques. No probiotic-induced changes were found in the acidogenicity of plaque. Also, MS counts remained at the original level. The number of subjects with lactobacilli in plaque increased in the L. reuteri group (p = 0.011) but not in the LGG group. PCR analysis of plaque revealed the presence of LGG in four and L. reuteri in six subjects after the use of the probiotic. The use of the lactobacilli did not affect the acidogenicity or MS levels of plaque. Short-term consumption of LGG and L. reuteri appeared not to influence the acidogenicity of plaque. PMID:21732090

  4. Carotid intima-media thickness and plaque in cardiovascular risk assessment.

    PubMed

    Naqvi, Tasneem Z; Lee, Ming-Sum

    2014-10-01

    Carotid intima-media thickness (CIMT) has been shown to predict cardiovascular (CV) risk in multiple large studies. Careful evaluation of CIMT studies reveals discrepancies in the comprehensiveness with which CIMT is assessed-the number of carotid segments evaluated (common carotid artery [CCA], internal carotid artery [ICA], or the carotid bulb), the type of measurements made (mean or maximum of single measurements, mean of the mean, or mean of the maximum for multiple measurements), the number of imaging angles used, whether plaques were included in the intima-media thickness (IMT) measurement, the report of adjusted or unadjusted models, risk association versus risk prediction, and the arbitrary cutoff points for CIMT and for plaque to predict risk. Measuring the far wall of the CCA was shown to be the least variable method for assessing IMT. However, meta-analyses suggest that CCA-IMT alone only minimally improves predictive power beyond traditional risk factors, whereas inclusion of the carotid bulb and ICA-IMT improves prediction of both cardiac risk and stroke risk. Carotid plaque appears to be a more powerful predictor of CV risk compared with CIMT alone. Quantitative measures of plaques such as plaque number, plaque thickness, plaque area, and 3-dimensional assessment of plaque volume appear to be progressively more sensitive in predicting CV risk than mere assessment of plaque presence. Limited data show that plaque characteristics including plaque vascularity may improve CV disease risk stratification further. IMT measurement at the CCA, carotid bulb, and ICA that allows inclusion of plaque in the IMT measurement or CCA-IMT measurement along with plaque assessment in all carotid segments is emerging as the focus of carotid artery ultrasound imaging for CV risk prediction. PMID:25051948

  5. Characterizing the appearance and growth of amyloid plaques in APP/PS1 mice.

    PubMed

    Yan, Ping; Bero, Adam W; Cirrito, John R; Xiao, Qingli; Hu, Xiaoyan; Wang, Yan; Gonzales, Ernesto; Holtzman, David M; Lee, Jin-Moo

    2009-08-26

    Amyloid plaques are primarily composed of extracellular aggregates of amyloid-beta (Abeta) peptide and are a pathological signature of Alzheimer's disease. However, the factors that influence the dynamics of amyloid plaque formation and growth in vivo are largely unknown. Using serial intravital multiphoton microscopy through a thinned-skull cranial window in APP/PS1 transgenic mice, we found that amyloid plaques appear and grow over a period of weeks before reaching a mature size. Growth was more prominent early after initial plaque formation: plaques grew faster in 6-month-old compared with 10-month-old mice. Plaque growth rate was also size-related, as smaller plaques exhibited more rapid growth relative to larger plaques. Alterations in interstitial Abeta concentrations were associated with changes in plaque growth. Parallel studies using multiphoton microscopy and in vivo microdialysis revealed that pharmacological reduction of soluble extracellular Abeta by as little as 20-25% was associated with a dramatic decrease in plaque formation and growth. Furthermore, this small reduction in Abeta synthesis was sufficient to reduce amyloid plaque load in 6-month-old but not 10-month-old mice, suggesting that treatment early in disease pathogenesis may be more effective than later treatment. In contrast to thinned-skull windows, no significant plaque growth was observed under open-skull windows, which demonstrated extensive microglial and astrocytic activation. Together, these findings indicate that individual amyloid plaque growth in vivo occurs over a period of weeks and may be influenced by interstitial Abeta concentration as well as reactive gliosis. PMID:19710322

  6. Characterising human atherosclerotic carotid plaque tissue composition and morphology using combined spectroscopic and imaging modalities

    PubMed Central

    2015-01-01

    Calcification is a marked pathological component in carotid artery plaque. Studies have suggested that calcification may induce regions of high stress concentrations therefore increasing the potential for rupture. However, the mechanical behaviour of the plaque under the influence of calcification is not fully understood. A method of accurately characterising the calcification coupled with the associated mechanical plaque properties is needed to better understand the impact of calcification on the mechanical behaviour of the plaque during minimally invasive treatments. This study proposes a comparison of biochemical and structural characterisation methods of the calcification in carotid plaque specimens to identify plaque mechanical behaviour. Biochemical analysis, by Fourier Transform Infrared (FTIR) spectroscopy, was used to identify the key components, including calcification, in each plaque sample. However, FTIR has a finite penetration depth which may limit the accuracy of the calcification measurement. Therefore, this FTIR analysis was coupled with the identification of the calcification inclusions located internally in the plaque specimen using micro x-ray computed tomography (?X-CT) which measures the calcification volume fraction (CVF) to total tissue content. The tissue characterisation processes were then applied to the mechanical material plaque properties acquired from experimental circumferential loading of human carotid plaque specimen for comparison of the methods. FTIR characterised the degree of plaque progression by identifying the functional groups associated with lipid, collagen and calcification in each specimen. This identified a negative relationship between stiffness and 'lipid to collagen' and 'calcification to collagen' ratios. However, ?X-CT results suggest that CVF measurements relate to overall mechanical stiffness, while peak circumferential strength values may be dependent on specific calcification geometries. This study demonstrates the need to fully characterise the calcification structure of the plaque tissue and that a combination of FTIR and ?X-CT provides the necessary information to fully understand the mechanical behaviour of the plaque tissue. PMID:25602176

  7. Shed Membrane Microparticles With Procoagulant Potential in Human Atherosclerotic Plaques A Role for Apoptosis in Plaque Thrombogenicity

    Microsoft Academic Search

    Ziad Mallat; Benedicte Hugel; Jeanny Ohan; Guy Leseche; Jean-Marie Freyssinet; Alain Tedgui

    Background—The specific role of apoptosis in human atherosclerosis remains unknown. During apoptotic cell death, phosphatidylserine exposure on the cell surface confers a high tissue-factor (TF)- dependent procoagulant activity. Methods and Results—In this study, we examined the role of apoptotic cell death in the promotion of plaque thrombogenicity. TF expression and its relation to apoptosis was analyzed in 16 human atherosclerotic

  8. Detection of high-risk atherosclerotic plaques by magnetic resonance imaging.

    PubMed

    Noguchi, Teruo; Yamada, Naoaki; Kawasaki, Tomohiro; Tanaka, Atsushi; Yasuda, Satoshi

    2013-01-01

    The goal of coronary plaque burden assessment is to detect vulnerable or high-risk atherosclerotic plaques that are prone to rupture and to stabilize them through pharmacologic and other types of interventions before the development of acute coronary syndrome. In this regard, a reliable, reproducible, and less invasive imaging modality capable of identifying plaque characteristics associated with plaque vulnerability would be immensely useful for evaluating plaque status and predicting future cardiovascular events. Recently, magnetic resonance imaging (MRI) has emerged as a novel modality for atherosclerotic plaque detection and characterization. This review will cover the developments in MRI for characterizing atherosclerosis in carotid and coronary arteries and its use in clinical diagnoses and longitudinal studies to understand the pathophysiology of atherosclerosis. PMID:23877708

  9. Increased expression of endothelial lipase in symptomatic and unstable carotid plaques

    Microsoft Academic Search

    Matias Trbuši?; Monika Riederer; Majda Vu?i?; Ivo Lovri?evi?; Božo Krušlin; Martin Gauster; Sonja Mohrenz; Andrea Berghold; Beate Tiran; Vesna Degoricija; Saša Frank

    The aim of this study was to evaluate endothelial lipase (EL) protein expression in advanced human carotid artery plaques\\u000a (HCAP) with regard to plaque (in)stability and the incidence of symptoms. HCAP were collected from 66 patients undergoing\\u000a carotid endarterectomy (CEA). The degree of plaque (in)stability was estimated by ultrasound and histology. In HCAP sections,\\u000a EL expression was determined by immunostaining

  10. Evidence for a Proinflammatory and Proteolytic Environment in Plaques From Endarterectomy Segments of Human Carotid Arteries

    Microsoft Academic Search

    Marilena Formato; Miriam Farina; Rita Spirito; Marco Maggioni; Anna Guarino; Gian Mario Cherchi; Paolo Biglioli; Celina Edelstein; Angelo M. Scanu

    2010-01-01

    Objectives—Based on previous observations on apolipoprotein(a), apo(a), in human unstable carotid plaques, we explored whether in the inflammatory environment of human atheroma, proteolytic events affect other hepatic and topically generated proteins in relation to the issue of plaque stability. Methods and Results—Forty unstable and 24 stable plaques from endarterectomy segments of affected human carotid arteries were extracted with buffered saline

  11. Genetic deletion or TWEAK blocking antibody administration reduce atherosclerosis and enhance plaque stability in mice

    PubMed Central

    Sastre, Cristina; Fernández-Laso, Valvanera; Madrigal-Matute, Julio; Muñoz-García, Begoña; Moreno, Juan A; Pastor-Vargas, Carlos; Llamas-Granda, Patricia; Burkly, Linda C; Egido, Jesús; Martín-Ventura, Jose L; Blanco-Colio, Luis M

    2014-01-01

    Clinical complications associated with atherosclerotic plaques arise from luminal obstruction due to plaque growth or destabilization leading to rupture. Tumour necrosis factor ligand superfamily member 12 (TNFSF12) also known as TNF-related weak inducer of apoptosis (TWEAK) is a proinflammatory cytokine that participates in atherosclerotic plaque development, but its role in plaque stability remains unclear. Using two different approaches, genetic deletion of TNFSF12 and treatment with a TWEAK blocking mAb in atherosclerosis-prone mice, we have analysed the effect of TWEAK inhibition on atherosclerotic plaques progression and stability. Mice lacking both TNFSF12 and Apolipoprotein E (TNFSF12?/?ApoE?/?) exhibited a diminished atherosclerotic burden and lesion size in their aorta. Advanced atherosclerotic plaques of TNFSF12?/?ApoE?/? or anti-TWEAK treated mice exhibited an increase collagen/lipid and vascular smooth muscle cell/macrophage ratios compared with TNFSF12+/+ApoE?/? control mice, reflecting a more stable plaque phenotype. These changes are related with two different mechanisms, reduction of the inflammatory response (chemokines expression and secretion and nuclear factor kappa B activation) and decrease of metalloproteinase activity in atherosclerotic plaques of TNFSF12?/?ApoE?/?. A similar phenotype was observed with anti-TWEAK mAb treatment in TNFSF12+/+ApoE?/? mice. Brachiocephalic arteries were also examined since they exhibit additional features akin to human atherosclerotic plaques associated with instability and rupture. Features of greater plaque stability including augmented collagen/lipid ratio, reduced macrophage content, and less presence of lateral xanthomas, buried caps, medial erosion, intraplaque haemorrhage and calcium content were present in TNFSF12?/?ApoE?/? or anti-TWEAK treatment in TNFSF12+/+ApoE?/? mice. Overall, our data indicate that anti-TWEAK treatment has the capacity to diminish proinflamatory response associated with atherosclerotic plaque progression and to alter plaque morphology towards a stable phenotype. PMID:24479820

  12. Mapping the Genetic Determinants of Pathogenicity and Plaque Phenotype in Swine Vesicular Disease Virus

    Microsoft Academic Search

    TORU KANNO; DAVID MACKAY; TORU INOUE; GINETTE WILSDEN; MAKOTO YAMAKAWA; REIKO YAMAZOE; SHIGEO YAMAGUCHI; JUNSUKE SHIRAI; PAUL KITCHING; YOSUKE MURAKAMI

    1999-01-01

    A series of recombinant viruses were constructed using infectious cDNA clones of the virulent J1'73 (large plaque phenotype) and the avirulent H\\/3'76 (small plaque phenotype) strains of swine vesicular disease virus to identify the genetic determinants of pathogenicity and plaque phenotype. Both traits could be mapped to the region between nucleotides (nt) 2233 and 3368 corresponding to the C terminus

  13. Structure-dependent dynamic mechanical behavior of fibrous caps from human atherosclerotic plaques

    Microsoft Academic Search

    Richard T. Lee; Alan J. Grodzinsky; Eliot H. Frank; Roger D. Kamm; Fj Schoen

    2010-01-01

    Background. Although thrombosis associated witha fissured atherosclerotic plaque is believed tobethemostcommon causeofacute coronarysyndromes, theunderlying factors that trigger plaque rupture arecurrently unknown. However, themechanical behavior oftheplaque isprobably ofcritical importance. Methods andResults. Totestthehypothesis thatthemechanical properties ofa plaque are dependent on itscomposition and,inparticular, thatthestiffness offibrous capschanges within therangeoffrequencies carried bya physiological pressurewave,thestress-strain relation was studied in27fibrous capsandrelated totheunderlying histological structure of thefibrous cap.Fibrous

  14. Increased ADRP expression in human atherosclerotic lesions correlates with plaque instability

    PubMed Central

    Xu, Bin; Zhao, Huiying; Wang, Shengnan; Sun, Xiwei; Qin, Xiujiao

    2015-01-01

    Adipose differentiation-related protein (ADRP) is intrinsically associated with the surface of lipid droplets implicated in the development of atherosclerosis. We analyzed expression of ADRP in human popliteal artery plaques. Atherosclerotic plaque tissue from the popliteal artery was obtained from 18 patients undergoing lower extremity amputation for arteriosclerosis obliterans, and with either stable (n = 6) or unstable (n = 12) atherosclerotic plaques. Plaques were histologically classified as either unstable (? 40% lipid core plaque area) or stable (< 40% lipid core plaque area). Control tissues consisted of sections of mesenteric arteries obtained from 10 patients without a history of atherosclerosis, but undergoing a subtotal gastrectomy. Plaque tissues were analyzed for expression of ADRP and protein kinase C (PKC) protein by immunohistochemical methods, and ADRP mRNA expression was measured using the reverse transcription polymerase chain reaction (RT-PCR). Immunohistochemical analyses showed that ADRP expression was higher in samples of unstable plaque when compared with expression in stable plaque (gray intensities 103.56 ± 1.187 vs 106.95 ± 1.389, respectively, P < 0.05) and that ADRP expression was associated with increased PKC expression (gray intensities 102.32 ± 1.730 vs 104.70 ± 0.959, respectively, P < 0.01). Consistent with ADRP protein expression, expression of ADRP mRNA was also higher in unstable plaque compared to expression in stable plaque (relative expression 1.17 ± 0.15 vs 0.81 ± 0.03, respectively, P < 0.05). In conclusion: this study demonstrated that increased expression of ADRP in human atherosclerosis was associated with plaque instability.

  15. Murine Coronaviruses: Isolation and Characterization of Two Plaque Morphology Variants of the JHM Neurotropic Strain

    Microsoft Academic Search

    STEPHEN A. STOHLMAN; PETER R. BRAYTON; JOHN O. FLEMING; LESLIE P. WEINER; MICHAEL M. C. LAI

    1982-01-01

    SUMMARY Two plaque-size variants of the neurotropic JHM strain of mouse hepatitis virus have been isolated from the virus stock after eight serial passages in suckling mouse brain. One variant, JHM-DL, produces large plaques, while the other, JHM-DS, produces small plaques in tissue culture. DS replicates more slowly, has a lower virus yield in vitro, and is less virulent for

  16. Endothelial shear stress in the evolution of coronary atherosclerotic plaque and vascular remodelling: current understanding and remaining questions.

    PubMed

    Wentzel, Jolanda J; Chatzizisis, Yiannis S; Gijsen, Frank J H; Giannoglou, George D; Feldman, Charles L; Stone, Peter H

    2012-11-01

    The heterogeneity of plaque formation, the vascular remodelling response to plaque formation, and the consequent phenotype of plaque instability attest to the extraordinarily complex pathobiology of plaque development and progression, culminating in different clinical coronary syndromes. Atherosclerotic plaques predominantly form in regions of low endothelial shear stress (ESS), whereas regions of moderate/physiological and high ESS are generally protected. Low ESS-induced compensatory expansive remodelling plays an important role in preserving lumen dimensions during plaque progression, but when the expansive remodelling becomes excessive promotes continued influx of lipids into the vessel wall, vulnerable plaque formation and potential precipitation of an acute coronary syndrome. Advanced plaques which start to encroach into the lumen experience high ESS at their most stenotic region, which appears to promote plaque destabilization. This review describes the role of ESS from early atherogenesis to early plaque formation, plaque progression to advanced high-risk stenotic or non-stenotic plaque, and plaque destabilization. The critical implication of the vascular remodelling response to plaque growth is also discussed. Current developments in technology to characterize local ESS and vascular remodelling in vivo may provide a rationale for innovative diagnostic and therapeutic strategies for coronary patients that aim to prevent clinical coronary syndromes. PMID:22752349

  17. Near-infrared spectroscopy for intracoronary detection of lipid-rich plaques to understand atherosclerotic plaque biology in man and guide clinical therapy.

    PubMed

    Erlinge, D

    2015-08-01

    Ischaemic heart disease is the leading cause of death worldwide. The common denominator for plaques causing acute coronary syndrome (ACS) is lipid accumulation, either as a lipid core or lipid pools. An intracoronary imaging device to detect lipid-rich plaques (LRPs) could therefore identify most of the plaques causing ACS and sudden death. Near-infrared spectroscopy combined with intravascular ultrasound (NIRS-IVUS) is a promising new intracoronary imaging method that is able to specifically quantify lipid accumulation measured as the lipid core burden index (LCBI). NIRS-IVUS is highly specific for the identification of ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI) culprit plaques usually in the form of a circular LRP. NIRS-IVUS may assist in defining the aetiology of coronary events. The effect of cholesterol-lowering therapy on the lipid core can be measured in coronary plaques in patients, and NIRS-IVUS may be a useful tool for drug development in phase II studies as a surrogate end-point for future ACS. Plaques with a high LCBI have an increased risk of peri-procedural events. NIRS-IVUS can help to define the diameter and length of stents to avoid procedure-related complications. Increased coronary LCBI predicts a higher risk of future cardiovascular events. Lipid core detection using NIRS may help to identify vulnerable plaques to treat them before they cause ACS or sudden death. PMID:26096457

  18. [Near-infrared spectroscopy (NIRS), new intracoronary imaging technique of unstable coronary plaque].

    PubMed

    Ondrúš, Tomáš; Ka?ovský, Jan; Poloczek, Martin; Miklík, Roman; Bo?ek, Otakar; Je?ábek, Petr; Kala, Petr

    2014-01-01

    Acute coronary syndrome may develop in the background of hemodynamically non-significant coronary artery disease. It may be caused by the presence of "vulnerable plaque", which is characterized by the lipid rich core and thin fibrous cap content. NIRS - near infrared spectroscopy - is a morphological imaging method allowing determining atherosclerotic plaque cholesterol burden. Information about the chemical composition may contribute to "high risk" plaque early identification and subsequent optimal interventional strategy. The first experience with the clinical implementation of this novel method is demonstrated in a case report. Key words: acute coronary syndrome - chemogram - intravascular imaging - NIRS - vulnerable plaque. PMID:24974760

  19. Comparison of strain rates of dart impacted plaques and pendulum impacted bumpers

    SciTech Connect

    Scammell, K.L.

    1987-01-01

    The difference in strain rates prevailing during pendulum impact of bumpers versus high speed dart impact of plaques was investigated. Uni-axial strain gages were applied to the tension side of the plaques and bumpers directly opposite the point of impact. The plaques were impacted with an instrumented high rate dart impact tester and the bumpers impacted with a full scale bumper pendulum impact tester. Theoretical calculations and actual strain rate data support the conclusion that the strain rate of a plaque during dart impact significantly exceeds that of bumper strain rate during pendulum impact.

  20. Biochemical comparison of plaque fluid on tooth and acrylic surfaces during a sucrose challenge.

    PubMed

    Rankine, C A; Smith, S L; Schneider, P E; Gardiner, D M

    1996-07-01

    Previous studies have investigated variations in dental plaque fluid composition within a single mouth after a sucrose exposure. The purpose of this study was to determine a potential source of calcium and phosphorus in plaque by comparing the pH, calcium and phosphorus concentrations in plaque fluid obtained from an acrylic appliance with samples taken from supragingival tooth surfaces within the same individual after a sucrose challenge. Separate plaque samples from 14 individuals were collected from an acrylic appliance or tooth surfaces within same individual before and 15 min after a 20% sucrose rinse. Each plaque sample was centrifuged and nanolitre samples of plaque fluid were analysed for pH with a pH microelectrode, for total calcium concentration by atomic absorption in a graphite furnace, and for phosphorus concentration by spectrophotometry. There was an increase in the calcium and phosphorus concentration in the plaque after the sucrose challenge and a significant increase in calcium and phosphorus concentrations in the plaque taken from the teeth compared to the acrylic surfaces. The results indicate that the increased total calcium and phosphorus in plaque during a sucrose challenge is probably derived from the demineralization of enamel or extracellular demineralized components. PMID:9015571

  1. Intraplaque haemorrhages as the trigger of plaque vulnerability

    PubMed Central

    Michel, Jean-Baptiste; Virmani, Renu; Arbustini, Eloïsa; Pasterkamp, Gerard

    2011-01-01

    Atherothrombosis remains one of the main causes of morbidity and mortality in the western countries. Human atherothrombotic disease begins early in life in relation to circulating lipid retention in the inner vascular wall. Risk factors enhance the progression towards clinical expression: dyslipidaemia, diabetes, smoking, hypertension, ageing, etc. The evolution from the initial lipid retention in the arterial wall to clinical events is a continuum of increasingly complex biological processes. Current strategies to fight the consequences of atherothrombosis are orientated either towards the promotion of a healthy life style1 and preventive treatment of risk factors, or towards late interventional strategies.2 Despite this therapeutic arsenal, the incidence of clinical events remains dramatically high,3 dependent, at least in part, on the increasing frequency of type 2 diabetes and ageing. But some medical treatments, focusing only on prevention of the metabolic risk, have failed to reduce cardiovascular mortality, thus illustrating that our understanding of the pathophysiology of human atherothrombosis leading to clinical events remain incomplete. New paradigms are now emerging which may give rise to novel experimental strategies to improve therapeutic efficacy and prediction of disease progression. Recent studies strengthen the concept that the intraplaque neovascularization and bleeding (Figure 1, upper panel) are events that could play a major role in plaque progression and leucocyte infiltration, and may also serve as a measure of risk for the development of future events. The recent advances in our understanding of IntraPlaque Hemorrhage as a critical event in triggering acute clinical events have important implications for clinical research and possibly future clinical practice. Figure 1Macroscopic view and schematic representation of the detrimental consequences of intraplaque haemorrhages on plaque biology and stability. PMID:21398643

  2. Thiocyanate supplementation decreases atherosclerotic plaque in mice expressing human myeloperoxidase

    PubMed Central

    Morgan, P. E.; Laura, R. P.; Maki, R. A.; Reynolds, W. F.; Davies, M. J.

    2015-01-01

    Elevated levels of the heme enzyme myeloperoxidase (MPO) are associated with adverse cardiovascular outcomes. MPO predominantly catalyzes formation of the oxidants hypochlorous acid (HOCl) from Cl?, and hypothiocyanous acid (HOSCN) from SCN?, with these anions acting as competitive substrates. HOSCN is a less powerful and more specific oxidant than HOCl, and selectively targets thiols; such damage is largely reversible, unlike much HOCl-induced damage. We hypothesized that increased plasma SCN?, and hence HOSCN formation instead of HOCl, may decrease artery wall damage. This was examined using high-fat fed atherosclerosis-prone LDLR?/? mice transgenic for human MPO, with and without SCN? (10 mM) added to drinking water. Serum samples, collected fortnightly, were analyzed for cholesterol, triglycerides, thiols, MPO and SCN?; study-long exposure was calculated by area under the curve (AUC). Mean serum SCN? concentrations were elevated in the supplemented mice (200-320 ?M) relative to controls (<120 ?M). Normalized aortic root plaque areas at sacrifice were 26% lower in the SCN?-supplemented mice compared to controls (P=0.0417), but plaque morphology was not appreciably altered. Serum MPO levels steadily increased in mice on the high-fat diet, however, comparison of SCN?- supplemented vs. control mice showed no significant changes in MPO protein, cholesterol or triglyceride levels; thiol levels were decreased in supplemented mice at one time-point. Plaque areas increased with higher cholesterol AUC (r=0.4742; P=0.0468), and decreased with increasing SCN? AUC (r=?0.5693; P=0.0134). These data suggest that increased serum SCN? levels, which can be achieved in humans by dietary manipulation, may decrease atherosclerosis burden. PMID:25812586

  3. Thiocyanate supplementation decreases atherosclerotic plaque in mice expressing human myeloperoxidase.

    PubMed

    Morgan, P E; Laura, R P; Maki, R A; Reynolds, W F; Davies, M J

    2015-06-01

    Elevated levels of the heme enzyme myeloperoxidase (MPO) are associated with adverse cardiovascular outcomes. MPO predominantly catalyzes formation of the oxidants hypochlorous acid (HOCl) from Cl(-), and hypothiocyanous acid (HOSCN) from SCN(-), with these anions acting as competitive substrates. HOSCN is a less powerful and more specific oxidant than HOCl, and selectively targets thiols; such damage is largely reversible, unlike much HOCl-induced damage. We hypothesized that increased plasma SCN(-), and hence HOSCN formation instead of HOCl, may decrease artery wall damage. This was examined using high-fat fed atherosclerosis-prone LDLR(-/-) mice transgenic for human MPO, with and without SCN(-) (10 mM) added to drinking water. Serum samples, collected fortnightly, were analyzed for cholesterol, triglycerides, thiols, MPO, and SCN(-); study-long exposure was calculated by area under the curve (AUC). Mean serum SCN(-) concentrations were elevated in the supplemented mice (200-320 ?M) relative to controls (< 120 ?M). Normalized aortic root plaque areas at sacrifice were 26% lower in the SCN(-)-supplemented mice compared with controls (P = 0.0417), but plaque morphology was not appreciably altered. Serum MPO levels steadily increased in mice on the high-fat diet, however, comparison of SCN(-)-supplemented versus control mice showed no significant changes in MPO protein, cholesterol, or triglyceride levels; thiol levels were decreased in supplemented mice at one time-point. Plaque areas increased with higher cholesterol AUC (r = 0.4742; P = 0.0468), and decreased with increasing SCN(-) AUC (r = - 0.5693; P = 0.0134). These data suggest that increased serum SCN(-) levels, which can be achieved in humans by dietary manipulation, may decrease atherosclerosis burden. PMID:25812586

  4. Plaque pH modulations of children's favourite snacks.

    PubMed

    Gauba, K; Goyal, A; Tewari, A

    1991-03-01

    Cariogenic potential of a few children's favourite snacks, assessed by evaluation of pH modulations on their respective consumption after 2,5,10,20,30 and 40 minutes compared to 10 percent sucrose control using pooled plaque method, in 8-12 years old children revealed lollipop (hard sucking candy) to be the most cariogenic and samosa without chutney to be the least cariogenic. The cariogenic potential of ice creams were similar, however, low as compared to sucrose solution of 10 percent. PMID:2056343

  5. Integrated IVUS-OCT Imaging for Atherosclerotic Plaque Characterization

    PubMed Central

    Li, Xiang; Li, Jiawen; Jing, Joe; Ma, Teng; Liang, Shanshan; Zhang, Jun; Mohar, Dilbahar; Raney, Aidan; Mahon, Sari; Brenner, Matthew; Patel, Pranav; Shung, K. Kirk; Zhou, Qifa; Chen, Zhongping

    2014-01-01

    For the diagnosis of atherosclerosis, biomedical imaging techniques such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have been developed. The combined use of IVUS and OCT is hypothesized to remarkably increase diagnostic accuracy of vulnerable plaques. We have developed an integrated IVUS-OCT imaging apparatus, which includes the integrated catheter, motor drive unit, and imaging system. The dual-function imaging catheter has the same diameter of current clinical standard. The imaging system is capable for simultaneous IVUS and OCT imaging in real time. Ex vivo and in vivo experiments on rabbits with atherosclerosis were conducted to demonstrate the feasibility and superiority of the integrated intravascular imaging modality. PMID:24771992

  6. Bacteria Present in Carotid Arterial Plaques Are Found as Biofilm Deposits Which May Contribute to Enhanced Risk of Plaque Rupture

    PubMed Central

    Lanter, Bernard B.; Sauer, Karin

    2014-01-01

    ABSTRACT Atherosclerosis, a disease condition resulting from the buildup of fatty plaque deposits within arterial walls, is the major underlying cause of ischemia (restriction of the blood), leading to obstruction of peripheral arteries, congestive heart failure, heart attack, and stroke in humans. Emerging research indicates that factors including inflammation and infection may play a key role in the progression of atherosclerosis. In the current work, atherosclerotic carotid artery explants from 15 patients were all shown to test positive for the presence of eubacterial 16S rRNA genes. Density gradient gel electrophoresis of 5 of these samples revealed that each contained 10 or more distinct 16S rRNA gene sequences. Direct microscopic observation of transverse sections from 5 diseased carotid arteries analyzed with a eubacterium-specific peptide nucleic acid probe revealed these to have formed biofilm deposits, with from 1 to 6 deposits per thin section of plaque analyzed. A majority, 93%, of deposits was located proximal to the internal elastic lamina and associated with fibrous tissue. In 6 of the 15 plaques analyzed, 16S rRNA genes from Pseudomonas spp. were detected. Pseudomonas aeruginosa biofilms have been shown in our lab to undergo a dispersion response when challenged with free iron in vitro. Iron is known to be released into the blood by transferrin following interaction with catecholamine hormones, such as norepinephrine. Experiments performed in vitro showed that addition of physiologically relevant levels of norepinephrine induced dispersion of P. aeruginosa biofilms when grown under low iron conditions in the presence but not in the absence of physiological levels of transferrin. PMID:24917599

  7. Symptomatic carotid atherosclerotic disease: correlations between plaque composition and ipsilateral stroke risk

    PubMed Central

    Rothwell, Peter M; Redgrave, Jessica N; Moll, Frans L; de Vries, Jean-Paul PM; de Kleijn, Dominique PV; den Ruijter, Hester M; de Borst, Gert Jan; Pasterkamp, Gerard

    2014-01-01

    BACKGROUND AND PURPOSE For symptomatic patients with carotid artery stenosis the risk-benefit for surgical intervention may vary among patient groups. Various modalities of plaque imaging have been promoted as potential tools for additional risk stratification, particularly in patients with moderate stenosis. However, it remains uncertain to what extent carotid plaque components predict risk of future ipsilateral ischaemic stroke. METHODS In two large atherosclerotic carotid plaque biobank studies, we related histological characteristics of 1640 carotid plaques with a validated risk model for the prediction of individual 1- and 5-year stroke risk. RESULTS No significant heterogeneity between the studies was found. Predicted 5-year stroke risk (top versus bottom quartile) was related to plaque thrombus (OR=1.42, 95%CI 1.11-1.89, p=0.02), fibrous content (0.65, 0.49-0.87, p=0.004), macrophage infiltration (1.41, 1.05-1.90, p=0.02), high micro-vessel density (1.49, 1.05-2.11, p=0.03), and overall plaque instability (1.40, 1.05-1.87,p=0.02). This association was not observed for cap thickness, calcification, intra-plaque haemorrhage, or lymphocyte infiltration. Plaques removed within 30-days of most recent symptomatic event were most strongly correlated with predicted stroke risk. CONCLUSIONS Features of ‘the vulnerable carotid plaque’ including plaque thrombus, low fibrous content, macrophage infiltration and microvessel density correlate with predicted stroke risk. This study provides a basis for plaque imaging studies focused on stroke risk stratification. PMID:25477221

  8. Localization of Apoptotic Macrophages at the Site of Plaque Rupture in Sudden Coronary Death

    PubMed Central

    Kolodgie, Frank D.; Narula, Jagat; Burke, Allen P.; Haider, Nezam; Farb, Andrew; Hui-Liang, You; Smialek, John; Virmani, Renu

    2000-01-01

    Although apoptosis is a well-recognized phenomenon in chronic atherosclerotic disease, its role in sudden coronary death, in particular, acute plaque rupture is unknown. Culprit lesions from 40 cases of sudden coronary death were evaluated. Cases were divided into two mechanisms of death: ruptured plaques with acute thrombosis (n = 25) and stable plaques with and without healed myocardial infarction (n = 15). Apoptotic cells were identified by staining of fragmented DNA and confirmed in select cases by gold conjugate labeling combined with ultrastructural analysis. Additional studies were performed to examine the expression and activation of two inducers of apoptosis, caspases-1 and -3. Ruptured plaques showed extensive macrophage infiltration of the fibrous cap, in particular at rupture sites contrary to stable lesions, which contained fewer inflammatory cells. Among the culprit lesions, the overall incidence of apoptosis in fibrous caps was significantly greater in ruptured plaques (P < 0.001) and was predominantly localized to the CD68-positive macrophages. Furthermore, apoptosis at plaque rupture sites was more frequent than in areas of intact fibrous cap (P = 0.028). Plaque rupture sites demonstrated a strong immunoreactivity to caspase-1 within the apoptotic macrophages; staining for caspase-3 was weak. Immunoblot analysis of ruptured plaques demonstrated caspase-1 up-regulation and the presence of its active p20 subunit whereas stable lesions showed only the precursor; nonatherosclerotic control segments were negative for both precursor and active enzyme. These findings demonstrate extensive apoptosis of macrophages limited to the site of plaque rupture. The proteolytic cleavage of caspase-1 in ruptured plaques suggests activation of this apoptotic precursor. Whether macrophage apoptosis is essential to acute plaque rupture or is a response to the rupture itself remains to be determined. PMID:11021830

  9. Performance of digital RGB reflectance color extraction for plaque lesion

    NASA Astrophysics Data System (ADS)

    Hashim, Hadzli; Taib, Mohd Nasir; Jailani, Rozita; Sulaiman, Saadiah; Baba, Roshidah

    2005-01-01

    Several clinical psoriasis lesion groups are been studied for digital RGB color features extraction. Previous works have used samples size that included all the outliers lying beyond the standard deviation factors from the peak histograms. This paper described the statistical performances of the RGB model with and without removing these outliers. Plaque lesion is experimented with other types of psoriasis. The statistical tests are compared with respect to three samples size; the original 90 samples, the first size reduction by removing outliers from 2 standard deviation distances (2SD) and the second size reduction by removing outliers from 1 standard deviation distance (1SD). Quantification of data images through the normal/direct and differential of the conventional reflectance method is considered. Results performances are concluded by observing the error plots with 95% confidence interval and findings of the inference T-tests applied. The statistical tests outcomes have shown that B component for conventional differential method can be used to distinctively classify plaque from the other psoriasis groups in consistent with the error plots finding with an improvement in p-value greater than 0.5.

  10. Preliminary in vivo atherosclerotic carotid plaque characterization using the accumulated axial strain and relative lateral shift strain indices

    NASA Astrophysics Data System (ADS)

    Shi, Hairong; Mitchell, Carol C.; McCormick, Matthew; Kliewer, Mark A.; Dempsey, Robert J.; Varghese, Tomy

    2008-11-01

    In this paper, we explore two parameters or strain indices related to plaque deformation during the cardiac cycle, namely, the maximum accumulated axial strain in plaque and the relative lateral shifts between plaque and vessel wall under in vivo clinical ultrasound imaging conditions for possible identification of vulnerable plaque. These strain indices enable differentiation between calcified and lipidic plaque tissue utilizing a new perspective based on the stiffness and mobility of the plaque. In addition, they also provide the ability to distinguish between softer plaques that undergo large deformations during the cardiac cycle when compared to stiffer plaque tissue. Soft plaques that undergo large deformations over the cardiac cycle are more prone to rupture and to release micro-emboli into the cerebral bloodstream. The ability to identify vulnerable plaque, prone to rupture, would significantly enhance the clinical utility of this method for screening patients. We present preliminary in vivo results obtained from ultrasound radio frequency data collected over 16 atherosclerotic plaque patients before these patients undergo a carotid endarterectomy procedure. Our preliminary in vivo results indicate that the maximum accumulated axial strain over a cardiac cycle and the maximum relative lateral shift or displacement of the plaque are useful strain indices that provide differentiation between soft and calcified plaques.

  11. Ultraviolet Phototherapy Management of Moderate-to-Severe Plaque Psoriasis

    PubMed Central

    2009-01-01

    Executive Summary Objective The purpose of this evidence based analysis was to determine the effectiveness and safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis. Research Questions The specific research questions for the evidence review were as follows: What is the safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis? What is the effectiveness of ultraviolet phototherapy for moderate-to-severe plaque psoriasis? Clinical Need: Target Population and Condition Psoriasis is a common chronic, systemic inflammatory disease affecting the skin, nails and occasionally the joints and has a lifelong waning and waxing course. It has a worldwide occurrence with a prevalence of at least 2% of the general population, making it one of the most common systemic inflammatory diseases. The immune-mediated disease has several clinical presentations with the most common (85% - 90%) being plaque psoriasis. Characteristic features of psoriasis include scaling, redness, and elevation of the skin. Patients with psoriasis may also present with a range of disabling symptoms such as pruritus (itching), pain, bleeding, or burning associated with plaque lesions and up to 30% are classified as having moderate-to-severe disease. Further, some psoriasis patients can be complex medical cases in which diabetes, inflammatory bowel disease, and hypertension are more likely to be present than in control populations and 10% also suffer from arthritis (psoriatic arthritis). The etiology of psoriasis is unknown but is thought to result from complex interactions between the environment and predisposing genes. Management of psoriasis is related to the extent of the skin involvement, although its presence on the hands, feet, face or genitalia can present challenges. Moderate-to-severe psoriasis is managed by phototherapy and a range of systemic agents including traditional immunosuppressants such as methotrexate and cyclospsorin. Treatment with modern immunosuppressant agents known as biologicals, which more specifically target the immune defects of the disease, is usually reserved for patients with contraindications and those failing or unresponsive to treatments with traditional immunosuppressants or phototherapy. Treatment plans are based on a long-term approach to managing the disease, patient’s expectations, individual responses and risk of complications. The treatment goals are several fold but primarily to: 1) improve physical signs and secondary psychological effects, 2) reduce inflammation and control skin shedding, 3) control physical signs as long as possible, and to 4) avoid factors that can aggravate the condition. Approaches are generally individualized because of the variable presentation, quality of life implications, co-existent medical conditions, and triggering factors (e.g. stress, infections and medications). Individual responses and commitments to therapy also present possible limitations. Phototherapy Ultraviolet phototherapy units have been licensed since February 1993 as a class 2 device in Canada. Units are available as hand held devices, hand and foot devices, full-body panel, and booth styles for institutional and home use. Units are also available with a range of ultraviolet A, broad and narrow band ultraviolet B (BB-UVB and NB-UVB) lamps. After establishing appropriate ultraviolet doses, three-times weekly treatment schedules for 20 to 25 treatments are generally needed to control symptoms. Evidence-Based Analysis Methods The literature search strategy employed keywords and subject headings to capture the concepts of 1) phototherapy and 2) psoriasis. The search involved runs in the following databases: Ovid MEDLINE (1996 to March Week 3 2009), OVID MEDLINE In-Process and Other Non-Indexed Citations, EMBASE (1980 to 2009 Week 13), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination/International Agency for Health Technology Assessment. Parallel search strategies were developed for the remaining databases. Search results were limited to human and English-language

  12. Cerebral Embolism during Carotid Artery Stenting: Role of Carotid Plaque Echolucency

    Microsoft Academic Search

    Michael Rosenkranz; Oliver Wittkugel; Christian Waiblinger; Götz Thomalla; Anna Krützelmann; Stefanie Havemeister; Hermann Zeumer; Christian Gerloff; Jens Fiehler

    2009-01-01

    Background: Carotid artery stenting (CAS) is associated with the risk of intraprocedural stroke. A better understanding of specific risk factors could help to improve the procedure and to reduce the overall risk of CAS. We addressed the role of carotid plaque echolucency as potential risk factor for cerebral embolism during CAS. Methods: We prospectively evaluated carotid plaque echolucency by use

  13. Human Root Caries: Microbiota in Plaque Covering Sound, Carious and Arrested Carious Root Surfaces

    Microsoft Academic Search

    P. Schüpbach; V. Osterwalder; B. Guggenheim

    1995-01-01

    The plaque microbiota covering sound or carious root surfaces were studied and compared with that covering arrested root caries lesions. From each of these categories five extracted teeth were examined. The experimental design of the study allowed us to relate the qualitative and quantitative microbial composition to the degree of integrity of the root surface. Plaque was sampled by a

  14. Proton-induced X-ray emission analysis of atherosclerotic plaques of the carotid bifurcation.

    PubMed

    Peltomaa, M; Mattila, K; Wolf, J; Hyvönen-Dabek, M

    1992-09-01

    The trace elements of both calcified atherosclerotic plaques and plaque-free vessel walls of the carotid bifurcation from 31 autopsies were investigated using the proton-induced X-ray emission (PIXE) method. The trace elements studied were phosphorus (P), calcium (Ca), chrome (Cr), iron (Fe), copper (Cu), zinc (Zn), lead (Pb), selenium (Se), bromine (Br), strontium (Sr), and rubidium (Rb). All samples contained Fe and Zn. Mercury (Hg) was not detected in any of the samples studied. All plaque-free samples contained Cu and almost all Br and Ca, none Sr. All calcified atherosclerotic plaques contained Ca and almost all Br and Sr. The relative levels of Ca were higher in the calcified plaques than in the plaque-free vessel walls. The relative value of Ca in calcified and uncalcified samples was greatest in the group who had died because of cardiovascular disorders and smallest in the group who had died from other causes. There was a strong positive correlation between the Ca and Sr of the plaque samples and between the P and Br of the plaque-free samples. PMID:1384615

  15. Influence of Electrode Position on the Characterization of Artery Stenotic Plaques by Using Impedance Catheter

    Microsoft Academic Search

    Sungbo Cho; Hagen Thielecke

    2006-01-01

    Use of balloon impedance catheters (BIC) for the characterization of plaques in vessels can support an optimal medical treatment of plaques. The sensitivity of impedance diagnoses with BIC is related with the distribution of electric fields determined by the electrode configuration. Using the three-dimensional finite element method (FEM) simulation, it was estimated how the relative positions of electrode array to

  16. Segmentation of wall and plaque in in vitro vascular MR images

    Microsoft Academic Search

    Fuxing Yang; Gerhard Holzapfel; Christian Schulze-Bauer; Rudolf Stollberger; Daniel Thedens; Lizann Bolinger; Alan Stolpen; Milan Sonka

    2003-01-01

    Atherosclerosis leads to heart attack and stroke, which are major killers in the western world. These cardiovascular events frequently result from local rupture of vulnerable atherosclerotic plaque. Non- invasive assessment of plaque vulnerability would dramatically change the way in which atherosclerotic disease is diagnosed, monitored, and treated. In this paper, we report a computerized method for seg- mentation of arterial

  17. Impact of Preoperative Dental Plaque Culture for Predicting Postoperative Pneumonia in Esophageal Cancer Patients

    Microsoft Academic Search

    Yasunori Akutsu; Hisahiro Matsubara; Shinichi Okazumi; Hideaki Shimada; Kiyohiko Shuto; Toru Shiratori; Takenori Ochiai

    2008-01-01

    Background\\/Aims: In esophageal cancer patients, postoperative pneumonia frequently occurs. In the oral cavity, dental plaque is a major reservoir of bacteria, and it is possible that oral bacteria are aspirated into the upper respiratory tract after esophagectomy. We evaluated the interaction between preoperative dental plaque and postoperative pneumonia in patients undergoing esophagectomy. Patients and Methods: Thirty-nine patients with thoracic esophageal

  18. A Catheter-Based Intravascular Radiation Detector ofVulnerablePlaques

    Microsoft Academic Search

    Ryohei Hosokawa; Naoshige Kambara; Muneo Ohba; Takahiro Mukai; Mikako Ogawa; Hiroshi Motomura; Noriaki Kume; Hideo Saji; Toru Kit; Ryuji Nohara

    Detection of vulnerable plaques before rupture is important in preventing acute coronary events such as myocardial infarction. Althoughtherapeuticstrategiessuchaspercutaneoustranslumi- nal coronary angioplasty appear to prevent coronary occlusion and consequently may lead to improved prognosis in these pa- tients, a method of detecting vulnerable plaques has not been established. A nuclear method that uses an intravascular radia- tion detector (IVRD) with the

  19. Effects of dental plaque antiseptic decontamination on bacterial colonization and nosocomial infections in critically ill patients

    Microsoft Academic Search

    F. Fourrier; E. Cau-Pottier; H. Boutigny; M. Roussel-Delvallez; M. Jourdain; C. Chopin

    2000-01-01

    Objectives: To document in intensive care unit (ICU) patients the effect of dental plaque antiseptic decontamination on the occurrence of plaque colonization by aerobic nosocomial pathogens and nosocomial infections. Design: Single-blind randomized comparative study. Setting: A 16-bed adult intensive care unit in a university hospital. Patients: Patients consecutively admitted in the ICU with a medical condition suggesting an ICU stay

  20. Measurement of density and calcium in human atherosclerotic plaque and implications for arterial brachytherapy

    Microsoft Academic Search

    David A. Rahdert; William L. Sweet; Fermin O. Tio; Christian Janicki; Dennis M. Duggan

    1999-01-01

    Purpose. To measure density of arterial plaque specimens for purposes of improving calculation of intravascular radiation dose.Methods and Materials. In the described technique, the mass of the specimen submerged in water is compared with its mass in air. Thirty-three plaque specimens harvested from cadavers and subsequently histologically classified (18 coronary, 15 noncoronary) were subjected to density measurement, and were also

  1. Determinants of the fluorescence emission spectrum of atheromatous plaques treated with haematoporphyrin in vitro

    Microsoft Academic Search

    David Kessel; Ramon Berguer

    1990-01-01

    Studies were carried out on atheromatous plaques which had been incubated with the fluorescent dye haematoporphyrin. By varying the wavelength of excitation, it was possible to obtain fluorescence signals from different depths in plaque, since enhanced tissue penetration occurs when the wavelength of exciting light is increased. Moreover, the presence of ulcerated regions altered both excitation and emission spectra. These

  2. Identification of Genes Potentially Involved in Rupture of Human Atherosclerotic Plaques

    Microsoft Academic Search

    Birgit C. G. Faber; Kitty B. J. M. Cleutjens; Ron L. J. Niessen; Petra L. J. W. Aarts; Wendy Boon; Andrew S. Greenberg; Jan H. M. Tordoir; Mat J. A. P. Daemen

    2010-01-01

    Although rupture of an atherosclerotic plaque is the major cause of acute vascular occlusion, the exact molecular mechanisms underlying this process are still poorly understood. In this study, we used suppression subtractive hybridization to make an inventory of genes that are differentially expressed in whole-mount human stable and ruptured plaques. Two libraries were generated, one containing 3000 clones upregulated and

  3. [Vascular Calcification - Pathological Mechanism and Clinical Application - . The significance of arterial calcification in unstable plaques].

    PubMed

    Inaba, Mayumi; Ueda, Makiko

    2015-01-01

    Plaque rupture or erosion with subsequent thrombus formation is the principal mechanism underlying the sudden onset of acute coronary syndromes. Plaque inflammation and increased oxidative stress play important roles in the pathogenesis of plaque destabilization. Macrophages, T lymphocytes, and neutrophils are the dominant types of inflammatory cells at human coronary unstable plaques, such as ruptured plaques or eroded plaques. Calcification is a common finding in human atherosclerotic lesions, and arterial calcification is generally classified into calcification within an atherosclerotic plaque, and Mönckeberg's medial calcific sclerosis characterized by calcific deposits within the media of small and medium-sized muscular arteries. It has been reported that a spotty pattern of calcification is associated with coronary unstable ruptured plaques in patients with acute myocardial infarction. Patients undergoing hemodialysis (HD) have a high prevalence of arterial calcification and cardiovascular events. We recently demonstrated that plasma oxidized low density lipoprotein (LDL) levels significantly increased after a single HD session. This HD session-related increase in plasma oxidized LDL levels could contribute to the progression and acceleration of atherosclerosis and arterial calcification, leading to the development of cardiovascular events in HD patients. PMID:25926571

  4. Shear wave elastography plaque characterization with mechanical testing validation: a phantom study

    NASA Astrophysics Data System (ADS)

    Widman, E.; Maksuti, E.; Larsson, D.; Urban, M. W.; Bjällmark, A.; Larsson, M.

    2015-04-01

    Determining plaque vulnerability is critical when selecting the most suitable treatment for patients with atherosclerotic plaque. Currently, clinical non-invasive ultrasound-based methods for plaque characterization are limited to visual assessment of plaque morphology and new quantitative methods are needed. In this study, shear wave elastography (SWE) was used to characterize hard and soft plaque mimicking inclusions in six common carotid artery phantoms by using phase velocity analysis in static and dynamic environments. The results were validated with mechanical tensile testing. In the static environment, SWE measured a mean shear modulus of 5.8? ± ?0.3?kPa and 106.2? ± ?17.2?kPa versus 3.3? ± ?0.5?kPa and 98.3? ± ?3.4?kPa measured by mechanical testing in the soft and hard plaques respectively. Furthermore, it was possible to measure the plaques’ shear moduli throughout a simulated cardiac cycle. The results show good agreement between SWE and mechanical testing and indicate the possibility for in vivo arterial plaque characterization using SWE.

  5. Senile plaques stimulate microglia to release a neurotoxin found in Alzheimer brain

    Microsoft Academic Search

    Dana Giulian; Lanny J. Haverkamp; Jun Li; William L. Karshin; Jenny Yu; Donald Tom; Xia Li; Joel B. Kirkpatrick

    1995-01-01

    Senile plaques found in the brains of patients with Alzheimer's disease (AD) are surrounded by clusters of reactive microglia. Isolated human microglia placed in contact with plaques in vitro are activated to release a factor which is toxic to neurons. This same neurotoxin is found in AD brain tissue and causes damage to pyramidal neurons in vivo when infused into

  6. Effect of Two Antibacterial Mouth Sprays and Dentifrices on Dental Plaque and Gingivitis in Beagle Dogs

    Microsoft Academic Search

    F. H. Compton; G. S. Beagrie; Robert Chernecky; Kirsten Glasser

    1979-01-01

    Plaque inhibition by dilute mouth sprays and dentifrices containing benzethonium chloride and chlorhexidine gluconate was compared in beagle dogs. Agents with chlorhexidine gluconate produced less plaque than their benzethonium chloride or placebo counterparts, but the differences were not significant when compared to mean control scores registered during interexperimental recovery periods.

  7. Intracranial Plaque Enhancement in Patients with Cerebrovascular Events on High-Spatial-Resolution MR Images

    PubMed Central

    Qiao, Ye; Zeiler, Steven R.; Mirbagheri, Saeedeh; Leigh, Richard; Urrutia, Victor; Wityk, Robert

    2014-01-01

    Purpose To characterize intracranial plaque inflammation in vivo by using three-dimensional (3D) high-spatial-resolution contrast material–enhanced black-blood (BB) magnetic resonance (MR) imaging and to investigate the relationship between intracranial plaque inflammation and cerebrovascular ischemic events. Materials and Methods The study was approved by the institutional review board and was HIPAA compliant. Twenty-seven patients (19 men; mean age, 56.8 years ± 12.4 [standard deviation]) with cerebrovascular ischemic events (acute stroke, n = 20; subacute stroke, n = 2; chronic stroke, n = 3; transient ischemic attack, n = 2) underwent 3D time-of-flight MR angiography and contrast-enhanced BB 3-T MR imaging for intracranial atherosclerotic disease. Each identified plaque was classified as either culprit (the only or most stenotic lesion upstream from a stroke), probably culprit (not the most stenotic lesion upstream from a stroke), or nonculprit (not within the vascular territory of a stroke). Plaque contrast enhancement was categorized on BB MR images (grade 0, enhancement less than or equal to that of normal arterial walls seen elsewhere; grade 1, enhancement greater than grade 0 but less than that of the pituitary infundibulum; grade 2, enhancement greater than or equal to that of the pituitary infundibulum), and degree of contrast enhancement was calculated. Associations of the likelihood of being a culprit lesion with both plaque contrast enhancement and plaque thickness were estimated with ordinal logistic regression. Results Seventy-eight plaques were identified in 20 patients with acute stroke (21 [27%] culprit, 12 [15%] probably culprit, and 45 [58%] nonculprit plaques). In these patients, grade 2 contrast enhancement was associated with culprit plaques (odds ratio 34.6; 95% confidence interval: 4.5, 266.5 compared with grade 0) when adjusted for plaque thickness. Grade 0 was observed in only nonculprit plaques. Culprit plaques had a higher degree of contrast enhancement than did nonculprit plaques (25.9% ± 13.4 vs 13.6% ± 12.3, P = .003). Conclusion Contrast enhancement of intracranial atherosclerotic plaque is associated with its likelihood to have caused a recent ischemic event and may serve as a marker of its stability, thereby providing important insight into stroke risk. © RSNA, 2014 Online supplemental material is available for this article. PMID:24475850

  8. A Negative Correlation between Human Carotid Atherosclerotic Plaque Progression and Plaque Wall Stress: In Vivo MRI-Based 2D/3D FSI Models

    PubMed Central

    Tang, Dalin; Yang, Chun; Mondal, Sayan; Liu, Fei; Canton, Gador; Hatsukami, Thomas S.; Yuan, Chun

    2008-01-01

    It is well accepted that atherosclerosis initiation and progression correlate positively with low and oscillating flow wall shear stresses (FSS). However, this mechanism cannot explain why advanced plaques continue to grow under elevated FSS conditions. In vivo magnetic resonance imaging (MRI)-based 2D/3D multi-component models with fluid-structure interactions (FSI, 3D only) for human carotid atherosclerotic plaques were introduced to quantify correlations between plaque progression measured by wall thickness increase (WTI) and plaque wall (structure) stress (PWS) conditions. A histologically validated multi-contrast MRI protocol was used to acquire multi-year in vivo MRI images. Our results using 2D models (200–700 data points/patient) indicated that 18 out of 21 patients studied showed significant negative correlation between WTI and PWS at time 2 (T2). The 95% confidence interval for the Pearson correlation coefficient is (?0.443, ?0.246), p < 0.0001. Our 3D FSI model supported the 2D correlation results and further indicated that combining both plaque structure stress and flow shear stress gave better approximation results (PWS, T2: R2 = 0.279; FSS, T1: R2 = 0.276; Combining both: R2 = 0.637). These pilot studies suggest that both lower PWS and lower FSS may contribute to continued plaque progression and should be taken into consideration in future investigations of diseases related to atherosclerosis. PMID:18191138

  9. Age differentiation of rat smooth muscle cells : altered proliferation profile, cellular changes, and implications for atherosclerotic plaque destabilization

    E-print Network

    Huang, Chen-Wen, 1979-

    2004-01-01

    Clinical evidence has shown that the elderly are at a higher risk for atherosclerotic plaque destabilization. The effect of aging on smooth muscle cells, a major cell type in the plaque, is central to the process of disease ...

  10. Lipid composition in atheromatous plaque: evaluation of the lipid three-phase percentage.

    PubMed

    Marinello, Enrico; Setacci, Carlo; Giubbolini, Michele; Cinci, Giuliano; Frosi, Barbara; Porcelli, Brunetta; Terzuoli, Lucia

    2003-05-01

    There is a renewed interest in the study of plaque lipid composition because it is recognized that it, rather than the luminal narrowing, influences the plaque stability and determines patient symptoms. At this purpose, we quantitatively evaluated in the carotid plaque of different categories of patients the expression of triglycerides, phospholipids, cholesterol, free cholesterol, esters of cholesterol, and the percentages of the three-phases (cholesterol, esters of cholesterol, phospholipids) by using the "Roozeboom triangle". Significant differences in the content of specific lipid and the percentage of the three-phases were detected among the different types of plaque evaluated in this study. The analysis of the three-phases by "Roozeboom triangle" may open a new approach in the study of atheromatous plaque and give new information on development of the disease. PMID:12679186

  11. Coronary Plaque Boundary Enhancement in IVUS Image by Using a Modified Perona-Malik Diffusion Filter

    PubMed Central

    Anam, S.; Uchino, E.; Suetake, N.

    2014-01-01

    We propose a modified Perona-Malik diffusion (PMD) filter to enhance a coronary plaque boundary by considering the conditions peculiar to an intravascular ultrasound (IVUS) image. The IVUS image is commonly used for a diagnosis of acute coronary syndrome (ACS). The IVUS image is however very grainy due to heavy speckle noise. When the normal PMD filter is applied for speckle noise reduction in the IVUS image, the coronary plaque boundary becomes vague. For this problem, we propose a modified PMD filter which is designed in special reference to the coronary plaque boundary detection. It can then not only reduce the speckle noise but also enhance clearly the coronary plaque boundary. After applying the modified PMD filter to the IVUS image, the coronary plaque boundaries are successfully detected further by applying the Takagi-Sugeno fuzzy model. The accuracy of the proposed method has been confirmed numerically by the experiments. PMID:25506357

  12. A finite element study of balloon expandable stent for plaque and arterial wall vulnerability assessment

    NASA Astrophysics Data System (ADS)

    Karimi, Alireza; Navidbakhsh, Mahdi; Razaghi, Reza

    2014-07-01

    The stresses induced within plaque tissues and arterial layers during stent expansion inside an atherosclerotic artery can be exceeded from the yield stresses of those tissues and, consequently, lead to plaque or arterial layer rupture. The distribution and magnitude of the stresses in each component involved in stenting might be clearly different for different plaque types and different arterial layers. In this study, a nonlinear finite element simulation was employed to investigate the effect of plaque composition (calcified, cellular, and hypocellular) on the stresses induced in the arterial layers (intima, media, and adventitia) during implantation of a balloon expandable coronary stent into a stenosed artery. The atherosclerotic artery was assumed to consist of a plaque and normal/healthy arterial tissues on its outer side. The results indicated a significant influence of plaque types on the maximum stresses induced within the plaque wall and arterial layers during stenting but not when computing maximum stress on the stent. The stress on the stiffest calcified plaque wall was in the fracture level (2.38 MPa), whereas cellular and hypocellular plaques remain stable owing to less stress on their walls. Regardless of plaque types, the highest von Mises stresses were observed on the stiffest intima layer, whereas the lowest stresses were seen to be located in less stiff media layer. The computed stresses on the intima layer were found to be high enough to initiate a rupture in this stiff layer. These findings suggest a higher risk of arterial vascular injury for the intima layer, while a lower risk of arterial injury for the media and adventitia layers.

  13. Automated Detection Framework of the Calcified Plaque with Acoustic Shadowing in IVUS Images

    PubMed Central

    Liu, Xin; Huang, Wenhua; Zhang, Heye; Tan, Ning; Hau, William Kongto; Zhang, Yuan-Ting; Liu, Huafeng

    2014-01-01

    Intravascular Ultrasound (IVUS) is one ultrasonic imaging technology to acquire vascular cross-sectional images for the visualization of the inner vessel structure. This technique has been widely used for the diagnosis and treatment of coronary artery diseases. The detection of the calcified plaque with acoustic shadowing in IVUS images plays a vital role in the quantitative analysis of atheromatous plaques. The conventional method of the calcium detection is manual drawing by the doctors. However, it is very time-consuming, and with high inter-observer and intra-observer variability between different doctors. Therefore, the computer-aided detection of the calcified plaque is highly desired. In this paper, an automated method is proposed to detect the calcified plaque with acoustic shadowing in IVUS images by the Rayleigh mixture model, the Markov random field, the graph searching method and the prior knowledge about the calcified plaque. The performance of our method was evaluated over 996 in-vivo IVUS images acquired from eight patients, and the detected calcified plaques are compared with manually detected calcified plaques by one cardiology doctor. The experimental results are quantitatively analyzed separately by three evaluation methods, the test of the sensitivity and specificity, the linear regression and the Bland-Altman analysis. The first method is used to evaluate the ability to distinguish between IVUS images with and without the calcified plaque, and the latter two methods can respectively measure the correlation and the agreement between our results and manual drawing results for locating the calcified plaque in the IVUS image. High sensitivity (94.68%) and specificity (95.82%), good correlation and agreement (>96.82% results fall within the 95% confidence interval in the Student t-test) demonstrate the effectiveness of the proposed method in the detection of the calcified plaque with acoustic shadowing in IVUS images. PMID:25372784

  14. Efficacy of essential oil mouthwash with and without alcohol: a 3-Day plaque accumulation model

    PubMed Central

    2011-01-01

    Background The aim of this study was to evaluate the antiplaque effect of a new alcohol free essential oil mouthwash with respect to a control of an essential oil with alcohol mouthwash, using an in vivo plaque regrowth model of 3-days. Methods The study was designed as a double-masked, randomized, crossover clinical trial, involving 30 volunteers to compare two different essential oil containing mouthwashes, during a 3-day plaque accumulation model. After receiving a thorough professional prophylaxis at the baseline, over the next 3-days each volunteer refrained from all oral hygiene measures and had two daily rinses with 20 ml of the test mouthwash (alcohol free essential oil) or the control mouthwash (essential oil with alcohol). At the end of the each experimental period, plaque was assessed and the panelists filled out a questionnaire. Each subject underwent a 14 days washout period and there was a second allocation. Results The essential oil mouthwash with ethanol shows a better inhibitory effect of plaque regrowth in 3-days than the mouthwash test with only essential oil in the whole mouth (plaque index = 2.18 against 2.46, respectively, p < 0.05); for the lower jaw (plaque index = 2.28 against 2.57, respectively, p < 0.05); for the upper jaw (plaque index = 2.08 against 2.35, respectively, p < 0.05); for the incisors (plaque index = 1.93 against 2.27, respectively, p < 0.05); and the canines (plaque index = 1.99 against 2.47, respectively, p < 0.05). Conclusion The essential oil containing mouthwash without alcohol seems to have a less inhibiting effect on the plaque regrowth than the traditional alcoholic solution. Trial Registration ClinicalTrials.gov NCT01411618 PMID:22171999

  15. The influence of inaccuracies in carotid MRI segmentation on atherosclerotic plaque stress computations.

    PubMed

    Nieuwstadt, Harm A; Speelman, Lambert; Breeuwer, Marcel; van der Lugt, Aad; van der Steen, Anton F W; Wentzel, Jolanda J; Gijsen, Frank J H

    2014-02-01

    Biomechanical finite element analysis (FEA) based on in vivo carotid magnetic resonance imaging (MRI) can be used to assess carotid plaque vulnerability noninvasively by computing peak cap stress. However, the accuracy of MRI plaque segmentation and the influence this has on FEA has remained unreported due to the lack of a reliable submillimeter ground truth. In this study, we quantify this influence using novel numerical simulations of carotid MRI. Histological sections from carotid plaques from 12 patients were used to create 33 ground truth plaque models. These models were subjected to numerical computer simulations of a currently used clinically applied 3.0?T T1-weighted black-blood carotid MRI protocol (in-plane acquisition voxel size of 0.62?×?0.62 mm2) to generate simulated in vivo MR images from a known underlying ground truth. The simulated images were manually segmented by three MRI readers. FEA models based on the MRI segmentations were compared with the FEA models based on the ground truth. MRI-based FEA model peak cap stress was consistently underestimated, but still correlated (R) moderately with the ground truth stress: R?=?0.71, R?=?0.47, and R?=?0.76 for the three MRI readers respectively (p?plaque stretch was underestimated as well. The peak cap stress in thick-cap, low stress plaques was substantially more accurately and precisely predicted (error of -12?±?44?kPa) than the peak cap stress in plaques with caps thinner than the acquisition voxel size (error of -177?±?168?kPa). For reliable MRI-based FEA to compute the peak cap stress of carotid plaques with thin caps, the current clinically used in-plane acquisition voxel size (?0.6?mm) is inadequate. FEA plaque stress computations would be considerably more reliable if they would be used to identify thick-cap carotid plaques with low stresses instead. PMID:24317274

  16. CycloOxygenase2 –765G > C Promoter Variants Are Associated with Lower Carotid Plaque Echogenicity in Japanese

    Microsoft Academic Search

    Shigetaka Furukado; Manabu Sakaguchi; Hiroshi Yamagami; Yoshiki Yagita; Taku Hoshi; Yuko Abe; Hidetaka Hougaku; Masatsugu Hori; Saburo Sakoda; Kazuo Kitagawa

    2009-01-01

    Background and Purpose: Recent studies revealed that inflammation contributes to plaque instability. Cyclo-oxygenase (COX)-2 is one of the key enzymes in plaque inflammation. We examined the relation between a polymorphism in the COX-2 gene and carotid plaque echogenicity in patients with high risk of cerebrovascular disease to evaluate the involvement of COX-2 in plaque instability. Methods: The study comprised 469

  17. Plaque morphea with neurological involvement—an extraordinary uncommon presentation.

    PubMed

    Rosario, Cristina; Garelick, Daniela; Greenberg, Gahl; Chapman, Joab; Shoenfeld, Yehuda; Langevitz, Pnina

    2015-03-01

    Localized scleroderma is traditionally considered to be limited to the skin, subcutaneous tissue, underlying bone, and in the craniofacial subtype, also nervous system involvement. However, recent studies have also described other systemic manifestations in these patients. Despite many reports of neurological involvement in patients with the craniofacial linear localized scleroderma, it is extremely rare in patients with the other subtypes of localized scleroderma. Here, we report an extraordinary case of localized scleroderma en plaque (classic morphea), located to the upper trunk and neck, associated with neurological manifestations presented as seizures. Magnetic resonance imaging of the brain showed focal lesions on the contralateral side to the skin involvement. This case is extremely relevant not only due to its rarity, but also because it supports the idea that the pathogenesis of the localized scleroderma is related to a systemic autoimmune process. PMID:24352753

  18. Identification of Atherosclerotic Plaques in Carotid Artery by Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Rocha, Rick; Villaverde, Antonio Balbin; Silveira, Landulfo; Costa, Maricília Silva; Alves, Leandro Procópio; Pasqualucci, Carlos Augusto; Brugnera, Aldo

    2008-04-01

    The aim of this work was to identify the presence of atherosclerotic plaques in carotid artery using the Fluorescence Spectroscopy. The most important pathogeny in the cardiovascular disorders is the atherosclerosis, which may affect even younger individuals. With approximately 1.2 million heart attacks and 750,000 strokes afflicting an aging American population each year, cardiovascular disease remains the number one cause of death. Carotid artery samples were obtained from the Autopsy Service at the University of São Paulo (São Paulo, SP, Brazil) taken from cadavers. After a histopathological analysis the 60 carotid artery samples were divided into two groups: normal (26) and atherosclerotic plaques (34). Samples were irradiated with the wavelength of 488 nm from an Argon laser. A 600 ?m core optical fiber, coupled to the Argon laser, was used for excitation of the sample, whereas another 600 optical fiber, coupled to the spectrograph entrance slit, was used for collecting the fluorescence from the sample. Measurements were taken at different points on each sample and then averaged. Fluorescence spectra showed a single broad line centered at 549 nm. The fluorescence intensity for each sample was calculated by subtracting the intensity at the peak (550 nm) and at the bottom (510 nm) and then data were statistically analyzed, looking for differences between both groups of samples. ANOVA statistical test showed a significant difference (p<0,05) between both types of tissues, with regard to the fluorescence peak intensities. Our results indicate that this technique could be used to detect the presence of the atherosclerotic in carotid tissue.

  19. Association between Randall’s plaque and calcifying nanoparticles

    PubMed Central

    Çiftçio?lu, Neva; Vejdani, Kaveh; Lee, Olivia; Mathew, Grace; Aho, Katja M; Kajander, E Olavi; McKay, David S; Jones, Jeffrey A; Stoller, Marshall L

    2008-01-01

    Objectives Randall initially described calcified subepithelial papillary plaques, which he hypothesized as nidi for urinary calculi. The discovery of calcifying nanoparticles (CNP), also referred to as nanobacteria, in calcified soft tissues has raised another hypothesis about their possible involvement in urinary stone formation. This research is the first attempt to investigate the potential association of these two hypotheses. Methods We collected renal papilla and blood samples from 17 human patients who had undergone laparoscopic nephrectomy. Immunohistochemical staining (IHS) was applied using monoclonal antibody (mAb) against CNP. Homogenized papillary tissues and serum samples were cultured for CNP. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were performed on papillary samples. Serum samples were tested for CNP antigen and antibody with enzyme-linked immunosorbent assay (ELISA). Results Randall’s plaques (RP) were visible on gross inspection in 11 out of 17 samples. IHS was positive for CNP antigen in 8 of the visually positive samples, but in only 1 of the remaining samples. SEM revealed spherical apatite-formations in 14 samples confirmed by EDS analysis. In cultures, all serum samples and 13 tissue homogenates grew CNP. In ELISA, 14 samples were positive for CNP-antigen and 11 samples were positive for CNP-antibody. Conclusion There was evidence of a link between detection of CNP and presence of RP. Although causality was not demonstrated, these results suggest that further studies with negative control samples should be made to explore the etiology of RP formation, thus leading to a better understanding of the pathogenesis of stone formation. PMID:18488421

  20. Meshless Generalized Finite Difference Method and Human Carotid Atherosclerotic Plaque Progression Simulation Using Multi-Year MRI Patient-Tracking Data

    PubMed Central

    Yang, Chun; Tang, Dalin; Yuan, Chun; Kerwin, William; Liu, Fei; Canton, Gador; Hatsukami, Thomas S.; Atluri, Satya

    2009-01-01

    Atherosclerotic plaque rupture and progression have been the focus of intensive investigations in recent years. Plaque rupture is closely related to most severe cardiovascular syndromes such as heart attack and stroke. A computational procedure based on meshless generalized finite difference (MGFD) method and serial magnetic resonance imaging (MRI) data was introduced to quantify patient-specific carotid atherosclerotic plaque growth functions and simulate plaque progression. Participating patients were scanned three times (T1, T2, and T3, at intervals of about 18 months) to obtain plaque progression data. Vessel wall thickness (WT) changes were used as the measure for plaque progression. Since there was insufficient data with the current technology to quantify individual plaque component growth, the whole plaque was assumed to be uniform, homogeneous, hyperelastic, isotropic and nearly incompressible. The linear elastic model was used. The 2D plaque model was discretized and solved using a meshless generalized finite difference (GFD) method. Starting from the T2 plaque geometry, plaque progression was simulated by solving the solid model and adjusting wall thickness using plaque growth functions iteratively until T3 is reached. Numerically simulated plaque progression agreed very well with actual plaque geometry at T3 given by MRI data. We believe this is the first time plaque progression simulation based on multi-year patient-tracking data was reported. Serial MRI-based progression simulation adds time dimension to plaque vulnerability assessment and will improve prediction accuracy for potential plaque rupture risk. PMID:19774222

  1. Molecular Imaging of Low-density Lipoprotein in Human Coronary Plaques by Color Fluorescent Angioscopy and Microscopy

    PubMed Central

    Uchida, Yasumi; Maezawa, Yuko; Uchida, Yasuto; Hiruta, Nobuyuki; Shimoyama, Ei

    2012-01-01

    Objectives Low-density lipoprotein (LDL) is an important risk factor for coronary artery disease. However, its localization in human coronary plaques is not well understood. The present study was performed to visualize LDL in human coronary artery wall. Methods (1) The fluorescence characteristic of LDL was investigated by color fluorescent microscopy (CFM) with excitation at 470-nm and emission at 515-nm using Nile blue dye (NB) as a biomarker. (2) Native LDL in 40 normal segments, 42 white plaques and 35 yellow plaques (20 with necrotic core) of human coronary arteries was investigated by color fluorescent angioscopy (CFA) and CFM. Results (1) NB elicited a brown, golden and red fluorescence characteristic of LDL, apolipoprotein B-100, and lysophosphatidylcholine/triglyceride, respectively. (2) The % incidence of LDL in normal segments, white, and yellow plaques was 25, 38 and 14 by CFA and 42, 42 and 14 by CFM scan of their luminal surface, respectively, indicating lower incidence (p<0.05) of LDL in yellow plaques than white plaques, and no significant differences in detection sensitivity between CFA and CFM. By CFM transected surface scan, LDL deposited more frequently and more diffusely in white plaques and yellow plaques without necrotic core (NC) than normal segments and yellow plaques with NC. LDL was localized to fibrous cap in yellow plaques with NC. Co-deposition of LDL with other lipid components was observed frequently in white plaques and yellow plaques without NC. Conclusions (1) Taken into consideration of the well-known process of coronary plaque growth, the results of the present study suggest that LDL begins to deposit before plaque formation; increasingly deposits with plaque growth, often co-depositing with other lipid components; and disappears after necrotic core formation. (2) CFA is feasible for visualization of LDL in human coronary artery wall. PMID:23209809

  2. Viral Concentration Determination Through Plaque Assays: Using Traditional and Novel Overlay Systems

    PubMed Central

    Baer, Alan; Kehn-Hall, Kylene

    2015-01-01

    Plaque assays remain one of the most accurate methods for the direct quantification of infectious virons and antiviral substances through the counting of discrete plaques (infectious units and cellular dead zones) in cell culture. Here we demonstrate how to perform a basic plaque assay, and how differing overlays and techniques can affect plaque formation and production. Typically solid or semisolid overlay substrates, such as agarose or carboxymethyl cellulose, have been used to restrict viral spread, preventing indiscriminate infection through the liquid growth medium. Immobilized overlays restrict cellular infection to the immediately surrounding monolayer, allowing the formation of discrete countable foci and subsequent plaque formation. To overcome the difficulties inherent in using traditional overlays, a novel liquid overlay utilizing microcrystalline cellulose and carboxymethyl cellulose sodium has been increasingly used as a replacement in the standard plaque assay. Liquid overlay plaque assays can be readily performed in either standard 6 or 12 well plate formats as per traditional techniques and require no special equipment. Due to its liquid state and subsequent ease of application and removal, microculture plate formats may alternatively be utilized as a rapid, accurate and high throughput alternative to larger scale viral titrations. Use of a non heated viscous liquid polymer offers the opportunity to streamline work, conserves reagents, incubator space, and increases operational safety when used in traditional or high containment labs as no reagent heating or glassware are required. Liquid overlays may also prove more sensitive than traditional overlays for certain heat labile viruses. PMID:25407402

  3. MRI-based biomechanical imaging: initial study on early plaque progression and vessel remodeling

    PubMed Central

    Zheng, Jie; Abendschein, Dana R.; Okamoto, Ruth J.; Yang, Deshan; McCommis, Kyle S.; Misselwitz, Bernd; Gropler, Robert J.; Tang, Dalin

    2010-01-01

    The goal of the study is to develop a noninvasive magnetic resonance imaging (MRI)-based biomechanical imaging technique to address biomechanical pathways of atherosclerotic progression and regression in vivo using a 3D fluid-structure interaction (FSI) model. Initial in vivo study was carried out in an early plaque model in pigs that underwent balloon-overstretch injury to the left carotid arteries. Consecutive MRI scans were performed while the pigs were maintained on high cholesterol (progression) or normal chow (regression), with an injection of a plaque-targeted contrast agent, Gadofluorine M. At the end of study, the specimens of carotid arterial segments were dissected and underwent dedicated mechanical testing to determine their material properties. 3D FSI computational model was applied to calculate structure stress and strain distribution. The plaque structure resembles early plaque with thickened intima. Lower maximal flow shear stress correlates with the growth of plaque volume during progression, but not during regression. In contrast, maximal principle structure stress/stain (stress-P1 and strain-P1) were shown to correlate strongly with the change in the plaque dimension during regression, but moderately during progression. This MRI-based biomechanical imaging method may allow for noninvasive dynamic assessment of local hemodynamic forces on the development of atherosclerotic plaques in vivo. PMID:19559552

  4. Viral concentration determination through plaque assays: using traditional and novel overlay systems.

    PubMed

    Baer, Alan; Kehn-Hall, Kylene

    2014-01-01

    Plaque assays remain one of the most accurate methods for the direct quantification of infectious virons and antiviral substances through the counting of discrete plaques (infectious units and cellular dead zones) in cell culture. Here we demonstrate how to perform a basic plaque assay, and how differing overlays and techniques can affect plaque formation and production. Typically solid or semisolid overlay substrates, such as agarose or carboxymethyl cellulose, have been used to restrict viral spread, preventing indiscriminate infection through the liquid growth medium. Immobilized overlays restrict cellular infection to the immediately surrounding monolayer, allowing the formation of discrete countable foci and subsequent plaque formation. To overcome the difficulties inherent in using traditional overlays, a novel liquid overlay utilizing microcrystalline cellulose and carboxymethyl cellulose sodium has been increasingly used as a replacement in the standard plaque assay. Liquid overlay plaque assays can be readily performed in either standard 6 or 12 well plate formats as per traditional techniques and require no special equipment. Due to its liquid state and subsequent ease of application and removal, microculture plate formats may alternatively be utilized as a rapid, accurate and high throughput alternative to larger scale viral titrations. Use of a non heated viscous liquid polymer offers the opportunity to streamline work, conserves reagents, incubator space, and increases operational safety when used in traditional or high containment labs as no reagent heating or glassware are required. Liquid overlays may also prove more sensitive than traditional overlays for certain heat labile viruses. PMID:25407402

  5. Diffuse Calcifications Protect Carotid Plaques regardless of the Amount of Neoangiogenesis and Related Histological Complications

    PubMed Central

    Vasuri, Francesco; Fittipaldi, Silvia; Pini, Rodolfo; Degiovanni, Alessio; Mauro, Raffaella; D'Errico-Grigioni, Antonia; Faggioli, Gianluca; Stella, Andrea

    2015-01-01

    Background. Neoangiogenesis is crucial in plaque progression and instability. Previous data from our group showed that Nestin-positive intraplaque neovessels correlated with histological complications. The aim of the present work is to evaluate the relationship between neoangiogenesis, plaque morphology, and clinical instability of the plaque. Materials and Methods. Seventy-three patients (53 males and 20 females, mean age 71 years) were consecutively enrolled. Clinical data and 14 histological variables, including intraplaque hemorrhage and calcifications, were collected. Immunohistochemistry for CD34 and Nestin was performed. RT-PCR was performed to evaluate Nestin mRNA (including 5 healthy arteries as controls). Results. Diffusely calcified plaques (13/73) were found predominantly in females (P = 0.017), with a significantly lower incidence of symptoms (TIA/stroke (P = 0.019) than noncalcified plaques but with the same incidence of histological complications (P = 0.156)). Accordingly, calcified and noncalcified plaques showed similar mean densities of positivity for CD34 and Nestin. Nestin density, but not CD34, correlated with the occurrence of intraplaque hemorrhage. Conclusions. Plaques with massive calcifications show the same incidence of histological complications but without influencing symptomatology, especially in female patients, and regardless of the amount of neoangiogenesis. These results can be applied in a future presurgical identification of patients at major risk of developing symptoms. PMID:25883974

  6. Network structure of the mussel plaque and its significance for load bearing and adhesion

    NASA Astrophysics Data System (ADS)

    Filippidi, Emmanouela; Kim, Juntae; Waite, J. Herbert; Helgeson, Matthew; Valentine, Megan T.

    2015-03-01

    Marine mussels attach to rocks, each other, and a variety of surfaces via a flat, wide plaque that is interpenetrated by the collagen fibers of a thin, long thread that connects the plaque to the mussel body. The unusually strong adhesion of the plaque has long been attributed to the molecular design of its adhesive proteins that can form a variety of strong chemical bonds. However, the molecular energies for de-adhesion are orders of magnitude smaller than the macroscopic energies measured. We propose that the mesoscopic design of the plaque is critical in enhancing load bearing and eventually adhesion. We present new results on the structure of the plaque studied via electron microscopy and neutron scattering that exhibit a plaque geometry reminiscent of structural foams. Our studies reveal a collection of pores with an inner network, further connected with an outer network. The final structure can be described by two length scales. A synthetic soft system is constructed in an effort to mimic the two-lengthscale structure of the natural plaques. The structure of the native and synthetic systems is compared with the ultimate goal of evaluating the importance of the mesoscopic structure to mechanics and adhesion. NSF MRSEC IRG-I.

  7. Mechanical, biological and structural characterization of in vitro ruptured human carotid plaque tissue.

    PubMed

    Mulvihill, J J; Cunnane, E M; McHugh, S M; Kavanagh, E G; Walsh, S R; Walsh, M T

    2013-11-01

    Recent experimental studies performed on human carotid plaques have focused on mechanical characterization for the purpose of developing material models for finite-element analysis without quantifying the tissue composition or relating mechanical behaviour to preoperative classification. This study characterizes the mechanical and biological properties of 25 human carotid plaques and also investigates the common features that lead to plaque rupture during mechanical testing by performing circumferential uniaxial tests, Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) on each specimen to relate plaque composition to mechanical behaviour. Mechanical results revealed large variations between plaque specimen behaviour with no correlation to preoperative ultrasound prediction. However, FTIR classification demonstrated a statistically significant relationship between stress and stretch values at rupture and the level of calcification (P=0.002 and P=0.009). Energy-dispersive X-ray spectroscopy was carried out to confirm that the calcium levels observed using FTIR analysis were accurate. This work demonstrates the potential of FTIR as an alternative method to ultrasound forpredicting plaque mechanical behaviour. SEM imaging at the rupture sites of each specimen highlighted voids created by the nodes of calcifications in the tissue structure which could lead to increased vulnerability of the plaque. PMID:23871944

  8. Multi-scale AM-FM motion analysis of ultrasound videos of carotid artery plaques

    NASA Astrophysics Data System (ADS)

    Murillo, Sergio; Murray, Victor; Loizou, C. P.; Pattichis, C. S.; Pattichis, Marios; Barriga, E. Simon

    2012-03-01

    An estimated 82 million American adults have one or more type of cardiovascular diseases (CVD). CVD is the leading cause of death (1 of every 3 deaths) in the United States. When considered separately from other CVDs, stroke ranks third among all causes of death behind diseases of the heart and cancer. Stroke accounts for 1 out of every 18 deaths and is the leading cause of serious long-term disability in the United States. Motion estimation of ultrasound videos (US) of carotid artery (CA) plaques provides important information regarding plaque deformation that should be considered for distinguishing between symptomatic and asymptomatic plaques. In this paper, we present the development of verifiable methods for the estimation of plaque motion. Our methodology is tested on a set of 34 (5 symptomatic and 29 asymptomatic) ultrasound videos of carotid artery plaques. Plaque and wall motion analysis provides information about plaque instability and is used in an attempt to differentiate between symptomatic and asymptomatic cases. The final goal for motion estimation and analysis is to identify pathological conditions that can be detected from motion changes due to changes in tissue stiffness.

  9. Coronary artery atherectomy reduces plaque shear strains: an endovascular elastography imaging study.

    PubMed

    Keshavarz-Motamed, Zahra; Saijo, Yoshifumi; Majdouline, Younes; Riou, Laurent; Ohayon, Jacques; Cloutier, Guy

    2014-07-01

    Mechanical response and properties of the arterial wall can be used to identify the biomechanical instability of plaques and predict their vulnerability to rupture. Shear strain elastography (SSE) is proposed to identify vulnerable plaque features attributed to mechanical structural heterogeneities. The aims of this study were: 1) to report on the potential of SSE to identify atherosclerotic plaques; and 2) to use SSE maps to highlight biomechanical changes in lesion characteristics after directional coronary atherectomy (DCA) interventions. For this purpose, SSE was imaged using in vivo intravascular ultrasound (IVUS) radio-frequency data collected from 12 atherosclerotic patients before and after DCA intervention. Coronary atherosclerotic plaques (pre-DCA) showed high SSE magnitudes with large affected areas. There were good correlations between SSE levels and soft plaque content (i.e., cellular fibrosis, thrombosis and fibrin) (mean |SSE| vs. soft plaque content: r = 0.82, p < 0.01). Significant differences were noticed between SSE images before and after DCA. Stable arteries (post-DCA) exhibited lower values than pre-DCA vessels (e.g., pre-DCA: mean |SSE| = 3.9 ± 0.2% vs. 1.1 ± 0.2% post-DCA, p < 0.001). Furthermore, SSE magnitude was statistically higher in plaques with a high level of inflammation (e.g., mean |SSE| had values of 4.8 ± 0.4% in plaques with high inflammation, whereas it was reduced to 1.8 ± 0.2% with no inflammation, p < 0.01). This study demonstrates the potential of the IVUS-based SSE technique to detect vulnerable plaques in vivo. PMID:24835433

  10. Computer simulation of three-dimensional plaque formation and progression in the carotid artery.

    PubMed

    Filipovic, Nenad; Teng, Zhongzhao; Radovic, Milos; Saveljic, Igor; Fotiadis, Dimitris; Parodi, Oberdan

    2013-06-01

    Atherosclerosis is becoming the number one cause of death worldwide. In this study, three-dimensional computer model of plaque formation and development for human carotid artery is developed. The three-dimensional blood flow is described by the Navier-Stokes equation, together with the continuity equation. Mass transfer within the blood lumen and through the arterial wall is coupled with the blood flow and is modeled by a convection-diffusion equation. The low-density lipoproteins transports in lumen of the vessel and through the vessel tissue are coupled by Kedem-Katchalsky equations. The inflammatory process is modeled using three additional reaction-diffusion partial differential equations. Fluid-structure interaction is used to estimate effective wall stress analysis. Plaque growth functions for volume progression are correlated with shear stress and effective wall stress distribution. We choose two specific patients from MRI study with significant plaque progression. Plaque volume progression using three time points for baseline, 3- and 12-month follow up is fitted. Our results for plaque localization correspond to low shear stress zone and we fitted parameters from our model using nonlinear least-square method. Determination of plaque location and composition, and computer simulation of progression in time for a specific patient shows a potential benefit for the prediction of disease progression. The proof of validity of three-dimensional computer modeling in the evaluation of atherosclerotic plaque burden may shift the clinical information of MRI from morphological assessment toward a functional tool. Understanding and prediction of the evolution of atherosclerotic plaques either into vulnerable or stable plaques are major tasks for the medical community. PMID:23354828

  11. Early Canine Plaque Biofilms: Characterization of Key Bacterial Interactions Involved in Initial Colonization of Enamel

    PubMed Central

    Holcombe, Lucy J.; Patel, Niran; Colyer, Alison; Deusch, Oliver; O’Flynn, Ciaran; Harris, Stephen

    2014-01-01

    Periodontal disease (PD) is a significant problem in dogs affecting between 44% and 63.6% of the population. The main etiological agent for PD is plaque, a microbial biofilm that colonizes teeth and causes inflammation of the gingiva. Understanding how this biofilm initiates on the tooth surface is of central importance in developing interventions against PD. Although the stages of plaque development on human teeth have been well characterized little is known about how canine plaque develops. Recent studies of the canine oral microbiome have revealed distinct differences between the canine and human oral environments and the bacterial communities they support, particularly with respect to healthy plaque. These differences mean knowledge about the nature of plaque formation in humans may not be directly translatable to dogs. The aim of this study was to identify the bacterial species important in the early stages of canine plaque formation in vivo and then use isolates of these species in a laboratory biofilm model to develop an understanding of the sequential processes which take place during the initial colonization of enamel. Supra-gingival plaque samples were collected from 12 dogs at 24 and 48 hour time points following a full mouth descale and polish. Pyrosequencing of the 16S rDNA identified 134 operational taxonomic units after statistical analysis. The species with the highest relative abundance were Bergeyella zoohelcum, Neisseria shayeganii and a Moraxella species. Streptococcal species, which tend to dominate early human plaque biofilms, had very low relative abundance. In vitro testing of biofilm formation identified five primary colonizer species, three of which belonged to the genus Neisseria. Using these pioneer bacteria as a starting point, viable two and three species communities were developed. Combining in vivo and in vitro data has led us to construct novel models of how the early canine plaque biofilm develops. PMID:25463050

  12. Improving quality assurance for assembled COMS eye plaques using a pinhole gamma camera

    SciTech Connect

    Beiki-Ardakani, Akbar; Jezioranski, John; Jaffray, David A.; Yeung, Ivan [Radiation Medicine Program, Princess Margaret Hospital, 610 University Avenue, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, 610 University Avenue, Toronto, Ontario M5G 2M9 (Canada) and Departments of Radiation Oncology and Medical Biophysics, University of Toronto, Toronto, Ontario M5G 2M9 (Canada); Radiation Medicine Program, Princess Margaret Hospital, 610 University Avenue, Toronto, Ontario M5G 2M9, Canada and Department of Radiation Oncology, University of Toronto, Toronto, Ontario M5G 2M9 (Canada)

    2008-10-15

    A quality assurance system has been designed to verify the location and strength of seeds loaded in a brachytherapy eye plaque. This system consists of (1) a pinhole camera in conjunction with a Lumisys ACR-2000i computed radiography (CR) unit to image the location and measure the relative strength of the seeds with autoradiography, and (2) a source strength jig with a survey meter to estimate the total activity of the seeds in the plaque. Five holders of different sizes were made for fixation of the COMS (Collaborative Ocular Melanoma Study) plaques (12, 14, 16, 18, and 20 mm) in the camera. The plaque-to-pinhole distance (d{sub pp}) has been optimized to be 30 mm to give approximately uniform intensity on the CR image for uniformly loaded COMS plaques. The pinhole-to-detector distance (d{sub pd}) can be kept at either 30 mm for 1:1 scale, or at larger distances for higher magnification. For a 1:1 scaling and pinhole diameter of 0.345 mm, useful images are obtained with time-activity product (mCi sec) ranging from 5 to 250 mCi sec. Within this range, the pinhole system is able to differentiate seed activities of >10%. The resulting pinhole autoradiograph is able to (1) confirm the correct number of seeds loaded in the plaque, (2) verify the proper sitting of the seeds in the silastic carrier and the plaque, (3) verify the relative activity distribution of the seeds loaded in the plaque, and (4) potentially evaluate the integrity of the seed. The source strength measurement system is able to measure the total strength of seeds in the plaque ranging from 10 to 80 mCi with an uncertainty of 5%.

  13. Plaque removal efficacy of two electric toothbrushes with different brush head designs.

    PubMed

    Sharma, N C; Qaqish, J G; Galustians, H J; Goyal, C R; Cugini, M A; Thompson, M C; Warren, P R

    2005-06-01

    OBJECTIVES.: To compare the safety and plaque removal efficacy of two electric toothbrushes, one a rechargeable oscillating/pulsating toothbrush with a small round brush head (Oral-B ProfessionalCaretrade mark 7000; PC 7000), the other a battery-operated toothbrush with a dual moving brush head (Crest(R) SpinBrushtrade mark Pro; SBP). METHODS.: The study had a randomised, examiner-blind, two-arm crossover design. All subjects received an oral prophylaxis and used both toothbrushes on alternating days for a two-week practice period. After abstaining from all oral hygiene procedures for 23-25 hours, subjects received an oral tissue examination and those with pre-brushing whole mouth mean plaque scores >/=0.60 measured by the Rustogi et al. Modified Navy Plaque Index were randomly assigned to treatment sequence. Subjects brushed with their assigned toothbrush for 2 minutes using a commercially available dentifrice. Oral tissues were then re-examined and post-brushing plaque scores recorded. After a brief washout period, the above procedures were repeated with the alternate toothbrush. One examiner, blinded to the treatment sequence, performed all clinical measurements. RESULTS.: A total of 70 subjects (24 males and 46 females) were enrolled and completed the study. Each toothbrush was found to be safe and significantly reduced plaque levels after a single brushing. The PC 7000 was significantly more effective in plaque removal than the SBP at all tooth areas, reducing whole mouth plaque by 61% versus 58% and plaque from approximal surfaces by 69% versus 65%, respectively. CONCLUSIONS.: The action of the oscillating/pulsating toothbrush with a small round brush head, Oral-B ProfessionalCare 7000, is more effective in plaque removal than the battery-operated Crest SpinBrush Pro toothbrush with a larger dual moving brush head. PMID:16253751

  14. Numerical analysis of the cooling effect of blood over inflamed atherosclerotic plaque.

    PubMed

    Kim, Taehong; Ley, Obdulia

    2008-06-01

    Atherosclerotic plaques with high likelihood of rupture often show local temperature increase with respect to the surrounding arterial wall temperature. In this work, atherosclerotic plaque temperature was numerically determined during the different levels of blood flow reduction produced by the introduction of catheters at the vessel lumen. The temperature was calculated by solving the energy equation and the Navier-Stokes equations in 2D idealized arterial models. Arterial wall temperature depends on three basic factors: metabolic activity of the inflammatory cells embedded in the plaque, heat convection due to luminal blood flow, and heat conduction through the arterial wall and plaque. The calculations performed serve to simulate transient blood flow reduction produced by the presence of thermography catheters used to measure arterial wall temperature. The calculations estimate the spatial and temporal alterations in the cooling effect of blood flow and plaque temperature during the measurement process. The mathematical model developed provides a tool for analyzing the contribution of factors known to affect heat transfer at the plaque surface. Blood flow reduction leads to a nonuniform temperature increase ranging from 0.1 to 0.25 degrees Celsius in the plaque/lumen interface of the arterial geometries considered in this study. The temperature variation as well as the Nusselt number calculated along the plaque surface strongly depended on the arterial geometry and distribution of inflammatory cells. The calculations indicate that the minimum required time to obtain a steady temperature profile after arterial occlusion is 6 s. It was seen that in arteries with geometries involving bends, the temperature profiles appear asymmetrical and lean toward the downstream edge of the plaque. PMID:18532862

  15. Prevalence and factors associated with scleral hyaline plaque: clinical study of older adults in southeastern Brazil

    PubMed Central

    Horowitz, Soraya; Damasceno, Nadyr; Damasceno, Eduardo

    2015-01-01

    Purpose To investigate the prevalence of scleral hyaline plaque among older adults in the city of Niterói in southeastern Brazil. A second goal was to assess the correlation between scleral hyaline plaque and several age-related diseases, including eye diseases and systemic diseases. Methods The study sample comprised 667 participants who were followed for 15 months. The study had a prospective, longitudinal, observational design that established inclusion and exclusion criteria. The following variables were selected for correlation with scleral hyaline plaque: sex, age, age range, iris color, ethnicity, presence of cataract, moderate to high myopia, age-related macular degeneration (AMD), diabetes mellitus, systemic arterial hypertension, degenerative arthritis, and osteoporosis. These correlations were assessed by means of the ?2 test and Student’s t-test. Multivariate analysis was performed to exclude factors that were potentially associated with aging exclusively but that did not have a direct relationship with hyaline plaque. Binary logistic regression was used to calculate odds ratios, significance, and confidence intervals. Results Scleral hyaline plaques were found in 177 patients (17.54%). There was a statistically significant association between the presence of hyaline plaques and sex (female), age range (?70 years old), ethnicity (Caucasian), cataract, moderate to high myopia, systemic arterial hypertension, degenerative arthritis, and osteoporosis (P<0.05). On multivariate binary logistic regression analysis, only female sex, age range (?70 years), moderate to high myopia, and degenerative arthritis exhibited significant correlation. Conclusion The prevalence of scleral hyaline plaque in the present study was higher than in previous reports in the medical literature. Several age-related diseases exhibited a correlation with scleral hyaline plaque. The most significant factors associated with scleral hyaline plaque were advanced age, female sex, moderate to high myopia, and degenerative arthritis.

  16. Pleural plaques and risk of cancer in Turin, northwestern Italy. An autopsy study

    SciTech Connect

    Mollo, F.; Andrion, A.; Colombo, A.; Segnan, N.; Pira, E.

    1984-10-01

    The relationship between the occurrence of neoplastic diseases and the presence of pleural plaques was studied in a series of 1097 autopsies performed in Turin from the adult general population. In men, pleural plaques showed an association with the presence of laryngeal, pulmonary, esophageal, and colorectal cancer. Only cancer of the larynx was strongly related to the occurrence of such pleural changes. This autopsy investigation confirms previous observations by others based on x-ray findings, and suggests that pleural plaques may be regarded as risk indicators of possibly asbestos-related tumors in the general population.

  17. Carotid Artery Stenting Successfully Prevents Progressive Stroke Due to Mobile Plaque

    PubMed Central

    Oomura, Masahiro; Sato, Chikako; Yamada, Kentaro; Ikeda, Toshimasa; Anan, Chise; Kamimoto, Kaoru

    2015-01-01

    We report a case of progressive ischemic stroke due to a mobile plaque, in which carotid artery stenting successfully prevented further infarctions. A 78-year-old man developed acute multiple infarcts in the right hemisphere, and a duplex ultrasound showed a mobile plaque involving the bifurcation of the left common carotid artery. Maximal medical therapy failed to prevent further infarcts, and the number of infarcts increased with his neurological deterioration. Our present case suggests that the deployment of a closed-cell stent is effective to prevent the progression of the ischemic stroke due to the mobile plaque.

  18. The comparative plaque removal efficacy of two advanced manual toothbrush designs in two independent clinical studies.

    PubMed

    Singh, S M; Battista, G W; Rustogi, K N; DeVizio, W; Volpe, A R; Petrone, M E; Proskin, H M

    2001-01-01

    Two independent studies were conducted to evaluate and compare the clinical performance of two commercially available manual toothbrushes (Colgate Total Professional and the Oral-B Cross Action). Study I was a short-term, examiner-blind crossover clinical trial (N = 30) designed to measure the removal of 24-hour plaque build-up. All subjects refrained from brushing for 24 hours and were screened for dental plaque on the facial and lingual surfaces of all natural teeth using the Rustogi Modified Navy Plaque Index. Patients then received one of the two study toothbrushes and brushed their teeth for a timed one minute. They were then re-assessed for plaque. The data showed that the Colgate Total Professional toothbrush performed better than the Oral-B Cross Action toothbrush in reducing whole-mouth plaque scores (p < 0.001). Study II was a definitive six-week, single-blind clinical trial (N = 55), conducted in harmony with American Dental Association guidelines, to assess the ability of the two toothbrushes to reduce supragingival plaque and gingivitis. In this study, the subjects were stratified into two balanced groups based on their baseline plaque and gingivitis scores. Subjects were then instructed to continue with their normal brushing technique twice daily for one minute with their assigned toothbrush and a commercially available dentifrice. Examinations for plaque (Rustogi Modified Navy Plaque Index), and gingivitis (Loe-Silness Gingival Index) were conducted by the same examiner at baseline, after three weeks, and again after six weeks. The data from this long-term clinical trial showed that the Colgate Total Professional toothbrush exhibited statistically significantly lower plaque and gingivitis scores than did the Oral-B Cross Action toothbrush. The magnitudes of these differences were 29.5% for plaque and 31.1% for gingivitis. These reductions are adequate to support the claim that the Colgate Total Professional toothbrush provides clinically superior control of supragingival plaque and gingivitis, when studied in accordance with the criteria provided by the 1999 Guidelines of the American Dental Association for determining superiority. PMID:11505966

  19. Active and inactive edges of psoriatic plaques: identification by tracing and investigation by laser--Doppler flowmetry and immunocytochemical techniques.

    PubMed

    Hull, S M; Goodfield, M; Wood, E J; Cunliffe, W J

    1989-06-01

    In plaque psoriasis it is likely that biochemical and ultrastructural changes precede the appearance of the typical plaque that is recognizable clinically. Currently, no technique exists by which the very early changes in psoriasis can be investigated. We report a method in which plaques of psoriasis are serially traced to identify their advancing edge. Eight-two untreated plaques from 15 patients and 38 treated plaques from 6 patients were traced over a three-week period; 65% of untreated and 57% of treated plaques showed consistent asymmetrical movement, allowing identification of an active and an inactive edge of each plaque. Using this technique, the active edge of two or more plaques was identified in each of ten patients. Blood flow measured by laser Doppler flowmetry indicated a 2.5-to-4.5-fold increase in cutaneous blood flow at the active edge compared with the inactive edge of each plaque. Punch biopsies from the sites investigated by laser Doppler flowmetry were examined by routine histology and monoclonal antibody immunohistology, but revealed no epidermal change and no T lymphocytic excess when the two areas were compared. We infer from these findings that the earliest change in a developing plaque is an increased blood flow, probably associated with a diffusable, and possibly humoral, initiating factor that accumulates at the active edge, stimulating transformation of normal skin to psoriatic plaque. PMID:2656871

  20. Folate receptor–targeted single-photon emission computed tomography/computed tomography to detect activated macrophages in atherosclerosis: can it distinguish vulnerable from stable atherosclerotic plaques?

    PubMed

    Winkel, Leah C J; Groen, Harald C; van Thiel, Bibi S; Müller, Cristina; van der Steen, Antonius F W; Wentzel, Jolanda J; de Jong, Marion; Van der Heiden, Kim

    2014-01-01

    The need for noninvasive imaging to distinguish stable from vulnerable atherosclerotic plaques is evident. Activated macrophages play a role in atherosclerosis and express folate receptor folate receptor ? (FR-?). The feasibility of folate targeting to detect atherosclerosis was demonstrated in human and mouse plaques, and it was suggested that molecular imaging of FR-? through folate conjugates might be a specific marker for plaque vulnerability. However, these studies did not allow differentiation between stable and vulnerable atherosclerotic plaques. We investigated the feasibility of a folate-based radiopharmaceutical (111)In-EC0800) with high-resolution animal single-photon emission computed tomography/computed tomography (SPECT/CT) to differentiate between stable and vulnerable atherosclerotic plaques in apolipoprotein E(?/?) mice in which we can induce plaques with the characteristics of stable and vulnerable plaques by placing a flow-modifying cast around the common carotid artery. Both plaques showed (111)In-EC0800 uptake, with higher uptake in the vulnerable plaque. However, the vulnerable plaque was larger than the stable plaque. Therefore, we determined tracer uptake per plaque volume and demonstrated higher accumulation of (111)In-EC0800 in the stable plaque normalized to plaque volume. Our data show that (111)In-EC0800 is not a clear-cut marker for the detection of vulnerable plaques but detects both stable and vulnerable atherosclerotic plaques in a mouse model of atherosclerosis. PMID:24757762

  1. Plaque Brachytherapy for Uveal Melanoma: A Vision Prognostication Model

    SciTech Connect

    Khan, Niloufer [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, Ohio (United States); Khan, Mohammad K. [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, Georgia (United States)] [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, Georgia (United States); Bena, James [Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio (United States); Macklis, Roger [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, Ohio (United States)] [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, Cleveland, Ohio (United States); Singh, Arun D., E-mail: singha@ccf.org [Department of Ophthalmic Oncology, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio (United States)

    2012-11-01

    Purpose: To generate a vision prognostication model after plaque brachytherapy for uveal melanoma. Methods and Materials: All patients with primary single ciliary body or choroidal melanoma treated with iodine-125 or ruthenium-106 plaque brachytherapy between January 1, 2005, and June 30, 2010, were included. The primary endpoint was loss of visual acuity. Only patients with initial visual acuity better than or equal to 20/50 were used to evaluate visual acuity worse than 20/50 at the end of the study, and only patients with initial visual acuity better than or equal to 20/200 were used to evaluate visual acuity worse than 20/200 at the end of the study. Factors analyzed were sex, age, cataracts, diabetes, tumor size (basal dimension and apical height), tumor location, and radiation dose to the tumor apex, fovea, and optic disc. Univariate and multivariable Cox proportional hazards were used to determine the influence of baseline patient factors on vision loss. Kaplan-Meier curves (log rank analysis) were used to estimate freedom from vision loss. Results: Of 189 patients, 92% (174) were alive as of February 1, 2011. At presentation, visual acuity was better than or equal to 20/50 and better than or equal to 20/200 in 108 and 173 patients, respectively. Of these patients, 44.4% (48) had post-treatment visual acuity of worse than 20/50 and 25.4% (44) had post-treatment visual acuity worse than 20/200. By multivariable analysis, increased age (hazard ratio [HR] of 1.01 [1.00-1.03], P=.05), increase in tumor height (HR of 1.35 [1.22-1.48], P<.001), and a greater total dose to the fovea (HR of 1.01 [1.00-1.01], P<.001) were predictive of vision loss. This information was used to develop a nomogram predictive of vision loss. Conclusions: By providing a means to predict vision loss at 3 years after treatment, our vision prognostication model can be an important tool for patient selection and treatment counseling.

  2. In vivo Raman spectral pathology of human atherosclerosis and vulnerable plaque

    E-print Network

    Motz, Jason T.

    The rupture of vulnerable atherosclerotic plaque accounts for the majority of clinically significant acute cardiovascular events. Because stability of these culprit lesions is directly related to chemical and morphological ...

  3. Painting blood vessels and atherosclerotic plaques with an adhesive drug depot

    PubMed Central

    Kastrup, Christian J.; Nahrendorf, Matthias; Figueiredo, Jose Luiz; Lee, Haeshin; Kambhampati, Swetha; Lee, Timothy; Cho, Seung-Woo; Gorbatov, Rostic; Iwamoto, Yoshiko; Dang, Tram T.; Dutta, Partha; Yeon, Ju Hun; Cheng, Hao; Pritchard, Christopher D.; Vegas, Arturo J.; Siegel, Cory D.; MacDougall, Samantha; Okonkwo, Michael; Thai, Anh; Stone, James R.; Coury, Arthur J.; Weissleder, Ralph; Langer, Robert; Anderson, Daniel G.

    2012-01-01

    The treatment of diseased vasculature remains challenging, in part because of the difficulty in implanting drug-eluting devices without subjecting vessels to damaging mechanical forces. Implanting materials using adhesive forces could overcome this challenge, but materials have previously not been shown to durably adhere to intact endothelium under blood flow. Marine mussels secrete strong underwater adhesives that have been mimicked in synthetic systems. Here we develop a drug-eluting bioadhesive gel that can be locally and durably glued onto the inside surface of blood vessels. In a mouse model of atherosclerosis, inflamed plaques treated with steroid-eluting adhesive gels had reduced macrophage content and developed protective fibrous caps covering the plaque core. Treatment also lowered plasma cytokine levels and biomarkers of inflammation in the plaque. The drug-eluting devices developed here provide a general strategy for implanting therapeutics in the vasculature using adhesive forces and could potentially be used to stabilize rupture-prone plaques. PMID:23236189

  4. Plaque-forming cells in human cord blood: studies on T and B cell function.

    PubMed Central

    Eibl, M; Zielinski, C C; Ahmad, R; Steurer, F; Rockenschaub, A

    1980-01-01

    Fewer plaque-forming cells (PFC) were found in the cord blood than in adult blood. B cells of newborns seem to be functionally mature. T cells of newborns provide enough help but exert increased suppressor activity. PMID:6449331

  5. Investigations of the 'active' edge of plaque psoriasis: vascular proliferation precedes changes in epidermal keratin.

    PubMed

    Goodfield, M; Hull, S M; Holland, D; Roberts, G; Wood, E; Reid, S; Cunliffe, W

    1994-12-01

    We have investigated markers of epidermal proliferation and differentiation in terms of keratin expression, the morphology of the cutaneous vasculature, and numbers of cutaneous mast cells, in patients with chronic plaque psoriasis. Using the phenomenon of the 'active edge', we have studied these features in the psoriatic plaque itself, and in the clinically normal active and inactive edges of the same plaque. Our results confirm the anticipated changes in keratin profiles, mast cell numbers and psoriatic morphology of the vasculature within the plaque itself. They further indicate that the vascular changes precede the epidermal and mast cell features at the active edge, and that the inactive edge is inactive for all of these variables. Mediators responsible for the vascular proliferation and elongation must be present in increased amounts at the active edge when compared with the inactive, and include locally produced and circulating factors. PMID:7532001

  6. Introduction to the biomechanics of carotid plaque pathogenesis and rupture: review of the clinical evidence

    PubMed Central

    Makris, G C; Nicolaides, A N; Xu, X Y; Geroulakos, G

    2010-01-01

    The management of patients with asymptomatic carotid disease is currently under debate and new methods are warranted for better risk stratification. The role of the biomechanical properties of the atherosclerotic arterial wall together with the effect of different stress types in plaque destabilisation has only been recently investigated. PubMed and Scopus databases were reviewed. There is preliminary clinical evidence demonstrating that the analysis of the combined effect of the various types of biomechanical stress acting on the carotid plaque may help us to identify the vulnerable plaque. At present, MRI and two-dimensional ultrasound are combined with fluid–structure interaction techniques to produce maps of the stress variation within the carotid wall, with increased cost and complexity. Stress wall analysis can be a useful tool for carotid plaque evaluation; however, further research and a multidisciplinary approach are deemed as necessary for further development in this direction. PMID:20647514

  7. A fluorescence lifetime spectroscopy study of matrix metalloproteinases -2 and -9 in human atherosclerotic plaque

    PubMed Central

    Phipps, Jennifer E.; Hatami, Nisa; Galis, Zorina S.; Baker, J. Dennis; Fishbein, Michael C.; Marcu, Laura

    2011-01-01

    Matrix metalloproteinase (MMP) -2 and -9 play important roles in the progression of atherosclerosis. This study aims to determine whether MMP-2 and -9 content in the fibrotic caps of atherosclerotic plaque is correlated with plaque autofluorescence. A time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) system was used to measure the autofluorescence and assess the biochemical composition of human plaques obtained from carotid endarterectomy. Results presented here demonstrate for the first time the ability to characterize the biochemical composition as it relates to MMP-2 and -9 content in the atherosclerotic plaque cap using a label-free imaging technique implemented with a fiberoptic TR-LIFS system. PMID:21770037

  8. Effects of carbon dioxide, Nd-YAG, and argon laser radiation on coronary atheromatous plaques.

    PubMed

    Abela, G S; Normann, S; Cohen, D; Feldman, R L; Geiser, E A; Conti, C R

    1982-12-01

    Laser radiation has been successfully applied in several areas of medical practice. However, its use in cardiology and specifically its effects on obstructive atherosclerosis have largely been unexplored. To evaluate effects of laser radiation on atherosclerotic plaques 25 fresh necropsy atherosclerotic coronary artery segments were exposed to laser radiation with either a carbon dioxide, Nd-YAG, or argon laser. Split or intact segments were prepared under dry conditions or while immersed in saline solution or blood and exposed to laser radiation as power and duration of exposure varied. All 3 lasers were capable of creating controlled injury to atherosclerotic plaques. In general, the magnitude of injury varied according to the total energy delivered (that is, power times duration of exposure. Calcified and noncalcified plaques were penetrated with similar levels of injury. Histologic examination demonstrated that laser radiation produced a wedge incision in the atherosclerotic plaque which was surrounded by zones of thermal and acoustic injury. PMID:6816057

  9. Detection of morphological markers of vulnerable atherosclerotic plaque using multimodal spectroscopy

    E-print Network

    Fitzmaurice, Maryann

    Vulnerable plaques, which are responsible for most acute ischemic events, are presently invisible to x-ray angiography. Their primary morphological features include a thin or ulcerated fibrous cap, a large necrotic core, ...

  10. Distinct Dynamics of Endocytic Clathrin-Coated Pits and Coated Plaques

    Microsoft Academic Search

    Saveez Saffarian; Emanuele Cocucci; Tomas Kirchhausen

    2009-01-01

    Here we classify endocytic structures at the adherent (bottom) surface of many cells in culture into shorter-lived coated pits and longer-lived coated plaques which internalize by different mechanisms.

  11. Challenges on the frontier of intracoronary imaging: atherosclerotic plaque macrophage measurement by optical coherence tomography

    E-print Network

    Bouma, Brett E.

    Cellularity of the fibrous caps of coronary atheromas, manifested by the infiltration of macrophages (average size, 20 to 30 [micrometer]), is thought to weaken the structural integrity of the cap and predispose plaques ...

  12. Plaque quantification by coronary CT and intravascular ultrasound identifies a low CT density core as a marker of plaque instability in acute coronary syndromes.

    PubMed

    Benedek, Theodora; Jako, Beata; Benedek, Imre

    2014-01-01

    The purpose of this study was to demonstrate the relationship between the presence and amount of a low-density core (LDC) with a CT density < 30 Hounsfield units (HU) by coronary computed tomography angiography (CCTA) and IVUS-derived markers of vulnerability in the culprit lesions (CL) of patients with acute coronary syndromes (ACS).In 43 patients with ACS, 105 coronary plaques were scanned using CCTA and IVUS for the quantitative and qualitative assessment of vulnerability markers.The presence of a low attenuation plaque (LAP) was identified in 67.4% of the CL and 29.03% of the non-CL (P = 0.0001). The presence of a LDC > 6.0 mm(3) was significantly correlated with the percentage of the necrotic core (NC) (22.08% versus 7.97%, P = 0.001) and the fibro-fatty tissue by IVUS (18.68% versus 15.87%, P = 0.02). LDC volumes showed a good correlation with the percentage of the NC (r = 0.7303, P < 0.0001) and the fibro-fatty tissue in the CL (r = 0.4928, P < 0.0008). Quantitative plaque analysis revealed a significant difference in plaque composition between CL and non-CL in regards to the LDC (18.45 versus 6.5, P < 0.001), the percentage of NC (20.74 versus 18.74, P = 0.02), fibro-fatty tissue (17.77 versus 15.48, P = 0.002), and fibrotic tissue (51.68 versus 54.8, P = 0.01).VH-IVUS and CCTA plaque quantification showed that the presence of a low-density (< 30 HU) core within the CL of patients with ACS represents a marker of vulnerability and correlates well with other CCTA and IVUS-derived features of vulnerability, particularly the NC of the plaque. PMID:24463925

  13. Drinking habits are associated with changes in the dental plaque microbial community.

    PubMed

    Signoretto, Caterina; Bianchi, Franco; Burlacchini, Gloria; Sivieri, Francesca; Spratt, Dave; Canepari, Pietro

    2010-02-01

    Caries and gingivitis are the most prevalent oral infectious diseases of humans and are due to the accumulation of dental plaque (a microbial biofilm) on the tooth surface and at the gingival margin, respectively. Several in vitro and in vivo studies have shown that many natural components of foods and beverages inhibit the adhesion of and/or exert activity against oral bacteria. These biological activities have mainly been attributed to the polyphenol fraction. In order to explore the possibility that diet can alter the dental plaque community, in this study we evaluated the composition of the microbiota of supra- and subgingival plaque samples collected from 75 adult subjects with different drinking habits (drinkers of coffee, red wine, or water for at least 2 years) by analyzing the microbial population through the separation of PCR-amplified fragments using the denaturing gradient gel electrophoresis (DGGE) technique. The mean numbers of bands of the DGGE profiles from all three categories were evaluated. There were no significant differences between the two kinds of plaque collected from the control group (water drinkers), and this group showed the highest number of bands (supragingival plaque, 18.98 +/- 3.16 bands; subgingival plaque, 18.7 +/- 3.23 bands). The coffee and wine drinker groups generated the lowest numbers of bands for both supragingival plaque (coffee drinkers, 8.25 +/- 3.53 bands; wine drinkers, 7.93 +/- 2.55 bands) and subgingival plaque (coffee drinkers, 8.3 +/- 3.03 bands; wine drinkers, 7.65 +/- 1.68 bands). The differences between coffee drinkers or wine drinkers and the control group (water drinkers) were statistically significant. A total of 34 microorganisms were identified, and the frequency of their distribution in the three subject categories was analyzed. A greater percentage of subjects were positive for facultative aerobes when supragingival plaque was analyzed, while anaerobes were more frequent in subgingival plaque samples. It is noteworthy that the frequency of identification of anaerobes was significantly reduced when the frequencies for coffee and wine drinkers were compared with the frequencies for subjects in the control group. The DGGE profiles of the organisms in both plaque samples from all groups were generated and were used to construct dendrograms. A number of distinct clusters of organisms from water, coffee, and wine drinkers were formed. The clustering of some of the DGGE results into cohort-specific clusters implies similarities in the microbiotas within these groups and relevant differences in the microbiotas between cohorts. This supports the notion that the drinking habits of the subjects may influence the microbiota at both the supragingival and the subgingival levels. PMID:19955272

  14. Drinking Habits Are Associated with Changes in the Dental Plaque Microbial Community?

    PubMed Central

    Signoretto, Caterina; Bianchi, Franco; Burlacchini, Gloria; Sivieri, Francesca; Spratt, Dave; Canepari, Pietro

    2010-01-01

    Caries and gingivitis are the most prevalent oral infectious diseases of humans and are due to the accumulation of dental plaque (a microbial biofilm) on the tooth surface and at the gingival margin, respectively. Several in vitro and in vivo studies have shown that many natural components of foods and beverages inhibit the adhesion of and/or exert activity against oral bacteria. These biological activities have mainly been attributed to the polyphenol fraction. In order to explore the possibility that diet can alter the dental plaque community, in this study we evaluated the composition of the microbiota of supra- and subgingival plaque samples collected from 75 adult subjects with different drinking habits (drinkers of coffee, red wine, or water for at least 2 years) by analyzing the microbial population through the separation of PCR-amplified fragments using the denaturing gradient gel electrophoresis (DGGE) technique. The mean numbers of bands of the DGGE profiles from all three categories were evaluated. There were no significant differences between the two kinds of plaque collected from the control group (water drinkers), and this group showed the highest number of bands (supragingival plaque, 18.98 ± 3.16 bands; subgingival plaque, 18.7 ± 3.23 bands). The coffee and wine drinker groups generated the lowest numbers of bands for both supragingival plaque (coffee drinkers, 8.25 ± 3.53 bands; wine drinkers, 7.93 ± 2.55 bands) and subgingival plaque (coffee drinkers, 8.3 ± 3.03 bands; wine drinkers, 7.65 ± 1.68 bands). The differences between coffee drinkers or wine drinkers and the control group (water drinkers) were statistically significant. A total of 34 microorganisms were identified, and the frequency of their distribution in the three subject categories was analyzed. A greater percentage of subjects were positive for facultative aerobes when supragingival plaque was analyzed, while anaerobes were more frequent in subgingival plaque samples. It is noteworthy that the frequency of identification of anaerobes was significantly reduced when the frequencies for coffee and wine drinkers were compared with the frequencies for subjects in the control group. The DGGE profiles of the organisms in both plaque samples from all groups were generated and were used to construct dendrograms. A number of distinct clusters of organisms from water, coffee, and wine drinkers were formed. The clustering of some of the DGGE results into cohort-specific clusters implies similarities in the microbiotas within these groups and relevant differences in the microbiotas between cohorts. This supports the notion that the drinking habits of the subjects may influence the microbiota at both the supragingival and the subgingival levels. PMID:19955272

  15. Differences in microbiological composition of saliva and dental plaque in subjects with different drinking habits.

    PubMed

    Signoretto, Caterina; Burlacchini, Gloria; Bianchi, Franco; Cavalleri, Giacomo; Canepari, Pietro

    2006-10-01

    Several foods have been shown to contain natural components (especially polyphenols) which display anti-adhesive properties against Streptococcus mutans, the aetiological agent responsible for dental crown caries, as well as inhibition of glucosyltransferases, which are the S. mutans enzymes involved in the synthesis of an adherent, water-insoluble glucan from sucrose. Other studies have demonstrated an in vitro action on oral plaque biofilm formation and desorption. This study evaluated whether the activity displayed in vitro by food compounds could affect the microbiological composition of saliva and dental plaque of subjects with a diet rich in these foods, comparing the results with those obtained from subjects with a different diet. The foods considered were: coffee, barley coffee, tea and wine. A total of 93 subjects were recruited into the study. Six samples of both plaque and saliva were collected from each subject at roughly one-monthly intervals. Total bacteria, total streptococci, S. mutans and lactobacilli counts were determined by culture in both saliva and dental plaque. The highest bacterial titres were recorded for the control population, while each drinking habit subgroup showed counts roughly one log lower than the controls. These differences in bacterial counts proved statistically significant (P<0.05). As far as dental plaque was concerned, while total counts did not significantly vary per mg of plaque in the subjects belonging to the different drinking habit subgroups, a significant decrease (P<0.05) was observed in those subjects drinking coffee, tea, barley coffee and wine when mutans streptococci and lactobacilli were evaluated. In several cases a more than one log decrease was observed. Plaque indices were also determined, and a significant (P<0.05) reduction in values was recorded in the subjects belonging the specific drinking habit subgroups compared to the control group. This study indicates that there is a correlation between consumption of specific foods and oral health in terms of reduced plaque deposition and lower counts of odontopathogens. PMID:17201096

  16. SOPROCARE - 450 nm wavelength detection tool for microbial plaque and gingival inflammation: a clinical study

    NASA Astrophysics Data System (ADS)

    Rechmann, P.; Liou, Shasan W.; Rechmann, Beate M.; Featherstone, John D.

    2014-02-01

    Gingivitis due to microbial plaque and calculus can lead over time if left untreated to advanced periodontal disease with non-physiological pocket formation. Removal of microbial plaque in the gingivitis stage typically achieves gingival health. The SOPROCARE camera system emits blue light at 450 nm wavelength using three blue diodes. The 450 nm wavelength is located in the non-ionizing, visible spectral wavelength region and thus is not dangerous. It is assumed that using the SOPROCARE camera in perio-mode inflamed gingiva can easily be observed and inflammation can be scored due to fluorescence from porphyrins in blood. The assumption is also that illumination of microbial plaque with blue light induces fluorescence due to the bacteria and porphyrin content of the plaque and thus can help to make microbial plaque and calculus visible. Aim of the study with 55 subjects was to evaluate the ability of the SOPROCARE fluorescence camera system to detect, visualize and allow scoring of microbial plaque in comparison to the Turesky modification of the Quigley and Hein plaque index. A second goal was to detect and score gingival inflammation and correlated the findings to the Silness and Löe gingival inflammation index. The study showed that scoring of microbial plaque as well as gingival inflammation levels similar to the established Turesky modified Quigley Hein index and the Silness and Löe gingival inflammation index can easily be done using the SOPROCARE fluorescence system in periomode. Linear regression fits between the different clinical indices and SOPROCARE scores in fluorescence perio-mode revealed the system's capacity for effective discrimination between scores.

  17. Elevated White Blood Cell Count and Carotid Plaque Thickness The Northern Manhattan Stroke Study

    Microsoft Academic Search

    Mitchell S. Elkind; Jianfeng Cheng; Bernadette Boden-Albala; Myunghee C. Paik; Ralph L. Sacco

    Background and Purpose—Elevated leukocyte count has been associated with cardiovascular and cerebrovascular disease in several epidemiological studies. We sought to determine whether white blood cell count (WBC) is associated with carotid plaque thickness in a stroke-free, multiethnic cohort. Methods—For this cross-sectional analysis, WBC was measured in stroke-free community subjects undergoing carotid duplex Doppler ultrasound. Maximal internal carotid plaque thickness (MICPT)

  18. Phage Display Identification of CD100 in Human Atherosclerotic Plaque Macrophages and Foam Cells

    PubMed Central

    Luque, Maria Carolina Aquino; Gutierrez, Paulo Sampaio; Debbas, Victor; Martins, Waleska Kerllen; Puech-Leao, Pedro; Porto, Georgia; Coelho, Verônica; Boumsell, Laurence; Kalil, Jorge; Stolf, Beatriz

    2013-01-01

    Atherosclerosis is a complex disease in which vessels develop plaques comprising dysfunctional endothelium, monocyte derived lipid laden foam cells and activated lymphocytes. Considering that humans and animal models of the disease develop quite distinct plaques, we used human plaques to search for proteins that could be used as markers of human atheromas. Phage display peptide libraries were probed to fresh human carotid plaques, and a bound phage homologous to plexin B1, a high affinity receptor for CD100, was identified. CD100 is a member of the semaphorin family expressed by most hematopoietic cells and particularly by activated T cells. CD100 expression was analyzed in human plaques and normal samples. CD100 mRNA and protein were analyzed in cultured monocytes, macrophages and foam cells. The effects of CD100 in oxLDL-induced foam cell formation and in CD36 mRNA abundance were evaluated. Human atherosclerotic plaques showed strong labeling of CD100/SEMA4D. CD100 expression was further demonstrated in peripheral blood monocytes and in in vitro differentiated macrophages and foam cells, with diminished CD100 transcript along the differentiation of these cells. Incubation of macrophages with CD100 led to a reduction in oxLDL-induced foam cell formation probably through a decrease of CD36 expression, suggesting for the first time an atheroprotective role for CD100 in the human disease. Given its differential expression in the numerous foam cells and macrophages of the plaques and its capacity to decrease oxLDL engulfment by macrophages we propose that CD100 may have a role in atherosclerotic plaque development, and may possibly be employed in targeted treatments of these atheromas. PMID:24098722

  19. Multi-slice computed tomography with N1177 identifies ruptured atherosclerotic plaques in rabbits

    Microsoft Academic Search

    Jozef Leo Van Herck; Guido R. Y. De Meyer; Wim Martinet; Rodrigo A. Salgado; Bharati Shivalkar; Roel De Mondt; Helene Van De Ven; Annick Ludwig; Pieter Van Der Veken; Luc Van Vaeck; Hidde Bult; Arnold G. Herman; Christiaan J. Vrints

    2010-01-01

    Rupture-prone and ruptured plaques are characterized by the presence of large numbers of macrophages. N1177 is a contrast\\u000a agent consisting of iodinated nanoparticles that are selectively phagocytosed by macrophages. The aim of this study was to\\u000a investigate the effect of N1177 on the CT attenuation of rupture-prone and ruptured plaques in rabbits. In addition, we examined\\u000a in vitro whether uptake

  20. Proton-induced X-ray emission analysis of atherosclerotic plaques of the carotid bifurcation

    Microsoft Academic Search

    M. Peltomaa; K. Mattila; J. Wolf; M. Hyvönen-Dabek

    1992-01-01

    The trace elements of both calcified atherosclerotic plaques and plaque-free vessel walls of the carotid bifurcation from\\u000a 31 autopsies were investigated using the proton-induced X-ray emission (PIXE) method. The trace elements studied were phosphorus\\u000a (P), calcium (Ca), chrome (Cr), iron (Fe), copper (Cu), zinc (Zn), lead (Pb), selenium (Se), bromine (Br), strontium (Sr),\\u000a and rubidium (Rb). All samples contained Fe

  1. Soil factors influencing ferric hydroxide plaque formation on roots of Typha latifolia L

    Microsoft Academic Search

    S. M. Macfie; A. A. Crowder

    1987-01-01

    The amount of ferric hydroxide plaque deposited onTypha latifolia roots varied between wetlands submerged throughout the growing season. Plaque formation was positively correlated with extractable\\u000a iron in the substrate and pH, and negatively correlated with the percent organic matter and percent inorganic carbonates in\\u000a the soil. All the above correlations were significant but weak, and in a stepwise regression analysis

  2. Common Carotid Intima-Media Thickness Predicts Occurrence of Carotid Atherosclerotic Plaques

    Microsoft Academic Search

    Mahmoud Zureik; Pierre Ducimetie re; Pierre-Jean Touboul; Dominique Courbon; Claire Bonithon-Kopp; Claudine Berr; Christine Magne

    Abstract—The role of the increase in the common,carotid artery (CCA) intima-media wall thickness (IMT) in the atherosclerotic process is questionable. This longitudinal study examined,the predictive value of CCA-IMT measured at baseline examination (at sites free of plaques) on the occurrence of atherosclerotic plaques in the extracranial carotid arteries during 4 years of follow-up study in a sample of 1010 subjects

  3. PCR detection of Streptococcus mutans and Aggregatibacter actinomycetemcomitans in dental plaque samples from Haitian adolescents

    Microsoft Academic Search

    Walter J. Psoter; Yao Ge; Stefanie L. Russell; Zhou Chen; Ralph V. Katz; Germain Jean-Charles; Yihong Li

    2011-01-01

    Streptococcus mutans and Aggregatibacter actinomycetemcomitans are oral pathogens associated with dental caries and periodontitis, respectively. The aim of this study was to determine\\u000a the colonization of these two microorganisms in the dental plaque of a group of Haitian adolescents using two different polymerase\\u000a chain reaction (PCR) methods, standard PCR, and quantitative real-time PCR (qPCR) assays. Fifty-four pooled supra-gingival\\u000a plaque samples

  4. Early-onset Formation of Parenchymal Plaque Amyloid Abrogates Cerebral Microvascular Amyloid Accumulation in Transgenic Mice*

    PubMed Central

    Xu, Feng; Kotarba, AnnMarie E.; Ou-Yang, Ming-Hsuan; Fu, Ziao; Davis, Judianne; Smith, Steven O.; Van Nostrand, William E.

    2014-01-01

    The fibrillar assembly and deposition of amyloid ? (A?) protein, a key pathology of Alzheimer disease, can occur in the form of parenchymal amyloid plaques and cerebral amyloid angiopathy (CAA). Familial forms of CAA exist in the absence of appreciable parenchymal amyloid pathology. The molecular interplay between parenchymal amyloid plaques and CAA is unclear. Here we investigated how early-onset parenchymal amyloid plaques impact the development of microvascular amyloid in transgenic mice. Tg-5xFAD mice, which produce non-mutated human A? and develop early-onset parenchymal amyloid plaques, were bred to Tg-SwDI mice, which produce familial CAA mutant human A? and develop cerebral microvascular amyloid. The bigenic mice presented with an elevated accumulation of A? and fibrillar amyloid in the brain compared with either single transgenic line. Tg-SwDI/Tg-5xFAD mice were devoid of microvascular amyloid, the prominent pathology of Tg-SwDI mice, but exhibited larger parenchymal amyloid plaques compared with Tg-5xFAD mice. The larger parenchymal amyloid deposits were associated with a higher loss of cortical neurons and elevated activated microglia in the bigenic Tg-SwDI/Tg-5xFAD mice. The periphery of parenchymal amyloid plaques was largely composed of CAA mutant A?. Non-mutated A? fibril seeds promoted CAA mutant A? fibril formation in vitro. Further, intrahippocampal administration of biotin-labeled CAA mutant A? peptide accumulated on and adjacent to pre-existing parenchymal amyloid plaques in Tg-5xFAD mice. These findings indicate that early-onset parenchymal amyloid plaques can serve as a scaffold to capture CAA mutant A? peptides and prevent their accumulation in cerebral microvessels. PMID:24828504

  5. Multiple Atherosclerotic Plaque Rupture in Acute Coronary Syndrome: A Three-Vessel Intravascular Ultrasound Study

    Microsoft Academic Search

    G. Rioufol; G. Finet; I. Ginon; X. André-Fouët; R. Rossi; E. Vialle; E. Desjoyaux; G. Convert; J. F. Huret; A. Tabib

    2002-01-01

    Background—To test the hypothesis of general atherosclerotic plaque destabilization during acute coronary syndrome (ACS), the present study sought to analyze the 3 coronary arteries by systematic intravascular ultrasound scan (IVUS). Methods and Results—Seventy-two arteries were explored in 24 patients referred for percutaneous coronary intervention after a first ACS with troponin I elevation. Fifty plaque ruptures (mean, 2.08 per patient; range,

  6. Functionalization of gadolinium metallofullerenes for detecting atherosclerotic plaque lesions by cardiovascular magnetic resonance

    PubMed Central

    2013-01-01

    Background The hallmark of atherosclerosis is the accumulation of plaque in vessel walls. This process is initiated when monocytic cells differentiate into macrophage foam cells under conditions with high levels of atherogenic lipoproteins. Vulnerable plaque can dislodge, enter the blood stream, and result in acute myocardial infarction and stroke. Imaging techniques such as cardiovascular magnetic resonance (CMR) provides one strategy to identify patients with plaque accumulation. Methods We synthesized an atherosclerotic-targeting contrast agent (ATCA) in which gadolinium (Gd)-containing endohedrals were functionalized and formulated into liposomes with CD36 ligands intercalated into the lipid bilayer. In vitro assays were used to assess the specificity of the ATCA for foam cells. The ability of ATCA to detect atherosclerotic plaque lesions in vivo was assessed using CMR. Results The ATCA was able to detect scavenger receptor (CD36)-expressing foam cells in vitro and were specifically internalized via the CD36 receptor as determined by focused ion beam/scanning electron microscopy (FIB-SEM) and Western blotting analysis of CD36 receptor-specific signaling pathways. The ATCA exhibited time-dependent accumulation in atherosclerotic plaque lesions of ApoE ?/? mice as determined using CMR. No ATCA accumulation was observed in vessels of wild type (C57/b6) controls. Non-targeted control compounds, without the plaque-targeting moieties, were not taken up by foam cells in vitro and did not bind plaque in vivo. Importantly, the ATCA injection was well tolerated, did not demonstrate toxicity in vitro or in vivo, and no accumulation was observed in the major organs. Conclusions The ATCA is specifically internalized by CD36 receptors on atherosclerotic plaque providing enhanced visualization of lesions under physiological conditions. These ATCA may provide new tools for physicians to non-invasively detect atherosclerotic disease. PMID:23324435

  7. 64Cu-DOTATATE PET/MRI for Detection of Activated Macrophages in Carotid Atherosclerotic Plaques

    PubMed Central

    Sandholt, Benjamin Vikjær; Keller, Sune Høgild; Hansen, Adam Espe; Clemmensen, Andreas Ettrup; Sillesen, Henrik; Højgaard, Liselotte; Ripa, Rasmus Sejersten; Kjær, Andreas

    2015-01-01

    Objective— A feature of vulnerable atherosclerotic plaques of the carotid artery is high activity and abundance of lesion macrophages. There is consensus that this is of importance for plaque vulnerability, which may lead to clinical events, such as stroke and transient ischemic attack. We used positron emission tomography (PET) and the novel PET ligand [64Cu] [1,4,7,10-tetraazacyclododecane-N,N?,N?,N?-tetraacetic acid]-d-Phe1,Tyr3-octreotate (64Cu-DOTATATE) to specifically target macrophages via the somatostatin receptor subtype-2 in vivo. Approach and Results— Ten patients underwent simultaneous PET/MRI to measure 64Cu-DOTATATE uptake in carotid artery plaques before carotid endarterectomy. 64Cu-DOTATATE uptake was significantly higher in symptomatic plaque versus the contralateral carotid artery (P<0.001). Subsequently, a total of 62 plaque segments were assessed for gene expression of selected markers of plaque vulnerability using real-time quantitative polymerase chain reaction. These results were compared with in vivo 64Cu-DOTATATE uptake calculated as the mean standardized uptake value. Univariate analysis of real-time quantitative polymerase chain reaction and PET showed that cluster of differentiation 163 (CD163) and CD68 gene expression correlated significantly but weakly with mean standardized uptake value in scans performed 85 minutes post injection (P<0.001 and P=0.015, respectively). Subsequent multivariate analysis showed that CD163 correlated independently with 64Cu-DOTATATE uptake (P=0.031) whereas CD68 did not contribute significantly to the final model. Conclusions— The novel PET tracer 64Cu-DOTATATE accumulates in atherosclerotic plaques of the carotid artery. CD163 gene expression correlated independently with 64Cu-DOTATATE uptake measured by real-time quantitative polymerase chain reaction in the final multivariate model, indicating that 64Cu-DOTATATE PET is detecting alternatively activated macrophages. This association could potentially improve noninvasive identification and characterization of vulnerable plaques. PMID:25977567

  8. Ultrasonography reveals nail thickening in patients with chronic plaque psoriasis.

    PubMed

    Gisondi, P; Idolazzi, L; Girolomoni, G

    2012-11-01

    Nail psoriasis is usually investigated and diagnosed by clinical examination. Ultrasonography is a non-invasive imaging technique for studying soft tissue involvement. The objective of this study was to estimate nail involvement in patients with chronic plaque psoriasis by ultrasonography. Prevalence, clinical type and severity of nail involvement according to nail psoriasis and severity index (NAPSI) were investigated in 138 patients with psoriasis. The thickness of the plate and bed of the fingernails was measured in 54 patients with psoriasis, 46 healthy controls and 37 patients with chronic eczema, using an ultrasonographic system equipped with a frequency transducer of 18 MHz. The prevalence of nail psoriasis was 73 % (102 out of 138). Onycholysis and thickening of the nail plate were the most common clinical type affecting 56 and 50 % of patients, respectively; splinter haemorrhages was the less common involving 10 % of patients. The mean NAPSI score was 18.4 ± 17.5 (SD; range 0-107). The thickness of fingernail plate and bed was significantly higher in patients with psoriasis with nail disease compared to healthy controls and patients with chronic eczema (p < 0.001). There was a linear correlation between NAPSI and plate and bed nail thickness (r = 0.52 and r = 0.38, p = 0.001). Increased nail plate and bed thickness was observed also in patients with psoriasis without clinically apparent nail involvement. In conclusion, thickening of the nail is a common feature of nail psoriasis also in patients without clinically apparent nail involvement. PMID:23011659

  9. Prevalence and severity of plaque-induced gingivitis in a Saudi adult population

    PubMed Central

    Idrees, Majdy M.; Azzeghaiby, Saleh N.; Hammad, Mohammad M.; Kujan, Omar B.

    2014-01-01

    Objectives: To evaluate the prevalence and severity of plaque-induced gingivitis among a Saudi adult population in Riyadh region. Methods: Three hundred and eighty-five eligible participants in this cross-sectional study were recruited from routine dental patients attending the oral diagnosis clinic at Al-Farabi College in Riyadh, Saudi Arabia from June 2013 to December 2013. A clinical examination was performed by 2 dentists to measure the gingival and plaque indices of Löe and Silness for each participant. Results: The prevalence of gingivitis was 100% among adult subjects aged between 18-40 years old. Moreover, the mean gingival index was 1.68±0.31, which indicates a moderate gingival inflammation. In fact, males showed more severe signs of gingival inflammation compared with females (p=0.001). In addition, the mean plaque index was 0.875±0.49, which indicates a good plaque status of the participants. Interestingly, the age was not related either to the gingival inflammation (p=0.13), or to the amount of plaque accumulation (p=0.17). However, males were more affected than females (p=0.005). Conclusion: The results of this study show that plaque accumulation is strongly associated with high prevalence of moderate to severe gingivitis among Saudi subjects. PMID:25399215

  10. Type I collagen gene expression in human atherosclerosis. Localization to specific plaque regions.

    PubMed Central

    Rekhter, M. D.; Zhang, K.; Narayanan, A. S.; Phan, S.; Schork, M. A.; Gordon, D.

    1993-01-01

    Because collagen is a major component of the human atherosclerotic plaque, factors controlling collagen synthesis may have a profound influence on the volume growth of these intimal lesions. In human arteries, we compared normal vs atherosclerotic media vs intimas for type I collagen gene expression using immunocytochemistry and in situ messenger RNA hybridization with subsequent correlations with plaque topographical features. We also determined the associations of such collagen gene expression with proximity to monocyte/macrophages and T lymphocytes. Type I collagen synthesis appears to be upregulated in atherosclerotic plaques compared with their underlying medias and normal internal mammary arteries and coronary diffuse intimal thickenings. At least in established and advanced coronary and carotid plaques, type I collagen gene expression is focal and especially prevalent in fibrous cap and vascularized regions. Although macrophages and type I procollagen messenger RNA and protein are both found in atherosclerotic plaques, no apparent spatial correlation between macrophage presence and type I procollagen presence was found within these atherosclerotic intimas. Type I procollagen presence appears to be negatively associated with the spatial presence of T cells. Thus, human atherosclerotic plaques exhibit nonuniform patterns of type I collagen gene expression. Although the biochemical determinants of this focal gene expression have yet to be determined, it is conceivable that stimulatory/inhibitory cytokines and other factors (eg hemodynamics) play important roles in determining the focal nature of collagen synthesis in atherosclerosis. Images Figure 1 Figure 3 PMID:7504887

  11. Cnm67p Is a Spacer Protein of the Saccharomyces cerevisiae Spindle Pole Body Outer Plaque

    PubMed Central

    Schaerer, Florian; Morgan, Garry; Winey, Mark; Philippsen, Peter

    2001-01-01

    In Saccharomyces cerevisiae, the spindle pole body (SPB) is the functional homolog of the mammalian centrosome, responsible for the organization of the tubulin cytoskeleton. Cytoplasmic (astral) microtubules essential for the proper segregation of the nucleus into the daughter cell are attached at the outer plaque on the SPB cytoplasmic face. Previously, it has been shown that Cnm67p is an integral component of this structure; cells deleted for CNM67 are lacking the SPB outer plaque and thus experience severe nuclear migration defects. With the use of partial deletion mutants of CNM67, we show that the N- and C-terminal domains of the protein are important for nuclear migration. The C terminus, not the N terminus, is essential for Cnm67p localization to the SPB. On the other hand, only the N terminus is subject to protein phosphorylation of a yet unknown function. Electron microscopy of SPB serial thin sections reveals that deletion of the N- or C-terminal domains disturbs outer plaque formation, whereas mutations in the central coiled-coil domain of Cnm67p change the distance between the SPB core and the outer plaque. We conclude that Cnm67p is the protein that connects the outer plaque to the central plaque embedded in the nuclear envelope, adjusting the space between them by the length of its coiled-coil. PMID:11514632

  12. Error propagation in the characterization of atheromatic plaque types based on imaging.

    PubMed

    Athanasiou, Lambros S; Rigas, George; Sakellarios, Antonis; Bourantas, Christos V; Stefanou, Kostas; Fotiou, Evangelos; Exarchos, Themis P; Siogkas, Panagiotis; Naka, Katerina K; Parodi, Oberdan; Vozzi, Federico; Teng, Zhongzhao; Young, Victoria E L; Gillard, Jonathan H; Prati, Francesco; Michalis, Lampros K; Fotiadis, Dimitrios I

    2015-10-01

    Imaging systems transmit and acquire signals and are subject to errors including: error sources, signal variations or possible calibration errors. These errors are included in all imaging systems for atherosclerosis and are propagated to methodologies implemented for the segmentation and characterization of atherosclerotic plaque. In this paper, we present a study for the propagation of imaging errors and image segmentation errors in plaque characterization methods applied to 2D vascular images. More specifically, the maximum error that can be propagated to the plaque characterization results is estimated, assuming worst-case scenarios. The proposed error propagation methodology is validated using methods applied to real datasets, obtained from intravascular imaging (IVUS) and optical coherence tomography (OCT) for coronary arteries, and magnetic resonance imaging (MRI) for carotid arteries. The plaque characterization methods have recently been presented in the literature and are able to detect the vessel borders, and characterize the atherosclerotic plaque types. Although, these methods have been extensively validated using as gold standard expert annotations, by applying the proposed error propagation methodology a more realistic validation is performed taking into account the effect of the border detection algorithms error and the image formation error into the final results. The Pearson's coefficient of the detected plaques has changed significantly when the method was applied to IVUS and OCT, while there was not any variation when the method was applied to MRI data. PMID:26165637

  13. Vulnerable plaque detection and quantification with gold particle-enhanced computed tomography in atherosclerotic mouse models.

    PubMed

    De Wilde, David; Trachet, Bram; Van der Donckt, Carole; Vandeghinste, Bert; Descamps, Benedicte; Vanhove, Christian; De Meyer, Guido R Y; Segers, Patrick

    2015-06-01

    AbstractRecently, an apolipoprotein E-deficient (ApoE-/-) mouse model with a mutation (C1039G+/-) in the fibrillin-1 (Fbn1) gene (ApoE-/-Fbn1C1039G+/- mouse model) was developed showing vulnerable atherosclerotic plaques, prone to rupture, in contrast to the ApoE-/- mouse model, where mainly stable plaques are present. One indicator of plaque vulnerability is the level of macrophage infiltration. Therefore, this study aimed to measure and quantify in vivo the macrophage infiltration related to plaque development and progression. For this purpose, 5-weekly consecutive gold nanoparticle-enhanced micro-computed tomography (microCT) scans were acquired. Histology confirmed that the presence of contrast agent coincided with the presence of macrophages. Based on the microCT scans, regions of the artery wall with contrast agent present were calculated and visualized in three dimensions. From this information, the contrast-enhanced area and contrast-enhanced centerline length were calculated for the branches of the carotid bifurcation (common, external, and internal carotid arteries). Statistical analysis showed a more rapid development and a larger extent of plaques in the ApoE-/-Fbn1C1039G+/- compared to the ApoE-/- mice. Regional differences between the branches were also observable and quantifiable. We developed and applied a methodology based on gold particle-enhanced microCT to visualize the presence of macrophages in atherosclerotic plaques in vivo. PMID:26044776

  14. Chronic imaging of amyloid plaques in the live mouse brain using multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Bacskai, Brian J.; Kajdasz, Stephen T.; Christie, R. H.; Zipfel, Warren R.; Williams, Rebecca M.; Kasischke, Karl A.; Webb, Watt W.; Hyman, B. T.

    2001-04-01

    Transgenic mice expressing the human Amyloid Precursor Protein (APP) develop amyloid plaques as they age. These plaques resemble those found in the human disease. Multiphoton laser scanning microscopy combined with a novel surgical approach was used to measure amyloid plaque dynamics chronically in the cortex of living transgenic mice. Thioflavine S (thioS) was used as a fluorescent marker of amyloid deposits. Multiphoton excitation allowed visualization of amyloid plaques up to 200 micrometers deep into the brain. The surgical site could be imaged repeatedly without overt damage to the tissue, and individual plaques within this volume could be reliably identified over periods of several days to several months. On average, plaque sizes remained constant over time, supporting a model of rapid deposition, followed by relative stability. Alternative reporters for in vivo histology include thiazine red, and FITC-labeled amyloid-(Beta) peptide. We also present examples of multi-color imaging using Hoechst dyes and FITC-labeled tomato lectin. These approaches allow us to observe cell nuclei or microglia simultaneously with amyloid-(Beta) deposits in vivo. Chronic imaging of a variety of reporters in these transgenic mice should provide insight into the dynamics of amyloid-(Beta) activity in the brain.

  15. Relationship of MMP-14 and TIMP-3 Expression with Macrophage Activation and Human Atherosclerotic Plaque Vulnerability

    PubMed Central

    Johnson, Jason L.; Jenkins, Nicholas P.; Huang, Wei-Chun; Sala-Newby, Graciela B.; Scholtes, Vincent P. W.; Moll, Frans L.; Pasterkamp, Gerard; Newby, Andrew C.

    2014-01-01

    Matrix metalloproteinase-14 (MMP-14) promotes vulnerable plaque morphology in mice, whereas tissue inhibitor of metalloproteinases-3 (TIMP-3) overexpression is protective. MMP-14hi??TIMP-3lo rabbit foam cells are more invasive and more prone to apoptosis than MMP-14lo??TIMP-3hi cells. We investigated the implications of these findings for human atherosclerosis. In vitro generated macrophages and foam-cell macrophages, together with atherosclerotic plaques characterised as unstable or stable, were examined for expression of MMP-14, TIMP-3, and inflammatory markers. Proinflammatory stimuli increased MMP-14 and decreased TIMP-3 mRNA and protein expression in human macrophages. However, conversion to foam-cells with oxidized LDL increased MMP-14 and decreased TIMP-3 protein, independently of inflammatory mediators and partly through posttranscriptional mechanisms. Within atherosclerotic plaques, MMP-14 was prominent in foam-cells with either pro- or anti-inflammatory macrophage markers, whereas TIMP-3 was present in less foamy macrophages and colocalised with CD206. MMP-14 positive macrophages were more abundant whereas TIMP-3 positive macrophages were less abundant in plaques histologically designated as rupture prone. We conclude that foam-cells characterised by high MMP-14 and low TIMP-3 expression are prevalent in rupture-prone atherosclerotic plaques, independent of pro- or anti-inflammatory activation. Therefore reducing MMP-14 activity and increasing that of TIMP-3 could be valid therapeutic approaches to reduce plaque rupture and myocardial infarction. PMID:25301980

  16. Carotid plaque characterization using CT and MRI scans for synergistic image analysis

    NASA Astrophysics Data System (ADS)

    Getzin, Matthew; Xu, Yiqin; Rao, Arhant; Madi, Saaussan; Bahadur, Ali; Lennartz, Michelle R.; Wang, Ge

    2014-09-01

    Noninvasive determination of plaque vulnerability has been a holy grail of medical imaging. Despite advances in tomographic technologies , there is currently no effective way to identify vulnerable atherosclerotic plaques with high sensitivity and specificity. Computed tomography (CT) and magnetic resonance imaging (MRI) are widely used, but neither provides sufficient information of plaque properties. Thus, we are motivated to combine CT and MRI imaging to determine if the composite information can better reflect the histological determination of plaque vulnerability. Two human endarterectomy specimens (1 symptomatic carotid and 1 stable femoral) were imaged using Scanco Medical Viva CT40 and Bruker Pharmascan 16cm 7T Horizontal MRI / MRS systems. ?CT scans were done at 55 kVp and tube current of 70 mA. Samples underwent RARE-VTR and MSME pulse sequences to measure T1, T2 values, and proton density. The specimens were processed for histology and scored for vulnerability using the American Heart Association criteria. Single modality-based analyses were performed through segmentation of key imaging biomarkers (i.e. calcification and lumen), image registration, measurement of fibrous capsule, and multi-component T1 and T2 decay modeling. Feature differences were analyzed between the unstable and stable controls, symptomatic carotid and femoral plaque, respectively. By building on the techniques used in this study, synergistic CT+MRI analysis may provide a promising solution for plaque characterization in vivo.

  17. Imaging Plaques to Predict and Better Manage Patients with Acute Coronary Events

    PubMed Central

    Garcia-Garcia, Hector M.; Jang, Ik-Kyung; Serruys, Patrick W.; Kovacic, Jason C.; Narula, Jagat; Fayad, Zahi A.

    2014-01-01

    Culprit lesions of patients who have had an acute coronary syndrome commonly are ruptured coronary plaques with superimposed thrombus. The precursor of such lesions is an inflamed thin-capped fibroatheroma. These plaques can be imaged by means of invasive techniques such as intravascular ultrasound (and derived techniques), optical coherence tomography and near-infrared spectroscopy. Very often these patients exhibit similar (multiple) plaques beyond the culprit lesion. These remote plaques can be assessed non invasively by computed tomography angiography and magnetic resonance imaging and also using invasive imaging. The detection of these remote plaques is not only feasible, but also in natural history studies have been associated with clinical coronary events. Different systemic pharmacological treatments have been studied (mostly statins) with modest success and therefore newer approaches are being tested. Local treatment for such lesions is in its infancy and larger, prospective and randomized trials are needed. This review will describe the pathological and imaging findings in culprit lesions of patients with acute coronary syndrome and as well as the assessment of remote plaques. In addition, the pharmacological and local treatment options will be reviewed. PMID:24902974

  18. Carotid plaque assessment using fast 3D isotropic resolution black-blood MRI.

    PubMed

    Balu, Niranjan; Yarnykh, Vasily L; Chu, Baocheng; Wang, Jinnan; Hatsukami, Thomas; Yuan, Chun

    2011-03-01

    Black-blood MRI is a promising tool for carotid atherosclerotic plaque burden assessment and compositional analysis. However, current sequences are limited by large slice thickness. Accuracy of measurement can be improved by moving to isotropic imaging but can be challenging for patient compliance due to long scan times. We present a fast isotropic high spatial resolution (0.7×0.7×0.7 mm3) three-dimensional black-blood sequence (3D-MERGE) covering the entire cervical carotid arteries within 2 min thus ensuring patient compliance and diagnostic image quality. The sequence is optimized for vessel wall imaging of the carotid bifurcation based on its signal properties. The optimized sequence is validated on patients with significant carotid plaque. Quantitative plaque morphology measurements and signal-to-noise ratio measures show that 3D-MERGE provides good blood suppression and comparable plaque burden measurements to existing MRI protocols. 3D-MERGE is a promising new tool for fast and accurate plaque burden assessment in patients with atherosclerotic plaque. PMID:20941742

  19. Targeting blood thrombogenicity precipitates atherothrombotic events in a mouse model of plaque destabilization

    PubMed Central

    Liu, Xiaoling; Ni, Mei; Ma, Lianyue; Yang, Jianmin; Wang, Lin; Liu, Fangfang; Dong, Mei; Yang, Xiaoyan; Zhang, Mei; Lu, Huixia; Wang, Jingjing; Zhang, Cheng; Jiang, Fan; Zhang, Yun

    2015-01-01

    Although some features of plaque instability can be observed in genetically modified mouse models, atherothrombosis induction in mice has been attested to be difficult. We sought to test the hypothesis that alterations in blood thrombogenicity might have an essential role in the development of atherothrombosis in ApoE?/? mice. In a mouse model of plaque destabilization established in our laboratory, we targeted blood thrombogenicity by systemically overexpressing murine prothrombin via adenovirus-mediated gene transfer. Systemic overexpression of prothrombin increased blood thrombogenicity, and remarkably, precipitated atherothrombotic events in 70% of the animals. The affected plaques displayed features of culprit lesions as seen in human coronary arteries, including fibrous cap disruption, luminal thrombosis, and plaque hemorrhage. Treatment with aspirin and clopidogrel substantially reduced the incidence of atherothrombosis in this model. Mechanistically, increased inflammation, apoptosis and upregulation of metalloproteinases contributed to the development of plaque destabilization and atherothrombosis. As conclusions, targeting blood thrombogenicity in mice can faithfully reproduce the process of atherothrombosis as occurring in human coronary vessels. Our results suggest that blood-plaque interactions are critical in the development of atherothrombosis in mice, substantiating the argument that changes in blood coagulation status may have a determinant role in the onset of acute coronary syndrome. PMID:25959659

  20. The comparative evaluation of the effects of tongue cleaning on existing plaque levels in children.

    PubMed

    Winnier, J Jasmin; Rupesh, S; Nayak, Ullal Anand; Reddy, Venugopal; Prasad Rao, Arun

    2013-09-01

    The present study compared and evaluated the effects of tongue scraping and tongue brushing on existing plaque levels in children. The investigation was a single blind, stratified comparison of three parallel groups of children who performed either tongue scraping or tongue brushing along with tooth brushing or only tooth brushing twice daily under professional supervision for a 21 day period. Dental plaque was recorded using the plaque index described by Silness and Loe at baseline, on day 10 and on day 21. All data was subjected to statistical analysis using Wilcoxon's Signed Ranks Sum Test and Mann-Whitney U-test. The results of the present study show that the tongue scraping and tongue brushing groups showed statistically significant reductions in plaque levels after 10 days and also after 21 days. It was also noted that both tongue scraping and tongue brushing were equally effective in reducing the plaque load in children. How to cite this article: Winnier JJ, Rupesh S, Nayak UA, Reddy V, Rao AP. The Comparative Evaluation of the Effects of Tongue Cleaning on Existing Plaque Levels in Children. Int J Clin Pediatr Dent 2013;6(3):188-192. PMID:25206220

  1. Contribution of neovascularization and intraplaque haemorrhage to atherosclerotic plaque progression and instability.

    PubMed

    Chistiakov, D A; Orekhov, A N; Bobryshev, Y V

    2015-03-01

    Atherosclerosis is a continuous pathological process that starts early in life and progresses frequently to unstable plaques. Plaque rupture leads to deleterious consequences such as acute coronary syndrome, stroke and atherothrombosis. The vulnerable lesion has several structural and functional hallmarks that distinguish it from the stable plaque. The unstable plaque has large necrotic core (over 40% plaque volume) composed of cholesterol crystals, cholesterol esters, oxidized lipids, fibrin, erythrocytes and their remnants (haeme, iron, haemoglobin), and dying macrophages. The fibrous cap is thin, depleted of smooth muscle cells and collagen, and is infiltrated with proinflammatory cells. In unstable lesion, formation of neomicrovessels is increased. These neovessels have weak integrity and leak thereby leading to recurrent haemorrhages. Haemorrhages deliver erythrocytes to the necrotic core where they degrade promoting inflammation and oxidative stress. Inflammatory cells mostly presented by monocytes/macrophages, neutrophils and mast cells extravagate from bleeding neovessels and infiltrate adventitia where they support chronic inflammation. Plaque destabilization is an evolutionary process that could start at early atherosclerotic stages and whose progression is influenced by many factors including neovascularization, intraplaque haemorrhages, formation of cholesterol crystals, inflammation, oxidative stress and intraplaque protease activity. PMID:25515699

  2. Effects of Exogenous Gibberellic Acid3 on Iron and Manganese Plaque Amounts and Iron and Manganese Uptake in Rice

    PubMed Central

    Guo, Yue; Zhu, Changhua; Gan, Lijun; Ng, Denny; Xia, Kai

    2015-01-01

    Gibberellins (GA) regulate various components of plant development. Iron and Mn plaque result from oxiding and hydroxiding Fe and Mn, respectively, on the roots of aquatic plant species such as rice (Oryza sativa L.). In this study, we found that exogenous gibberellic acid3 (GA3) spray decreased Fe plaque, but increased Mn plaque, with applications of Kimura B nutrient solution. Similar effects from GA3, leading to reduced Fe plaque and increased Mn plaque, were also found by scanning electron microscopy and energy dispersive X-ray spectrometric microanalysis. Reduced Fe plaque was observed after applying GA3 to the groups containing added Fe2+ (17 and 42 mg•L-1) and an increasing trend was detected in Mn plaques of the Mn2+ (34 and 84 mg•L-1) added treatments. In contrast, an inhibitor of GA3, uniconazole, reversed the effects of GA3. The uptake of Fe or Mn in rice plants was enhanced after GA3 application and Fe or Mn plaque production. Strong synergetic effects of GA3 application on Fe plaque production were detected. However, no synergetic effects on Mn plaque production were detected. PMID:25710173

  3. Method for verifying the air kerma strength of I-125 plaques for the treatment of ocular melanoma.

    PubMed

    Zimmermann, L W; Wilkinson, D Allan

    2014-01-01

    The purpose of this work was to develop a method for easily verifying that the activity or air kerma strength of pre-assembled eye plaques, used in the treatment of ocular melanomas, agrees with the activity or air kerma strength called for in the treatment plan. A Capintec CRC-7 Dose Calibrator with its standard vial/syringe sample holder was used to measure the activity of pre-assembled COMS and Eye Physics EP917 eye plaques using IsoAid Advantage I-125 seeds. Plaque activity measurements were made by placing the plaque face up in the center of a 5 cm tall Styrofoam insert in the source holder. Activity measurements were made with the source holder rotated to four angles (0°, 90°, 180°, and 270°). The average of these four values was converted to air kerma strength and divided by the assay air kerma strength, from the NIST traceable source calibration, and decayed to the plaque measurement date, to determine a plaque calibration factor. The average of the calibration factors for each plaque type was used to establish a calibration factor for each plaque type. Several partially loaded plaque configurations were included in this study and different methods were used to determine the effects of partial loading. This verification method is easy to implement with commonly available equipment and is effective in identifying possible errors. During this two-year study, the air kerma strength of 115 eye plaques was checked and 11 possible errors were identified. PMID:25207419

  4. Increased expression of fatty acid binding protein 4 and leptin in resident macrophages characterises atherosclerotic plaque rupture

    PubMed Central

    Lee, K.; Santibanez-Koref, M.; Polvikoski, T.; Birchall, D.; Mendelow, A.D.; Keavney, B.

    2013-01-01

    Objective Resident macrophages play an important role in atheromatous plaque rupture. The macrophage gene expression signature associated with plaque rupture is incompletely defined due to the complex cellular heterogeneity in the plaque. We aimed to characterise differential gene expression in resident plaque macrophages from ruptured and stable human atheromatous lesions. Methods and results We performed genome-wide expression analyses of isolated macrophage-rich regions of stable and ruptured human atherosclerotic plaques. Plaques present in carotid endarterectomy specimens were designated as stable or ruptured using clinical, radiological and histopathological criteria. Macrophage-rich regions were excised from 5 ruptured and 6 stable plaques by laser micro-dissection. Transcriptional profiling was performed using Affymetrix microarrays. The profiles were characteristic of activated macrophages. At a false discovery rate of 10%, 914 genes were differentially expressed between stable and ruptured plaques. The findings were confirmed in fourteen further stable and ruptured samples for a subset of eleven genes with the highest expression differences (p < 0.05). Pathway analysis revealed that components of the PPAR/Adipocytokine signaling pathway were the most significantly upregulated in ruptured compared to stable plaques (p = 5.4 × 10?7). Two key components of the pathway, fatty-acid binding-protein 4 (FABP4) and leptin, showed nine-fold (p = 0.0086) and five-fold (p = 0.0012) greater expression respectively in macrophages from ruptured plaques. Conclusions We found differences in gene expression signatures between macrophages isolated from stable and ruptured human atheromatous plaques. Our findings indicate the involvement of FABP4 and leptin in the progression of atherosclerosis and plaque rupture, and suggest that down-regulation of PPAR/adipocytokine signaling within plaques may have therapeutic potential. PMID:23122912

  5. MR Imaging of Carotid Plaque Composition During Lipid-Lowering Therapy

    PubMed Central

    Zhao, Xue-Qiao; Dong, Li; Hatsukami, Tom; Phan, Binh An; Chu, Baocheng; Moore, Andrew; Lane, Trevor; Neradilek, Moni B.; Polissar, Nayak; Monick, Duane; Lee, Colin; Underhill, Hunter; Yuan, Chun

    2013-01-01

    OBJECTIVES The purpose of this study was to test the lipid depletion hypothesis and to establish the time course of change in carotid plaque morphology and composition during lipid therapy using high-resolution magnetic resonance imaging (MRI). BACKGROUND Lipid therapy is thought to improve plaque stability and reduce cardiovascular events by targeting the plaque rupture risk features such as large lipid core, thin fibrous cap, and high level of inflammatory infiltrates. However, the plaque stabilizing process during lipid therapy has not been clearly demonstrated in humans and in vivo. METHODS Subjects with coronary or carotid artery disease, apolipoprotein B ?120 mg/dl, and lipid treatment history <1 year, were randomly assigned to atorvastatin monotherapy or to atorvastatin-based combination therapies with appropriate placebos for 3 years. All subjects underwent high-resolution, multicontrast bilateral carotid MRI scans at baseline and annually for 3 years. All images were analyzed for quantification of wall area and plaque composition blinded to therapy, laboratory results, and clinical course. RESULTS After 3 years of lipid therapy, the 33 subjects with measurable lipid-rich necrotic core (LRNC) at baseline had a significant reduction in plaque lipid content: LRNC volume decreased from 60.4 ± 59.5 mm3 to 37.4 ± 69.5 mm3 (p < 0.001) and %LRNC (LRNC area/wall area in the lipid-rich regions) from 14.2 ± 7.0% to 7.4 ± 8.2% (p < 0.001). The time course showed that %LRNC decreased by 3.2 (p < 0.001) in the first year, by 3.0 (p = 0.005) in the second year, and by 0.91 (p = 0.2) in the third year. Changes in LRNC volume followed the same pattern. Percent wall volume (100 × wall/outer wall, a ratio of volumes) in the lipid-rich regions significantly decreased from 52.3 ± 8.5% to 48.6 ± 9.7% (p = 0.002). Slices containing LRNC had significantly more percent wall volume reduction than those without (?4.7% vs. ?1.4%, p = 0.02). CONCLUSIONS Intensive lipid therapy significantly depletes carotid plaque lipid. Statistically significant plaque lipid depletion is observed after 1 year of treatment and continues in the second year, and precedes plaque regression. (Using Magnetic Resonance Imaging to Evaluate Carotid Artery Plaque Composition in People Receiving Cholesterol-Lowering Medications [The CPC Study]; NCT00715273). PMID:21920335

  6. {sup 106}Ruthenium Plaque Therapy (RPT) for Retinoblastoma

    SciTech Connect

    Murakami, Naoya, E-mail: namuraka@ncc.go.jp [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)] [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Suzuki, Shigenobu [Department of Ophthalmic Oncology, National Cancer Center Hospital, Tokyo (Japan)] [Department of Ophthalmic Oncology, National Cancer Center Hospital, Tokyo (Japan); Ito, Yoshinori [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)] [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Yoshimura, Ryoichi [Department of Diagnostic Radiology and Oncology, Head and Neck Reconstruction Division, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan)] [Department of Diagnostic Radiology and Oncology, Head and Neck Reconstruction Division, Graduate School, Tokyo Medical and Dental University, Tokyo (Japan); Inaba, Koji; Kuroda, Yuki; Morota, Madoka; Mayahara, Hiroshi; Sakudo, Mototake; Wakita, Akihisa; Okamoto, Hiroyuki; Sumi, Minako; Kagami, Yoshikazu [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)] [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Nakagawa, Keiichi; Ohtomo, Kuni [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan)] [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Itami, Jun [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)] [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)

    2012-09-01

    Purpose: To evaluate the effectiveness of episcleral {sup 106}ruthenium plaque therapy (RPT) in the management of retinoblastoma. Methods and Materials: One hundred one RPTs were retrospectively analyzed that were performed in 90 eyes of 85 patients with retinoblastoma at National Cancer Center Hospital between 1998 and 2008. Each RPT had a corresponding tumor and 101 tumors were considered in the analysis of local control. Median follow-up length was 72.8 months. Median patient age at the RPT was 28 months. Median prescribed doses at reference depth and outer surface of the sclera were 47.4 Gy and 162.3 Gy, respectively. Results: Local control rate (LCR) and ocular retention rate (ORR) at 2 years were 33.7% and 58.7%, respectively. Unilateral disease, International Classification of Retinoblastoma group C or more advanced at the first presentation or at the time of RPT, vitreous and/or subretinal seeding, tumor size greater than 5 disc diameter (DD), reference depth greater than 5 mm, dose rate at reference depth lower than 0.7 Gy/hour, dose at the reference depth lower than 35 Gy, and (biologically effective dose with an {alpha}/{beta} ratio of 10 Gy) at the reference depth lower than 40 Gy{sub 10} were associated with unfavorable LCR. Two patients died of metastatic disease. Radiation complications included retinal detachment in 12 eyes (13.3%), proliferative retinopathy in 6 (6.7%), rubeosis iris in 2 (2.2%), and posterior subcapsular cataract in 23 (25.6%). Conclusion: RPT is an effective eye-preserving treatment for retinoblastoma.

  7. Effect of Fluoride and Chlorhexidine Digluconate Mouthrinses on Plaque Biofilms

    PubMed Central

    Rabe, Per; Twetman, Svante; Kinnby, Bertil; Svensäter, Gunnel; Davies, Julia R

    2015-01-01

    Objective : To develop a model in which to investigate the architecture of plaque biofilms formed on enamel surfaces in vivo and to compare the effects of anti-microbial agents of relevance for caries on biofilm vitality. Materials and Methodology : Enamel discs mounted on healing abutments in the pre-molar region were worn by three subjects for 7 days. Control discs were removed before subjects rinsed with 0.1% chlorhexidine digluconate (CHX) or 0.2% sodium fluoride (NaF) for 1 minute. Biofilms were stained with Baclight Live/Dead and z-stacks of images created using confocal scanning laser micoscopy. The levels of vital and dead/damaged bacteria in the biofilms, assessed as the proportion of green and red pixels respectively, were analysed using ImageTrak® software. Results : The subjects showed individual differences in biofilm architecture. The thickness of the biofilms varied from 28-96µm although cell density was always the greatest in the middle layers. In control biofilms, the overall levels of vitality were high (71-98%) especially in the area closest to the enamel interface. Rinsing with either CHX or NaF caused a similar reduction in overall vitality. CHX exerted an effect throughout the biofilm, particularly on the surface of cell clusters whereas NaF caused cell damage/death mainly in the middle to lower biofilm layers. Conclusion : We describe a model that allows the formation of mature, undisturbed oral biofilms on human enamel surfaces in vivo and show that CHX and NaF have a similar effect on overall vitality but differ in their sites of action. PMID:25870718

  8. Impact of flow rates in a cardiac cycle on correlations between advanced human carotid plaque progression and mechanical flow shear stress and plaque wall stress

    PubMed Central

    2011-01-01

    Background Mechanical stresses are known to play important roles in atherosclerotic plaque initiation, progression and rupture. It has been well-accepted that atherosclerosis initiation and early progression correlate negatively with flow wall shear stresses (FSS). However, mechanisms governing advanced plaque progression are not well understood. Method In vivo serial MRI data (patient follow-up) were acquired from 14 patients after informed consent. Each patient had 2-4 scans (scan interval: 18 months). Thirty-two scan pairs (baseline and follow-up scans) were formed with slices matched for model construction and analysis. Each scan pair had 4-10 matched slices which gave 400-1000 data points for analysis (100 points per slice on lumen). Point-wise plaque progression was defined as the wall thickness increase (WTI) at each data point. 3D computational models with fluid-structure interactions were constructed based on in vivo serial MRI data to extract flow shear stress and plaque wall stress (PWS) on all data points to quantify correlations between plaque progression and mechanical stresses (FSS and PWS). FSS and PWS data corresponding to both maximum and minimum flow rates in a cardiac cycle were used to investigate the impact of flow rates on those correlations. Results Using follow-up scans and maximum flow rates, 19 out of 32 scan pairs showed a significant positive correlation between WTI and FSS (positive/negative/no significance correlation ratio = 19/9/4), and 26 out of 32 scan pairs showed a significant negative correlation between WTI and PWS (correlation ratio = 2/26/4). Corresponding to minimum flow rates, the correlation ratio for WTI vs. FSS and WTI vs. PWS were (20/7/5) and (2/26/4), respectively. Using baseline scans, the correlation ratios for WTI vs. FSS were (10/12/10) and (9/13/10) for maximum and minimum flow rates, respectively. The correlation ratios for WTI vs. PWS were the same (18/5/9), corresponding to maximum and minimum flow rates. Conclusion Flow shear stress corresponding to the minimum flow rates in a cardiac cycle had slightly better correlation with WTI, compared to FSS corresponding to maximum flow rates. Choice of maximum or minimum flow rates had no impact on PWS correlations. Advanced plaque progression correlated positively with flow shear stress and negatively with plaque wall stress using follow-up scans. Correlation results using FSS at the baseline scan were inconclusive. PMID:21771293

  9. Xylitol: a review of its action on mutans streptococci and dental plaque--its clinical significance.

    PubMed

    Trahan, L

    1995-02-01

    Many mechanisms have been proposed to explain the caries preventive effect of xylitol as a total or partial dietary sugar substitute. This article reviews the current knowledge of the effect of xylitol on the microbial population of dental plaque, particularly on mutans streptococci, in the light of an ecological concept of the oral environment and of the potential clinical significance. A noncariogenic commensal plaque flora constitutes the biotic component of a balanced ecosystem compatible with dental health. Dietary sugars, particularly sucrose, and sugar substitutes are abiotic environmental factors that can shift the delicate balance of the ecosystem towards a more or less cariogenic microbiota. Most dietary sugars are fermented by plaque microorganisms, favour the establishment of a cariogenic microflora and contribute to bacterial virulence. The vast majority of plaque bacteria, however, are incapable of fermenting xylitol into cariogenic acid end-products. There is no evidence that the plaque microbiota can adapt to metabolise xylitol or can be enriched with xylitol-metabolising cells even after long exposure to xylitol. Accumulated intracellularly as a non-metabolisable metabolite by mutans streptococci, xylitol inhibits its growth in vitro and reduces the amount of plaque and the number of mutans streptococci in both the plaque and saliva of xylitol consumers. When present in the oral environment xylitol not only prevents a shift of the bacterial community towards a more cariogenic microflora but also selects for a mutants population that was shown to have weakened virulence factors in preliminary in vitro experiments and in rats. Further research is needed to fully understand the clinical importance in the prevention of caries of this xylitol-selected population. PMID:7607748

  10. Doxycycline Stabilizes Vulnerable Plaque via Inhibiting Matrix Metalloproteinases and Attenuating Inflammation in Rabbits

    PubMed Central

    Dong, Mei; Zhong, Lin; Chen, Wen Qiang; Ji, Xiao Ping; Zhang, Mei; Zhao, Yu Xia; Li, Li; Yao, Gui Hua; Zhang, Peng Fei; Zhang, Cheng; Zhang, Lei; Zhang, Yun

    2012-01-01

    Enhanced matrix metalloproteinases (MMPs) activity is implicated in the process of atherosclerotic plaque instability. We hypothesized that doxycycline, a broad MMPs inhibitor, was as effective as simvastatin in reducing the incidence of plaque disruption. Thirty rabbits underwent aortic balloon injury and were fed a high-fat diet for 20 weeks. At the end of week 8, the rabbits were divided into three groups for 12-week treatment: a doxycycline-treated group that received oral doxycycline at a dose of 10 mg/kg/d, a simvastatin-treated group that received oral simvastatin at a dose of 5 mg/kg/d, and a control group that received no treatment. At the end of week 20, pharmacological triggering was performed to induce plaque rupture. Biochemical, ultrasonographic, pathologic, immunohistochemical and mRNA expression studies were performed. The results showed that oral administration of doxycycline resulted in a significant increase in the thickness of the fibrous cap of the aortic plaque whereas there was a substantial reduction of MMPs expression, local and systemic inflammation, and aortic plaque vulnerability. The incidence of plaque rupture with either treatment (0% for both) was significantly lower than that for controls (56.0%, P<0.05). There was no significant difference between doxycycline-treated group and simvastatin-treated group in any serological, ultrasonographic, pathologic, immunohistochemical and mRNA expression measurement except for the serum lipid levels that were higher with doxycycline than with simvastatin treatment. In conclusion, doxycycline at a common antimicrobial dose stabilizes atherosclerotic lesions via inhibiting matrix metalloproteinases and attenuating inflammation in a rabbit model of vulnerable plaque. These effects were similar to a large dose of simvastatin and independent of serum lipid levels. PMID:22737253

  11. Role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism.

    PubMed

    Zhong, Z X; Li, B; Li, C R; Zhang, Q F; Liu, Z D; Zhang, P F; Gu, X F; Luo, H; Li, M J; Luo, H S; Ye, G H; Wen, F L

    2015-02-01

    Our aim was to investigate the role of chemokines in promoting instability of coronary atherosclerotic plaques and the underlying molecular mechanism. Coronary angiography and intravascular ultrasound (IVUS) were performed in 60 stable angina pectoris (SAP) patients and 60 unstable angina pectoris (UAP) patients. The chemotactic activity of monocytes in the 2 groups of patients was examined in Transwell chambers. High-sensitivity C-reactive protein (hs-CRP), monocyte chemoattractant protein-1 (MCP-1), regulated on activation in normal T-cell expressed and secreted (RANTES), and fractalkine in serum were examined with ELISA kits, and expression of MCP-1, RANTES, and fractalkine mRNA was examined with real-time PCR. In the SAP group, 92 plaques were detected with IVUS. In the UAP group, 96 plaques were detected with IVUS. The plaques in the UAP group were mainly lipid 51.04% (49/96) and the plaques in the SAP group were mainly fibrous 52.17% (48/92). Compared with the SAP group, the plaque burden and vascular remodeling index in the UAP group were significantly greater than in the SAP group (P<0.01). Chemotactic activity and the number of mobile monocytes in the UAP group were significantly greater than in the SAP group (P<0.01). Concentrations of hs-CRP, MCP-1, RANTES, and fractalkine in the serum of the UAP group were significantly higher than in the serum of the SAP group (P<0.05 or P<0.01), and expression of MCP-1, RANTES, and fractalkine mRNA was significantly higher than in the SAP group (P<0.05). MCP-1, RANTES, and fractalkine probably promote instability of coronary atherosclerotic plaque. PMID:25424368

  12. The effectiveness of a magnetized water oral irrigator (Hydro Floss) on plaque, calculus and gingival health.

    PubMed

    Johnson, K E; Sanders, J J; Gellin, R G; Palesch, Y Y

    1998-04-01

    The purpose of this study was to evaluate the effects of a magnetized water oral irrigator on plaque, calculus and gingival health. 29 patients completed this double-blind crossover study. Each patient was brought to baseline via an oral prophylaxis with a plaque index < or = 1 and a gingival index < or = 1. Subjects used the irrigator for a period of 3 months with the magnet and 3 months without the magnet. After each 3 month interval, data were collected using the plaque index, gingival index, and accretions index. The repeated measures analysis on plaque, gingival and calculus indices yielded a statistically-significant period effect for PlI (p=0.0343), GI (p=0.0091), and approached significance for calculus (p=0.0593). This meant that the effect of irrigation resulted in a decrease of all indices over time. Therefore, the treatment effect on each index was evaluated using only the measurements obtained at the end of the first period (i.e., assuming a parallel design). Irrigation with magnetized water resulted in 64% less calculus compared to the control group. The reduction was statistically significant (p< or =0.02). The reduction by 27% in gingival index was not statistically significant. The reduction in plaque was minimal (2.2%). A strong positive correlation between the plaque index and the Watt accretion index was observed. The magnetized water oral irrigator could be a useful adjunct in the prevention of calculus accumulation in periodontal patients, but appears to have minimal effect on plaque reduction. The results indicated a clinical improvement in the gingival index, but this was not a statistically significant finding. PMID:9565283

  13. Neuropeptide Y Receptors in Carotid Plaques of Symptomatic and Asymptomatic Patients: Effect of Inflammatory Cytokines

    PubMed Central

    Pankajakshan, Divya; Jia, Guanghong; Pipinos, Iraklis; Tyndall, Steve H.; Agrawal, Devendra K

    2011-01-01

    Aims Cytokines released by the immune cells at the site of plaque milieu induce smooth muscle cell apoptosis to promote plaque instability. But, neuropeptide Y (NPY), a pleotropic factor, may modulate the effects of cytokines in atherosclerotic plaques of patients with carotid stenosis. Our aim was to investigate the relative expression of NPY-Y1, NPY-Y2 and NPY-Y5 receptors on carotid plaque vascular smooth muscle cells (pVSMCs) of symptomatic (S) and asymptomatic (AS) patients and examine the effect of inflammatory cytokines on the expression of NPY receptors, that may attenuate plaque rupture. Methods and Results In healthy carotid artery, there was significantly increased immunopositivity and increased mRNA transcripts of NPY-Y1 and NPY-Y5 receptors in thin sections and isolated VSMCs, respectively, compared to S and AS plaques. However, the NPY-Y2 expression was higher in S and AS pVSMCs than controls. Stimulation of the cells with TNF-?, IL-12 or IFN-? (50 ng/ml) decreased mRNA transcripts of NPY-Y1 and NPY-Y5 and increased NPY-Y2 mRNAs in VSMCs of healthy carotid artery. The effect of the cytokines on mRNA transcripts of NPY-Y5 and NPY-Y2 in pVSMCs of S and AS patients was similar to healthy VSMCs, but with variable effect on NPY-Y1. Conclusion Increased expression of NPY-Y2 receptors in symptomatic pVSMCs than in healthy and asymptomatic subjects suggests a potential role of NPY-Y2 in plaque instability. This is further supported by the pronounced effect of atheroma-associated cytokines to increase NPY-Y2 mRNA transcripts in pVSMCs of patients with carotid stenosis. PMID:21352822

  14. Statins use and coronary artery plaque composition: Results from the International Multicenter CONFIRM Registry

    PubMed Central

    Nakazato, Ryo; Gransar, Heidi; Berman, Daniel S.; Cheng, Victor Y.; Lin, Fay Y.; Achenbach, Stephan; Al-Mallah, Mouaz; Budoff, Matthew J.; Cademartiri, Filippo; Callister, Tracy Q.; Chang, Hyuk-Jae; Cury, Ricardo C.; Chinnaiyan, Kavitha; Chow, Benjamin J.W.; Delago, Augustin; Hadamitzky, Martin; Hausleiter, Joerg; Kaufmann, Philipp; Maffei, Erica; Raff, Gilbert; Shaw, Leslee J.; Villines, Todd C.; Dunning, Allison; Feuchtner, Gudrun; Kim, Yong-Jin; Leipsic, Jonathon; Min, James K.

    2014-01-01

    Objective The effect of statins on coronary artery plaque features beyond stenosis severity is not known. Coronary CT angiography (CCTA) is a novel non-invasive method that permits direct visualization of coronary atherosclerotic features, including plaque composition. We evaluated the association of statin use to coronary plaque composition type in patients without known coronary artery disease (CAD) undergoing CCTA. Methods From consecutive individuals, we identified 6673 individuals (2413 on statin therapy and 4260 not on statin therapy) with no known CAD and available statin use status. We studied the relationship between statin use and the presence and extent of specific plaque composition types, which was graded as non-calcified (NCP), mixed (MP), or calcified (CP) plaque. Results The mean age was 59 ± 11 (55% male). Compared to the individuals not taking statins, those taking statins had higher prevalence of risk factors and obstructive CAD. In multivariable analyses, statin use was associated with increased the presence of MP [odds ratio (OR) 1.46, 95% confidence interval (CI) 1.27–1.68), p < 0.001] and CP (OR 1.54, 95% CI 1.36–1.74, p < 0.001), but not NCP (OR 1.11, 95% CI 0.96–1.29, p = 0.1). Further, in multivariable analyses, statin use was associated with increasing numbers of coronary segments possessing MP (OR 1.52, 95% CI 1.34–1.73, p < 0.001) and CP (OR 1.52, 95% CI 1.36–1.70, p < 0.001), but not coronary segments with NCP (OR 1.09, 95% CI 0.94–1.25, p = 0.2). Conclusion Statin use is associated with an increased prevalence and extent of coronary plaques possessing calcium. The longitudinal effect of statins on coronary plaque composition warrants further investigation. PMID:22981406

  15. Fluoride in plaque fluid and saliva after NaF or MFP rinses.

    PubMed

    Ekstrand, J

    1997-10-01

    A micro-analytic method, capable of measuring the fluoride concentration in 5 nl of plaque fluid, was used to follow changes in fluoride concentration in saliva and plaque fluid at 6 single tooth-sites in 6 subjects for 180 min after a 0.048 M fluoride rinse as a NaF or MFP (sodium monofluorophosphate) solution. The maximum fluoride concentrations in saliva after NaF was 13x higher than with MFP. About 5% of the total amount of fluoride following the 20 ml NaF rinse was retained in the oral cavity. The corresponding figure followig MFP was <1%. The saliva/plaque fluid fluoride ratios for upper molars and lower incisors were significantly higher than for the upper incisors and lower molars. There was a tendency for a decline in the ratios with respect to time for all sites. To characterize the plaque fluid fluoride intra-oral single-site distribution and clearance, fluoride concentration versus time (AUC) was calculated from 10 to 60 min after a rinse. The NaF AUC followed the order: upper incisor, lower molar, upper molar and lower incisors reflecting a different exposure and clearance pattern due to the different access of the plaque to saliva. The MFP AUC values varied more, but were all significantly lower than the NaF AUC values. Analysis of plaque fluid fluoride curves at various sites revealed an exponential decline in most cases. With NaF, the baseline plaque fluid fluoride levels were not reached within 3 h. It is concluded that NaF solutions result in a significantly higher intra-oral fluoride exposure than MFP solutions. The fluoride distribution and clearance of fluoride from different sites in the oral cavity are linked to salivary access to these sites. These site-specific differences may have clinical consequences with regard to the dynamics of fluoride in the de- and remineralization processes. PMID:9395113

  16. Comparison of the clinical efficacy of a new manual toothbrush on gingivitis reduction and plaque removal.

    PubMed

    Mankodi, Suru; Wachs, Gerald N; Petrone, Dolores M; Chaknis, Patricia; Petrone, Margaret; DeVizio, William; Volpe, Anthony R

    2004-10-01

    The objective of this controlled, examiner blind, 4-week clinical study was to evaluate and compare the safety and efficacy of a newly designed manual toothbrush, the Colgate 360 degrees toothbrush, to the Oral-B Indicator toothbrush for the control of supragingival plaque and gingivitis. A total of 82 subjects from the northern New Jersey area reported to the clinical facility for a baseline plaque and gingivitis examination after having refrained from all oral hygiene procedures for 12 hours and from eating, drinking, or smoking for 4 hours. The population was comprised of healthy adult men and women 30 to 68 years of age. After the baseline examinations, qualifying subjects were randomized into two groups and assigned to one of the two test toothbrushes. All subjects were instructed to brush their teeth for 1 minute under supervision, after which they were again examined for supragingival plaque. They were then instructed to brush their teeth twice a day for 1 minute with their assigned toothbrush and a commercially available toothpaste (Colgate Cavity Protection Great Regular Flavor Fluoride Toothpaste) for the next 4 weeks. After 4 weeks, subjects returned to the clinical facility for a final gingivitis and plaque examination. Eighty-one subjects complied with the protocol and completed the 4-week clinical study. The results of the study indicated that the new manual toothbrush was statistically significantly effective in reducing gingivitis after 4 weeks and in removing plaque after a single toothbrushing and after 4 weeks of use. Also, the new manual toothbrush exhibited a statistically significant greater reduction in gingivitis and in gingivitis-related bleeding sites after 4 weeks of use as well as statistically significant greater plaque removal after a single toothbrushing and after 4 weeks of use, as compared to the Oral B Indicator toothbrush. This superior plaque-removal performance was found in separate analyses of the whole mouth, at interproximal surfaces, and at the gumline. PMID:15789980

  17. Balance between Angiopoietin-1 and Angiopoietin-2 Is in Favor of Angiopoietin-2 in Atherosclerotic Plaques with High Microvessel Density

    Microsoft Academic Search

    Simone Post; Wouter Peeters; Els Busser; Dennis Lamers; Joost P. G. Sluijter; Marie-José Goumans; Roel A. de Weger; Frans L. Moll; Pieter A. Doevendans; Gerard Pasterkamp; Aryan Vink

    2008-01-01

    Introduction: Atherosclerotic plaque microvessels are associated with plaque hemorrhage and rupture. The mechanisms underlying plaque angiogenesis are largely unknown. Angiopoietin (Ang)-1 and -2 are ligands of the endothelial receptor Tie-2. Ang-1 induces formation of stable vessels, whereas Ang-2 destabilizes the interaction between endothelial cells and their support cells. We studied the expression patterns of Ang-1 and -2 in relation to

  18. Risk of thrombosis in human atherosclerotic plaques: role of extracellular lipid, macrophage, and smooth muscle cell content

    Microsoft Academic Search

    M J Davies; P D Richardson; N Woolf; D R Katz; J Mann

    1993-01-01

    OBJECTIVE--To assess the size of the lipid pool and the number of smooth muscle cells and monocyte\\/macrophages in human aortic plaques that were intact and to compare the results with those in aortic plaques undergoing ulceration and thrombosis. DESIGN--The lipid pool was measured as a percentage of the total cross sectional area of the plaque. Immunohistochemistry was used to identify

  19. Plaque psoriasis vs. atopic dermatitis and lichen planus: a comparison for lesional T-cell subsets, epidermal proliferation and differentiation

    Microsoft Academic Search

    H. J. Bovenschen; M. M. B. Seijger

    2005-01-01

    BACKGROUND: T-cell infiltration in plaque psoriasis has recently been an important subject of investigation. Interestingly, comparative analyses of the disease-specific composition of the lesional T-cell infiltrate in plaque psoriasis and other inflammatory dermatoses have only sparsely been performed. OBJECTIVES: To compare plaque psoriasis vs. atopic dermatitis and lichen ruber planus with respect to T-cell subsets, epidermal proliferation and keratinization. PATIENTS

  20. A mechanistic analysis of the role of microcalcifications in atherosclerotic plaque stability: potential implications for plaque rupture

    PubMed Central

    Maldonado, Natalia; Kelly-Arnold, Adreanne; Vengrenyuk, Yuliya; Laudier, Damien; Fallon, John T.; Virmani, Renu; Cardoso, Luis

    2012-01-01

    The role of microcalcifications (?Calcs) in the biomechanics of vulnerable plaque rupture is examined. Our laboratory previously proposed (Ref. 44), using a very limited tissue sample, that ?Calcs embedded in the fibrous cap proper could significantly increase cap instability. This study has been greatly expanded. Ninety-two human coronary arteries containing 62 fibroatheroma were examined using high-resolution microcomputed tomography at 6.7-?m resolution and undecalcified histology with special emphasis on calcified particles <50 ?m in diameter. Our results reveal the presence of thousands of ?Calcs, the vast majority in lipid pools where they are not dangerous. However, 81 ?Calcs were also observed in the fibrous caps of nine of the fibroatheroma. All 81 of these ?Calcs were analyzed using three-dimensional finite-element analysis, and the results were used to develop important new clinical criteria for cap stability. These criteria include variation of the Young's modulus of the ?Calc and surrounding tissue, ?Calc size, and clustering. We found that local tissue stress could be increased fivefold when ?Calcs were closely spaced, and the peak circumferential stress in the thinnest nonruptured cap (66 ?m) if no ?Calcs were present was only 107 kPa, far less than the proposed minimum rupture threshold of 300 kPa. These results and histology suggest that there are numerous ?Calcs < 15 ?m in the caps, not visible at 6.7-?m resolution, and that our failure to find any nonruptured caps between 30 and 66 ?m is a strong indication that many of these caps contained ?Calcs. PMID:22777419

  1. Application of IR and NIR fiber optic imaging in thermographic and spectroscopic diagnosis of atherosclerotic vulnerable plaques: preliminary experience

    NASA Astrophysics Data System (ADS)

    Naghavi, Morteza; Khan, Tania; Gu, Bujin; Soller, Babs R.; Melling, Peter; Asif, Mohammed; Gul, Khawar; Madjid, Mohammad; Casscells, S. W.; Willerson, James T.

    2000-12-01

    Despite major advances in cardiovascular science and technology during the past three decades, approximately half of all myocardial infarctions and sudden deaths occur unexpectedly. It is widely accepted that coronary atherosclerotic plaques and thrombotic complications resulting from their rupture or erosion are the underlying causes of this major health problem. The majority of these vulnerable plaques exhibit active inflammation, a large necrotic lipid core, a thin fibrous cap, and confer a stenosis of less than 70%. These lesions are not detectable by stress testing or coronary angiography. Our group is exploring the possibility of a functional classification based on physiological variables such as plaque temperature, pH, oxygen consumption, lactate production etc. We have shown that heat accurately locates the inflamed plaques. We also demonstrated human atherosclerotic plaques are heterogeneous with regard to pH and hot plaques and are more likely to be acidic. To develop a nonsurgical method for locating the inflamed plaques, we are developing both IR fiber optic imaging and NIR spectroscopic systems in our laboratory to detect hot and acidic plaque in atherosclerotic arterial walls. Our findings introduce the possibility of an isolated/combined IR and NIR fiber optic catheter that can bring new insight into functional assessment of atherosclerotic plaque and thereby detection of active and inflamed lesions responsible for heart attacks and strokes.

  2. Distribution of ultrasonic radiofrequency signal amplitude detects lipids in atherosclerotic plaque of coronary arteries: an ex-vivo study

    PubMed Central

    Hara, Hisao; Tsunoda, Taro; Nemoto, Naohiko; Yokouchi, Itaru; Yamamoto, Masaya; Ono, Tsuyoshi; Moroi, Masao; Suzuki, Makoto; Sugi, Kaoru; Nakamura, Masato

    2008-01-01

    Background Accumulation of lipids within coronary plaques is an important process in disease progression. However, gray-scale intravascular ultrasound images cannot detect plaque lipids effectively. Radiofrequency signal analysis could provide more accurate information on preclinical coronary plaques. Methods We analyzed 29 zones of mild atheroma in human coronary arteries acquired at autopsy. Two histologic groups, i.e., plaques with a lipid core (group L) and plaques without a lipid core (group N), were analyzed by automatic calculation of integrated backscatter. One hundred regions of interest were set on the target zone. Radiofrequency signals from a 50 MHz transducer were digitized at 240 MHz with 12-bit resolution. The intensity of integrated backscatter and its distribution within each plaque were compared between the two groups. Results Although the mean backscatter was similar between the groups, intraplaque variation of backscatter and backscatter in the axial direction were larger in group L than in group N (p = 0.02). Conventional intravascular ultrasound showed extremely low sensitivity for lipid detection, despite a high specificity. In contrast, a cut-off value>32 for the total variance of integrated backscatter identified lipid-containing plaque with a high sensitivity (85%) and specificity (75%). Conclusion Compared with conventional imaging, assessment of the intraplaque distribution of integrated backscatter is more effective for detecting lipid. As coronary atheroma progresses, its composition becomes heterogeneous and multi-layered. This radiofrequency technique can portray complex plaque histology and can detect the early stage of plaque progression. PMID:18471302

  3. The relative effectiveness of six powered toothbrushes for dental plaque removal.

    PubMed

    Biesbrock, Aaron R; Walters, Patricia A; Bartizek, Robert D

    2002-01-01

    During the past three years, a number of new powered toothbrushes have been marketed in the United States. The objective of this study was to compare the single-use plaque removal efficacy of six powered toothbrushes: a new prototype (Crest SpinBrush Pro), Crest SpinBrush, Oral-B Battery, Colgate Motion, Oral-B 3-D Excel, and a Crest experimental toothbrush design. This study was a randomized, controlled, examiner-blind, six-period crossover design, which examined plaque removal with six powered toothbrushes following a single use in 26 subjects. Plaque was scored before and after brushing for one minute using the Turesky, et al. Modification of the Quigley-Hein Index. For statistical comparison, the plaque scores were averaged on a per-subject basis. Each subject had a single whole-mouth average score for baseline and for the exam following a one-minute brushing with their assigned toothbrush. The difference (baseline minus post-brushing) in average scores was calculated and analyzed using an analysis of covariance for a crossover design, with baseline whole-mouth average score as the covariate, and terms in the model for subjects, periods, and treatments. Mean baseline plaque scores ranged from 1.770-1.897 for the six toothbrush treatment groups and were not statistically significantly different. Using the analysis of covariance, with respect to all surfaces examined, the new prototype powered toothbrush (Crest SpinBrush Pro) delivered an adjusted mean difference between baseline and post-brushing plaque scores of 0.544, while the five remaining powered toothbrushes delivered an adjusted mean difference of 0.470-0.497. These results represent 10-16% greater plaque removal for the new prototype powered toothbrush. Overall, the six toothbrushes were not statistically significantly different (p = 0.199). However, results of unadjusted pair-wise comparisons conducted per the study protocol found that the new prototype powered toothbrush removed greater levels of plaque than the Oral-B 3-D Excel, Colgate Motion, and Crest experimental toothbrush (p = 0.028, p = 0.038, and p = 0.028, respectively). With respect to buccal and lingual surfaces, the new prototype powered toothbrush (Crest SpinBrush Pro) delivered very similar results relative to the control toothbrushes. Collectively, the results suggest that the new prototype powered toothbrush may offer enhanced plaque removal efficiency relative to the five other toothbrushes, and be at least as good as the five tested powered toothbrushes. PMID:12518489

  4. Potential role of ixekizumab in the treatment of moderate-to-severe plaque psoriasis

    PubMed Central

    Ren, Vicky; Dao, Harry

    2013-01-01

    Background Psoriasis is a debilitating autoimmune skin disease that affects 2%–3% of the world’s population. Patients with moderate-to-severe plaque psoriasis suffer from a decreased quality of life as well as comorbidities. Newer biological agents have been shown to be more effective than traditional therapies. In this article, we assess the potential role of ixekizumab, an anti-interleukin (IL)-17 antibody, in treating moderate-to-severe plaque psoriasis. Method We reviewed PubMed for articles regarding ixekizumab and the epidemiology and management of plaque psoriasis. Results In a Phase I clinical trial, treatment with ixekizumab resulted in both clinical and histopathologic improvement of psoriasis, which suggests that IL-17 may be a key driver in the pathogenesis of psoriasis. In a Phase II clinical trial, treatment with ixekizumab resulted in rapid clinical improvement of psoriasis, which lends further support to its role as an effective treatment for patients with chronic moderate-to-severe plaque psoriasis. Reductions in Psoriasis Area and Severity Index (PASI) score are comparable to those associated with currently marketed biologics. Conclusion Literature concerning the effects of ixekizumab on chronic moderate-to-severe plaque psoriasis is currently limited to two clinical trials. Results suggest that ixekizumab shows great therapeutic promise. However, more large-scale and long-term trials are needed to establish safety and efficacy. PMID:23515267

  5. A statin-loaded reconstituted high-density lipoprotein nanoparticle inhibits atherosclerotic plaque inflammation

    NASA Astrophysics Data System (ADS)

    Duivenvoorden, Raphaël; Tang, Jun; Cormode, David P.; Mieszawska, Aneta J.; Izquierdo-Garcia, David; Ozcan, Canturk; Otten, Maarten J.; Zaidi, Neeha; Lobatto, Mark E.; van Rijs, Sarian M.; Priem, Bram; Kuan, Emma L.; Martel, Catherine; Hewing, Bernd; Sager, Hendrik; Nahrendorf, Matthias; Randolph, Gwendalyn J.; Stroes, Erik S. G.; Fuster, Valentin; Fisher, Edward A.; Fayad, Zahi A.; Mulder, Willem J. M.

    2014-01-01

    Inflammation is a key feature of atherosclerosis and a target for therapy. Statins have potent anti-inflammatory properties but these cannot be fully exploited with oral statin therapy due to low systemic bioavailability. Here we present an injectable reconstituted high-density lipoprotein (rHDL) nanoparticle carrier vehicle that delivers statins to atherosclerotic plaques. We demonstrate the anti-inflammatory effect of statin-rHDL in vitro and show that this effect is mediated through the inhibition of the mevalonate pathway. We also apply statin-rHDL nanoparticles in vivo in an apolipoprotein E-knockout mouse model of atherosclerosis and show that they accumulate in atherosclerotic lesions in which they directly affect plaque macrophages. Finally, we demonstrate that a 3-month low-dose statin-rHDL treatment regimen inhibits plaque inflammation progression, while a 1-week high-dose regimen markedly decreases inflammation in advanced atherosclerotic plaques. Statin-rHDL represents a novel potent atherosclerosis nanotherapy that directly affects plaque inflammation.

  6. Neuronal driven pre-plaque inflammation in a transgenic rat model of Alzheimer's disease.

    PubMed

    Hanzel, Cecilia E; Pichet-Binette, Alexa; Pimentel, Luisa S B; Iulita, M Florencia; Allard, Simon; Ducatenzeiler, Adriana; Do Carmo, Sonia; Cuello, A Claudio

    2014-10-01

    Chronic brain inflammation is associated with Alzheimer's disease (AD) and is classically attributed to amyloid plaque deposition. However, whether the amyloid pathology can trigger early inflammatory processes before plaque deposition remains a matter of debate. To address the possibility that a pre-plaque inflammatory process occurs, we investigated the status of neuronal, astrocytic, and microglial markers in pre- and post-amyloid plaque stages in a novel transgenic rat model of an AD-like amyloid pathology (McGill-R-Thy1-APP). In this model, we found a marked upregulation of several classical inflammatory markers such as COX-2, IL-1?, TNF-?, and fractalkine (CX3CL1) in the cerebral cortex and hippocampus. Interestingly, many of these markers were highly expressed in amyloid beta-burdened neurons. Activated astrocytes and microglia were associated with these A?-burdened neurons. These findings confirm the occurrence of a proinflammatory process preceding amyloid plaque deposition and suggest that A?-burdened neurons play a crucial role in initiating inflammation in AD. PMID:24831823

  7. A Statin-Loaded Reconstituted High-Density Lipoprotein Nanoparticle Inhibits Atherosclerotic Plaque Inflammation

    PubMed Central

    Duivenvoorden, Raphaël; Tang, Jun; Cormode, David P.; Mieszawska, Aneta J.; Izquierdo-Garcia, David; Ozcan, Canturk; Otten, Maarten J.; Zaidi, Neeha; Lobatto, Mark E.; van Rijs, Sarian M.; Priem, Bram; Kuan, Emma L.; Martel, Catherine; Hewing, Bernd; Sager, Hendrik; Nahrendorf, Matthias; Randolph, Gwendalyn J.; Stroes, Erik S.G.; Fuster, Valentin; Fisher, Edward A.; Fayad, Zahi A.; Mulder, Willem J.M.

    2014-01-01

    Inflammation is a key feature of atherosclerosis and a target for therapy. Statins have potent anti-inflammatory properties but these cannot be fully exploited with oral statin therapy due to low systemic bioavailability. Here we present an injectable reconstituted high-density lipoprotein (rHDL) nanoparticle carrier vehicle that delivers statins to atherosclerotic plaques. We demonstrate the anti-inflammatory effect of statin-rHDL in vitro and show this effect is mediated through inhibition of the mevalonate pathway. We also apply statin-rHDL nanoparticles in vivo in an apolipoprotein E-knockout mouse model of atherosclerosis and show they accumulate in atherosclerotic lesions where they directly affect plaque macrophages. Finally we demonstrate that a three-month low-dose statin-rHDL treatment regimen inhibits plaque inflammation progression, while a one-week high-dose regimen markedly decreases inflammation in advanced atherosclerotic plaques. Statin-rHDL represents a novel potent atherosclerosis nanotherapy that directly affects plaque inflammation. PMID:24445279

  8. Male Gender and Arterial Hypertension are Plaque Predictors at Coronary Computed Tomography Angiography

    PubMed Central

    Oliveira, Joselina Luzia Menezes; Hirata, Mario Hiroyuki; Sousa, Amanda Guerra de Moraes Rego; Gabriel, Fabíola Santos; Hirata, Thiago Dominguez Crespo; Tavares, Irlaneide da Silva; Melo, Luiza Dantas; Dória, Fabiana de Santana; Sousa, Antônio Carlos Sobral; Pinto, Ibraim Masciarelli Francisco

    2015-01-01

    Background Systemic Arterial Hypertension (SAH) is one of the main risk factors for Coronary Artery Disease (CAD), in addition to male gender. Differences in coronary artery lesions between hypertensive and normotensive individuals of both genders at the Coronary Computed Tomography Angiography (CCTA) have not been clearly determined. Objective To Investigate the calcium score (CS), CAD extent and characteristics of coronary plaques at CCTA in men and women with and without SAH. Methods Prospective cross-sectional study of 509 patients undergoing CCTA for CAD diagnosis and risk stratification, from November 2011 to December 2012, at Instituto de Cardiologia Dante Pazzanese. Individuals were stratified according to gender and subdivided according to the presence (HT +) or absence (HT-) of SAH. Results HT+ women were older (62.3 ± 10.2 vs 57.8 ± 12.8, p = 0.01). As for the assessment of CAD extent, the HT+ individuals of both genders had significant CAD, although multivessel disease is more frequent in HT + men. The regression analysis for significant CAD showed that age and male gender were the determinant factors of multivessel disease and CS ? 100. Plaque type analysis showed that SAH was a predictive risk factor for partially calcified plaques (OR = 3.9). Conclusion Hypertensive men had multivessel disease more often than women. Male gender was a determinant factor of significant CAD, multivessel disease, CS ? 100 and calcified and partially calcified plaques, whereas SAH was predictive of partially calcified plaques. PMID:25861034

  9. CTRP9 enhances carotid plaque stability by reducing pro-inflammatory cytokines in macrophages.

    PubMed

    Li, Jun; Zhang, Peng; Li, Tingting; Liu, Yawei; Zhu, Qing; Chen, Tongshuai; Liu, Tianjiao; Huang, Chengmin; Zhang, Jianning; Zhang, Yun; Guo, Yuan

    2015-03-20

    The aim of this study was to investigate whether C1q/TNF-related protein 9 (CTRP9) could stabilize the mature plaques by targeting macrophages in the apolipoprotein E knockout (ApoE KO) mice model. In vivo, the mice were subjected to high-fat diet and constrictive collars on the right carotid artery for eight weeks, a lentiviral vectors expressing CTRP9 (LV-CTRP9) or green fluorescence protein (LV-eGFP) as a control was intravenously injected into ApoE KO mice. Delivery of LV-CTRP9 resulted in low contents of macrophages and lipids, and high contents of collagen and vascular smooth muscle cells in the carotid mature plaques. In addition, CTRP9 also decreased pro-inflammatory cytokines in mature plaques. In vitro, RAW264.7 macrophages were pretreated with or without LV-CTRP9 transfection, and then stimulated with oxLDL (50 ?g/mL). We found that the expression levels of tumor necrosis factor-? (TNF-?) and monocyte chemoattractant protein 1 (MCP-1) in the LV-CTRP9 group were significantly lower than those in the LV-eGFP group after exposure to oxLDL. The present data indicate that CTRP9 overexpression enhances the plaque stability in ApoE KO mice by reducing pro-inflammatory cytokines in macrophages. Our study suggests that the therapeutic approaches to enhance CTRP9 production could be valuable for plaque stabilization. PMID:25701788

  10. Effect of Transmural Transport Properties on Atheroma Plaque Formation and Development.

    PubMed

    Cilla, M; Martínez, M A; Peña, E

    2015-07-01

    We propose a mathematical model of atheroma plaque initiation and early development in coronary arteries using anisotropic transmural diffusion properties. Our current approach is on the process on plaque initiation and intimal thickening rather than in severe plaque progression and rupture phenomena. The effect of transport properties, in particular the anisotropy of diffusion properties of the artery, on plaque formation and development is investigated using the proposed mathematical model. There is not a strong influence of the anisotropic transmural properties on LDL, SMCs and collagen distribution and concentrations along the artery. On the contrary, foam cells distribution strongly depends on the value of the radial diffusion coefficient of the substances [Formula: see text] and the ratio [Formula: see text]. Decreasing [Formula: see text] or diffusion coefficients ratio means a higher concentration of the foam cells close to the intima. Due to the fact that foam cells concentration is associated to the necrotic core formation, the final distribution of foam cells is critical to evolve into a vulnerable or fibrotic plaque. PMID:25814436

  11. Mapping the Genetic Determinants of Pathogenicity and Plaque Phenotype in Swine Vesicular Disease Virus

    PubMed Central

    Kanno, Toru; Mackay, David; Inoue, Toru; Wilsden, Ginette; Yamakawa, Makoto; Yamazoe, Reiko; Yamaguchi, Shigeo; Shirai, Junsuke; Kitching, Paul; Murakami, Yosuke

    1999-01-01

    A series of recombinant viruses were constructed using infectious cDNA clones of the virulent J1’73 (large plaque phenotype) and the avirulent H/3’76 (small plaque phenotype) strains of swine vesicular disease virus to identify the genetic determinants of pathogenicity and plaque phenotype. Both traits could be mapped to the region between nucleotides (nt) 2233 and 3368 corresponding to the C terminus of VP3, the whole of VP1, and the N terminus of 2A. In this region, there are eight nucleotide differences leading to amino acid changes between the J1’73 and the H/3’76 strains. Site-directed mutagenesis of individual nucleotides from the virulent to the avirulent genotype and vice versa indicated that A at nt 2832, encoding glycine at VP1-132, and G at nt 3355, encoding arginine at 2APRO-20, correlated with a large-plaque phenotype and virulence in pigs, irrespective of the origin of the remainder of the genome. Of these two sites, 2APRO-20 appeared to be the dominant determinant for the large-plaque phenotype but further studies are required to elucidate their relative importance for virulence in pigs. PMID:10074117

  12. Measurement of proteases in human subgingival dental plaque by fluorescence polarization.

    PubMed

    Grys, E L; Schade, S Z; Cohen, M E; Geivelis, M; Robinson, P J; Simonson, L G

    2000-12-01

    Fluorescence polarization (FP) was examined as a rapid quantitative method to assay the proteases in subgingival plaque. Protease activity was measured by a decrease in FP at 0.5-min intervals over 5 min, using BODIPY-alpha-casein, a protein substrate. To quantitate activity, the least absolute deviation (LAD) slope for each assay was determined. Protease activity increased with the quantity of plaque (r=0.416, P<0.001). Of the 208 subgingival plaque samples, 87 contained detectable protease activity, with a mean of about 4 microg trypsin equivalents above a general background of 1 microg per site. The mean plaque protease activity of 89 paired samples from 15 individuals had decreased by 1.1 microg trypsin equivalents per site when measured at 8 months after tooth scaling and root planing (P<0.01). Most isolates of Porphyromonas gingivalis, Treponema denticola, Prevotella nigrescens, and Prevotella intermedia implicated in the pathogenesis of adult periodontitis exhibited high activity in the FP assay. The assay is rapid, quantitative and requires only one-tenth of the plaque sampled using a single pass with a Gracey curette at a single tooth site. PMID:11084150

  13. Quantitative assessment of MS plaques and brain atrophy in multiple sclerosis using semiautomatic segmentation method

    NASA Astrophysics Data System (ADS)

    Heinonen, Tomi; Dastidar, Prasun; Ryymin, Pertti; Lahtinen, Antti J.; Eskola, Hannu; Malmivuo, Jaakko

    1997-05-01

    Quantitative magnetic resonance (MR) imaging of the brain is useful in multiple sclerosis (MS) in order to obtain reliable indices of disease progression. The goal of this project was to estimate the total volume of gliotic and non gliotic plaques in chronic progressive multiple sclerosis with the help of a semiautomatic segmentation method developed at the Ragnar Granit Institute. Youth developed program running on a PC based computer provides de displays of the segmented data, in addition to the volumetric analyses. The volumetric accuracy of the program was demonstrated by segmenting MR images of fluid filed syringes. An anatomical atlas is to be incorporated in the segmentation system to estimate the distribution of MS plaques in various neural pathways of the brain. A total package including MS plaque volume estimation, estimation of brain atrophy and ventricular enlargement, distribution of MS plaques in different neural segments of the brain has ben planned for the near future. Our study confirmed that total lesion volumes in chronic MS disease show a poor correlation to EDSS scores but show a positive correlation to neuropsychological scores. Therefore accurate total volume measurements of MS plaques using the developed semiautomatic segmentation technique helped us to evaluate the degree of neuropsychological impairment.

  14. Effects of a Novel Dental Gel on Plaque and Gingivitis: A Comparative Study

    PubMed Central

    Dadkhah, M; Chung, NE; Ajdaharian, J; Wink, C; Klokkevold, P; Wilder-Smith, P

    2015-01-01

    Objectives The goal of this prospective, randomized, controlled, double-blinded study was to evaluate the effects of a novel dental gel on plaque and gingival health. The dental gel was designed to (1) break up and prevent re-accumulation of microbial biofilm, and (2) inhibit metal mediated inflammation. Materials and Methods Twenty-five subjects with moderate gingival inflammation (Löe and Silness Gingival Index ?2) and pocket depths <4 were randomly assigned to brush twice daily for 21 days with the test or the control dental gel. On Days 0, 7, 14 and 21, plaque levels (Quigley-Hein, Turesky Modification Plaque Index), gingival inflammation (Löe and Silness Gingival Index) and gingival bleeding (modified Sulcus Bleeding Index) were determined by one blinded, investigator using a pressure sensitive probe. Results After 3 weeks, all 3 clinical indices were significantly improved in both groups (P<0.05) and significantly lower in the test group (P<0.05). Conclusion The novel dental gel formulation was provided effective plaque control and reduced gingival inflammation. Clinical Relevance A novel dentifrice formulation may be an effective tool for plaque removal and maintaining gingival health.

  15. Plaque Size Reduction as a Measure of Viral Cell-Mediated Immunity

    PubMed Central

    Simmons, Richard L.; Centifanto, Ysolina; Kaufman, Herbert E.

    1974-01-01

    This new assay of viral cell-mediated immunity is sensitive, reproducible, and in many ways resembles the in vivo state. The spread of herpes simplex virus between adjacent monolayer cells was inhibited in the presence of spleen cells from guinea pigs sensitized to that virus. This in vitro control of viral growth was quantified by determining plaque size in monolayers to which were added sensitized spleen cells as opposed to nonsensitized or no spleen cells. The simple measurement of plaque size reduction as an in vitro test of viral cell-mediated immunity is described. In addition to correlating highly with skin testing and macrophage migration inhibition as a test of viral cell-mediated immunity, the ability of sensitized spleen cells to reduce plaque size developed by day 7, paralleling the onset of delayed cutaneous hypersensitivity. The specificity of this lymphocyte-mediated interaction was demonstrated by the inability of herpes simplex virus-sensitized spleen cells to alter the growth of vaccinia virus in cell culture. A ratio of sensitized spleen cells to monolayer cells of 6:1 resulted in significant plaque size reduction on both HEp-2 and conjunctiva monolayers. The data presented demonstrate the potential usefulness of plaque size reduction as a technically simple, specific, and more direct measure of cellular antiviral activity. PMID:16558085

  16. A comparison of natural product, triclosan and chlorhexidine mouthrinses on 4-day plaque regrowth.

    PubMed

    Moran, J; Addy, M; Roberts, S

    1992-09-01

    There is a continuing search for ingredients to enhance the chemical plaque inhibitory action of oral hygiene products. Sanguinarine, other natural extracts and triclosan have already been used in products. The aim of this study was to evaluate a number of triclosan and natural product rinses for effects on plaque regrowth. In particular, the influence of other rinse components were assessed, notably sodium lauryl sulphate (SLS) and zinc. The study was a randomised, blind, 9-cell cross-over design to measure the effects of each rinse on 4-day plaque regrowth from a zero baseline. 15 volunteers rinsed 2x daily with each product and plaque was recorded by area and score. The 0.2% chlorhexidine rinse (positive control) was significantly more effective, and the saline rinse (negative control) significantly less effective, than other rinses. Sanguinarine alone was little different from saline and the addition of zinc made a modest improvement in activity. The 3 triclosan/SLS rinses were more effective than the sanguinarine rinses but similar to their minus triclosan control rinse. A natural product/SLS experimental rinse was second to chlorhexidine and, in many analyses, significantly better than all other rinses, but caused some oral erosions. The results indicate that the plaque inhibitory properties of basic ingredients such as SLS may be difficult to enhance or surpass. However, the possible range of recipes, particularly using natural ingredients, provides scope for research and development in the field of oral hygiene products. PMID:1447382

  17. Effect of shear stress alteration on atherosclerotic plaque vulnerability in cholesterol-fed rabbits.

    PubMed

    den Dekker, Wijnand K; Tempel, Dennie; Speelman, Lambert; Huizingh, Jeroen; Ramos, Allan; Gijsen, Frank J; Wentzel, Jolanda J; Cheng, Caroline; Duckers, Henricus J

    2014-05-14

    Previously, we created an experimental murine model for the induction of vulnerable plaque (VP). Although this murine model offers the opportunity to study the different molecular biological pathways that regulate plaque destabilization, the size of the animals severely limits the use of the model for in vivo diagnostics and percutaneous interventions. This study aimed to create a VP model in the rabbit, based on the murine model, to aid the assessment and development of novel diagnostic and interventional tools. New Zealand white rabbits were fed on a 2% cholesterol diet. After 1 week, a shear stress-altering device was implanted around the right carotid artery. Twelve weeks after cast placement, the carotid artery was isolated and processed for (immuno-)histological analysis to evaluate the presence of a VP phenotype. Atherosclerotic plaques with high lipid and macrophage content, low vascular smooth muscle cell content and intimal neovascularization were located upstream and downstream of the cast. The plaques lacked a significant necrotic core. In conclusion, we were able to create atherosclerotic plaques with a phenotype beyond that of a fatty streak, with a high percentage of lipids and macrophages, a thick cap with some vascular smooth muscle cells and neovascularization. However, as there was only a small necrotic core, the overall phenotype seems less vulnerable as compared to the thin fibrous cap atheroma in patients. PMID:24829311

  18. Association of Coronary Wall Shear Stress With Atherosclerotic Plaque Burden, Composition, and Distribution in Patients With Coronary Artery Disease

    PubMed Central

    Eshtehardi, Parham; McDaniel, Michael C.; Suo, Jin; Dhawan, Saurabh S.; Timmins, Lucas H.; Binongo, José Nilo G.; Golub, Lucas J.; Corban, Michel T.; Finn, Aloke V.; Oshinski, John N.; Quyyumi, Arshed A.; Giddens, Don P.; Samady, Habib

    2012-01-01

    Background Extremes of wall shear stress (WSS) have been associated with plaque progression and transformation, which has raised interest in the clinical assessment of WSS. We hypothesized that calculated coronary WSS is predicted only partially by luminal geometry and that WSS is related to plaque composition. Methods and Results Twenty?seven patients with coronary artery disease underwent virtual histology intravascular ultrasound and Doppler velocity measurement for computational fluid dynamics modeling for WSS calculation in each virtual histology intravascular ultrasound segment (N=3581 segments). We assessed the association of WSS with plaque burden and distribution and with plaque composition. WSS remained relatively constant across the lower 3 quartiles of plaque burden (P=0.08) but increased in the highest quartile of plaque burden (P<0.001). Segments distal to lesions or within bifurcations were more likely to have low WSS (P<0.001). However, the majority of segments distal to lesions (80%) and within bifurcations (89%) did not exhibit low WSS. After adjustment for plaque burden, there was a negative association between WSS and percent necrotic core and calcium. For every 10 dynes/cm2 increase in WSS, percent necrotic core decreased by 17% (P=0.01), and percent dense calcium decreased by 17% (P<0.001). There was no significant association between WSS and percent of fibrous or fibrofatty plaque components (P=NS). Conclusions In patients with coronary artery disease: (1) Luminal geometry predicts calculated WSS only partially, which suggests that detailed computational techniques must be used to calculate WSS. (2) Low WSS is associated with plaque necrotic core and calcium, independent of plaque burden, which suggests a link between WSS and coronary plaque phenotype. (J Am Heart Assoc. 2012;1:e002543 doi: 10.1161/JAHA.112.002543.) PMID:23130168

  19. Clinical effect of a gel containing Lippia sidoides on plaque and gingivitis control

    PubMed Central

    Pereira, Sérgio Luis da Silva; Praxedes, Yuri Carvalho Machado; Bastos, Thiago Catunda; Alencar, Phillipe Nogueira Barbosa; da Costa, Flávio Nogueira

    2013-01-01

    Objective: This parallel controlled clinical trial evaluated the effect of a gel containing Lippia sidoides essential oil on plaque and gingivitis control. Methods: Thirty patients (n=30) were randomly selected and allocated into three groups: Lippia sidoides (LS, n=10), chlorhexidine (CLX, n=10) or placebo (control, n=10). Plaque and bleeding index were recorded at baseline and after three months. All volunteers were instructed to brush with the gel three times a day throughout the experiment period. Results: There was a significant reduction on plaque and gingivitis in the test groups (P<.05), but no statistically significant difference was observed between them (P>.05). Conclusion: A gel preparation containing 10% Lippia sidoides essential oil was an efficient herbal antiplaque and antigingivitis agent. PMID:23408652

  20. In vivo Raman spectral pathology of human atherosclerosis and vulnerable plaque

    NASA Astrophysics Data System (ADS)

    Motz, Jason T.; Fitzmaurice, Maryann; Miller, Arnold; Gandhi, Saumil J.; Haka, Abigail S.; Galindo, Luis; Dasari, Ramachandra R.; Kramer, John R., Jr.; Feld, Michael S.

    2006-03-01

    The rupture of vulnerable atherosclerotic plaque accounts for the majority of clinically significant acute cardiovascular events. Because stability of these culprit lesions is directly related to chemical and morphological composition, Raman spectroscopy may be a useful technique for their study. Recent developments in optical fiber probe technology have allowed for the real-time in vivo Raman spectroscopic characterization of human atherosclerotic plaque demonstrated in this work. We spectroscopically examine 74 sites during carotid endarterectomy and femoral artery bypass surgeries. Of these, 34 are surgically biopsied and examined histologically. Excellent signal-to-noise ratio spectra are obtained in only 1 s and fit with an established model, demonstrating accurate tissue characterization. We also report the first evidence that Raman spectroscopy has the potential to identify vulnerable plaque, achieving a sensitivity and specificity of 79 and 85%, respectively. These initial findings indicate that Raman spectroscopy has the potential to be a clinically relevant diagnostic tool for studying cardiovascular disease.

  1. Computer-implemented system and method for automated and highly accurate plaque analysis, reporting, and visualization

    NASA Technical Reports Server (NTRS)

    Kemp, James Herbert (Inventor); Talukder, Ashit (Inventor); Lambert, James (Inventor); Lam, Raymond (Inventor)

    2008-01-01

    A computer-implemented system and method of intra-oral analysis for measuring plaque removal is disclosed. The system includes hardware for real-time image acquisition and software to store the acquired images on a patient-by-patient basis. The system implements algorithms to segment teeth of interest from surrounding gum, and uses a real-time image-based morphing procedure to automatically overlay a grid onto each segmented tooth. Pattern recognition methods are used to classify plaque from surrounding gum and enamel, while ignoring glare effects due to the reflection of camera light and ambient light from enamel regions. The system integrates these components into a single software suite with an easy-to-use graphical user interface (GUI) that allows users to do an end-to-end run of a patient record, including tooth segmentation of all teeth, grid morphing of each segmented tooth, and plaque classification of each tooth image.

  2. The neuroimmune guidance cue netrin-1 promotes atherosclerosis by inhibiting the emigration of macrophages from plaques.

    PubMed

    van Gils, Janine M; Derby, Merran C; Fernandes, Luciana R; Ramkhelawon, Bhama; Ray, Tathagat D; Rayner, Katey J; Parathath, Sajesh; Distel, Emilie; Feig, Jessica L; Alvarez-Leite, Jacqueline I; Rayner, Alistair J; McDonald, Thomas O; O'Brien, Kevin D; Stuart, Lynda M; Fisher, Edward A; Lacy-Hulbert, Adam; Moore, Kathryn J

    2012-02-01

    Atherosclerotic plaque formation is fueled by the persistence of lipid-laden macrophages in the artery wall. The mechanisms by which these cells become trapped, thereby establishing chronic inflammation, remain unknown. Here we found that netrin-1, a neuroimmune guidance cue, was secreted by macrophages in human and mouse atheroma, where it inactivated the migration of macrophages toward chemokines linked to their egress from plaques. Acting via its receptor, UNC5b, netrin-1 inhibited the migration of macrophages directed by the chemokines CCL2 and CCL19, activation of the actin-remodeling GTPase Rac1 and actin polymerization. Targeted deletion of netrin-1 in macrophages resulted in much less atherosclerosis in mice deficient in the receptor for low-density lipoprotein and promoted the emigration of macrophages from plaques. Thus, netrin-1 promoted atherosclerosis by retaining macrophages in the artery wall. Our results establish a causative role for negative regulators of leukocyte migration in chronic inflammation. PMID:22231519

  3. [Erionite-induced pleural plaques. Exposition to urban pollution in a female Turkish migrant in Germany].

    PubMed

    Gräsel, B; Kaya, A; Stahl, U; Rauber, K; Kuntz, C

    2008-06-01

    Erionite is a zeolite mineral of volcanic origin which contains no asbestos. It is found in different regions of the world, including southeast Turkey in ash and dust, from which it can cause inflammatory pleural plaques or malignant pleural mesothelioma (MPM). We report a female Turkish migrant exposed to urban pollution in her home country who decades later suffered from pleural plaques with a nonspecific chronic inflammatory disease. The differential diagnosis of inflammatory pleural plaques was assumed radiologically and confirmed by video-assisted thoracoscopic biopsy. Short-term clinical and radiologic control of the patient will be necessary because of the risk of MPM. For epidemiologic considerations discussed referring to current literature, a growing incidence of this type of disease in migrants from high-risk areas must be reckoned with in Germany, even without exposition to asbestos. PMID:18506411

  4. Totally extradural spinal en plaque meningiomas – Diagnostic dilemmas and treatment strategies

    PubMed Central

    Savardekar, Amey; Chatterjee, Debarshi; Chatterjee, Debajyoti; Dhandapani, Sivashanmugam; Mohindra, Sandeep; Salunke, Pravin

    2014-01-01

    Background: Meningiomas are the second most common intraspinal tumors, constituting ~25% of all intraspinal tumors; however, in the context of extradural spinal lesions, the diagnosis of meningioma is an uncommon one. Purely extradural spinal meningiomas, especially of the en plaque variety, frequently mimic metastatic disease and may result in inadequate therapy. Case Description: We report two cases of totally extradural en-plaque meningiomas of the spine, one each in the cervical and dorsal spine. We present the significant diagnostic dilemmas posed by these cases and discuss the pathogenesis, treatment strategies, and long-term behavior of these uncommon lesions. Conclusion: Attention needs to be drawn to this dangerous preoperative and intraoperative misinterpretation. Intraoperative histopathology support for correct identification, gross total resection at surgery, inclusion of a durotomy to rule out intradural extension, and long-term follow-up are cornerstones for successful management of totally extradural en plaque spinal meningiomas. PMID:25289148

  5. Fully automated and adaptive detection of amyloid plaques in stained brain sections of Alzheimer transgenic mice.

    PubMed

    Feki, Abdelmonem; Teboul, Olivier; Dubois, Albertine; Bozon, Bruno; Faure, Alexis; Hantraye, Philippe; Dhenain, Marc; Delatour, Benoit; Delzescaux, Thierry

    2007-01-01

    Automated detection of amyloid plaques (AP) in post mortem brain sections of patients with Alzheimer disease (AD) or in mouse models of the disease is a major issue to improve quantitative, standardized and accurate assessment of neuropathological lesions as well as of their modulation by treatment. We propose a new segmentation method to automatically detect amyloid plaques in Congo Red stained sections based on adaptive thresholds and a dedicated amyloid plaque/tissue modelling. A set of histological sections focusing on anatomical structures was used to validate the method in comparison to expert segmentation. Original information concerning global amyloid load have been derived from 6 mouse brains which opens new perspectives for the extensive analysis of such a data in 3-D and the possibility to integrate in vivo-post mortem information for diagnosis purposes. PMID:18044661

  6. Technical aspects of nuclear microprobe analysis of senile plaques from alzheimer patients

    NASA Astrophysics Data System (ADS)

    Larsson, N. P.-O.; Tapper, U. A. S.; Sturesson, K.; Odselius, R.; Brun, A.

    1990-04-01

    Alzheimer's disease, a common form of senile dementia, has been proposed to be caused by aluminium. One of the interesting structures to be studied, senile plaque cores in the brain, have centres of only about 10 ?m. We have investigated the possibility of applying nuclear microprobes to sections containing senile plaques. An alternative staining procedure, TMToluidin blue staining using a spray technique, is also presented. An outline is given of a procedure for preparing senile plaque specimens for nuclear microprobe analysis. This includes a technique for accurate ion beam positioning, utilizing electron microscopy-grids. The subject may be of general interest since sample preparation is one of the most important aspects in microprobe analysis of biological matter.

  7. Antibacterial activity of aqueous extracts of Indian chewing sticks on dental plaque: An in vitro study.

    PubMed

    Rao, Dola Srinivasa; Penmatsa, Tanuja; Kumar, Alapati Kranthi; Reddy, M Narendra; Gautam, Nalam Sai; Gautam, Nalam Radhika

    2014-07-01

    The anti-microbial efficacy of aqueous extracts of Indian chewing sticks against different kinds of plaque bacteria in vitro was investigated. Supra-gingival plaque is cultured and subjected to the antibacterial activity of the aqueous extracts of chewing sticks (Neem, Acacia, Pongamia glabra, Achyranthes aspera, Streblus asper) separately. The results of the study demonstrate that all the five chewing sticks under study possess inhibitory potential against bacteria present in dental plaque mainly on aerobes. The antibacterial efficacy of aqueous extracts has antibacterial effects and could be used as a therapeutic agent and therefore, it appears to be potent anti-microbial agents that could be considered as a medicinal plant. Results of this study showed chewing sticks contained antibacterial agents, but the concentration and composition of the active substances differed among the plants. PMID:25210357

  8. The Association of Brachial Artery Diameter with Noncalcified Coronary Plaque Burden in Apparently Healthy Individuals

    PubMed Central

    Vaidya, Dhananjay; Kral, Brian G.; Yanek, Lisa R; Moy, Taryn F.; Fishman, Elliot K.; Becker, Diane M.; Becker, Lewis C.

    2015-01-01

    Objective Coronary atherosclerosis has been associated with systemic arterial remodeling even in non-atherosclerotic vessels. However it is not known whether systemic remodeling is differentially associated with the cumulative atherosclerotic process, reflected by putatively quiescent calcified plaque (CP) or with active atherosclerosis consisting of non-calcified plaque (NCP). We thus examined the association of brachial artery diameter (BAD), an artery which does not suffer clinical atherosclerosis, with the presence and the extent of coronary CP and NCP. Methods We studied 688 apparently healthy, asymptomatic participants from 350 families with a history of early-onset coronary artery disease (<60 years of age) measuring CAD risk factors and coronary plaque using dual-source CT angiography. Plaque volumes were quantified using a validated automated method. BAD was measured during diastole using B-mode ultrasound. The association of resting BAD with any detectable plaque, and log-transformed CP and NCP volumes if detectable, was tested using Generalized Estimating Equations (GEE) adjusted for age, sex, race, current smoking, diabetes, hypertension, body mass index, non-HDL and HDL-cholesterol. Results Higher quintiles of BAD were associated with greater age and male sex (both p <0.001). In fully adjusted analysis, CP volume was not associated with BAD (p=0.65) but 1 ml greater NCP volume was associated with 0.65 mm larger BAD (p=0.027). Conclusion Our results suggest that systemic arterial remodeling of non-atherosclerotic arteries is a dynamic process that is correlated with the extent of putatively active atherosclerotic processes in distant beds, but not inactive accumulated plaque burden. PMID:24077324

  9. Osteoprotegerin, Pericytes and Bone-Like Vascular Calcification Are Associated with Carotid Plaque Stability

    PubMed Central

    Davaine, Jean-Michel; Quillard, Thibaut; Brion, Régis; Lapérine, Olivier; Guyomarch, Béatrice; Merlini, Thierry; Chatelais, Mathias; Guilbaud, Florian; Brennan, Meadhbh Áine; Charrier, Céline; Heymann, Dominique; Gouëffic, Yann; Heymann, Marie-Françoise

    2014-01-01

    Background and Purpose Vascular calcification, recapitulating bone formation, has a profound impact on plaque stability. The aim of the present study was to determine the influence of bone-like vascular calcification (named osteoid metaplasia?=?OM) and of osteoprotegerin on plaque stability. Methods Tissue from carotid endarterectomies were analysed for the presence of calcification and signs of vulnerability according to AHA grading system. Osteoprotegerin (OPG), pericytes and endothelial cells were sought using immuno-histochemistry. Symptoms and preoperative imaging findings (CT-scan, MRI and Doppler-scan) were analyzed. Human pericytes were cultured to evaluate their ability to secrete OPG and to influence mineralization in the plaque. Results Seventy-three carotid plaques (49 asymptomatic and 24 symptomatic) were harvested. A significantly higher presence of OM (18.4% vs 0%, p<0.01), OPG (10.2% of ROI vs 3.4% of ROI, p<0.05) and pericytes (19% of ROI vs 3.8% of ROI, p<0.05) were noted in asymptomatic compared to symptomatic plaques. Consistently, circulating OPG levels were higher in the plasma of asymptomatic patients (3.2 ng/mL vs 2.5 ng/mL, p?=?0.05). In vitro, human vascular pericytes secreted considerable amounts of OPG and underwent osteoblastic differentiation. Pericytes also inhibited the osteoclastic differentiation of CD14+ cells through their secretion of OPG. Conclusions OPG (intraplaque an plasmatic) and OM are associated with carotid plaque stability. Pericytes may be involved in the secretion of intraplaque OPG and in the formation of OM. PMID:25259713

  10. Effects of Stent Design and Atherosclerotic Plaque Composition on Arterial Wall Biomechanics

    PubMed Central

    Timmins, Lucas H.; Meyer, Clark A.; Moreno, Michael R.; Moore, James E.

    2008-01-01

    Purpose: To examine the solid mechanical effects of varying stent design and atherosclerotic plaque stiffness on the biomechanical environment induced in a diseased artery wall model. Methods: Computational modeling techniques were employed to investigate the final radius of the lumen and artery wall stresses after stent implantation. Two stent designs were studied (one stiff and one less stiff). The stenotic artery was modeled as an axisymmetrical diseased vessel with a 20% stenosis by diameter. The material properties of the diseased tissue in the artery models varied. Atherosclerotic plaques half as stiff (0.5×), of equal stiffness (1.0×), or twice as stiff (2.0×) as the artery wall were investigated. Results: Final lumen radius was dependent on stent design, and the stiffer stent deformed the artery to an approximately 10% greater radius than the more compliant design. Alternatively, circumferential stress levels were dependent on both stent design and plaque material properties. Overall, the stiffer stent subjected the artery wall to much higher stress values than the more compliant design, with differences in peak values of 0.50, 0.31, and 0.09 MPa for the 2.0×, 1.0×, and 0.5× stiff plaques, respectively. Conclusion: Evidence suggests that a judicious choice of stent design can minimize stress while maintaining a patent lumen in stenotic arteries. If confronted with a rigid, calcified plaque, stent design is more important, as design differences can impose dramatically different stress fields, while still providing arterial patency. Alternatively, stent design is not as much of an issue when treating a soft, lipid-laden plaque, as stress fields do not vary significantly among stent designs. PMID:19090628

  11. Quantification of new structural features of coronary plaques by computational post-hoc analysis of virtual histology-intravascular ultrasound images.

    PubMed

    Papaioannou, Theodore G; Schizas, Dimitrios; Vavuranakis, Manolis; Katsarou, Ourania; Soulis, Dimitrios; Stefanadis, Christodoulos

    2014-01-01

    Cardiovascular disease and complications are often mediated by the development and rupture of atherosclerotic plaques. Plaque composition is a major factor that determines plaque vulnerability. Intravascular ultrasound (IVUS) and spectral analysis of the radio frequency signal provide an in vivo tissue characterisation of atherosclerotic plaques, known as virtual histology (VH-IVUS). In VH-IVUS analysis, four histological tissue components are classified: fibrous, fibro/fatty, necrotic core and calcium. Existing technology determines only the area of each component within the plaque. Quantitative, objective characterisation of other plaque components' patterns within the plaque is lacking. The aim of this study was to determine new compositional and structural indices which indicate spatial distribution, heterogeneity and dispersity of each VH-IVUS-derived component within the plaque area and also with respect to the plaque-lumen border. We developed an automated computational system in Java for the analysis of both single cross-sectional segments and the whole length of the examined plaque (volumetric analysis). The following parameters were computed: the number of different solid segments and the area of the largest solid segment of each component within the plaque, the per cent of the lumen border that is surrounded by each component, the number of different solid segments and the largest area of a solid segment of each component that adjoins the lumen border. Especially components' localisation in relation to the lumen border may significantly influence plaque vulnerability and plaque-stent interaction, which should be investigated in future clinical studies. PMID:22974224

  12. Can eccentric arterial plaques alone cause flow stagnation points and favour thrombus incorporation?

    PubMed Central

    Beneli, Cristina T; Barbosa, Priscila F; Floriano, Elaine M; Abreu, Mônica A; Ramalho, Fernando S; Júnior, Jorge Elias; Rossi, Marcos A; Ramos, Simone G

    2009-01-01

    We have used an experimental model of aorta stenosis, with a Plexiglas plug, simulating a stable atheromatous plaque that promotes local turbulence and thrombosis. With animal survival of more than 24 h, we followed the partial fibrinolysis of the thrombus as well as its posterior organization and incorporation to the arterial wall as a neointima for up to 30 days. The mushroom plug form permitted the development of recirculation and stasis areas around it, favouring this evolution. Despite noted limitations, this study demonstrates that thrombus incorporation can contribute to plaque extension, as it can promote recirculation and stasis areas. PMID:19563612

  13. Feature-based characterization of motion-contaminated calcified plaques in cardiac multidetector CT

    SciTech Connect

    King, Martin; Giger, Maryellen L.; Suzuki, Kenji; Pan, Xiaochuan [Department of Radiology, Committee on Medical Physics, University of Chicago, Chicago, Illinois 60637 (United States)

    2007-12-15

    In coronary calcium scoring, motion artifacts affecting calcified plaques are commonly characterized using descriptive terms, which incorporate an element of subjectivity in their interpretations. Quantitative indices may improve the objective characterization of these motion artifacts. In this paper, an automated method for generating 12 quantitative indices, i.e., features that characterize the motion artifacts affecting calcified plaques, is presented. This method consists of using the rapid phase-correlated region-of-interest (ROI) tracking algorithm for reconstructing ROI images of calcified plaques automatically from the projection data obtained during a cardiac scan, and applying methods for extracting features from these images. The 12 features include two dynamic, six morphological, and four intensity-based features. The two dynamic features are three-dimensional (3D) velocity and 3D acceleration. The six morphological features include edge-based volume, threshold-based volume, sphericity, irregularity, average margin gradient, and variance of margin gradient. The four intensity-based features are maximum intensity, mean intensity, minimum intensity, and standard deviation of intensity. The 12 features were extracted from 54 reconstructed sets of simulated four-dimensional images from the dynamic NCAT phantom involving six calcified plaques under nine heart rate/multi-sector gating combinations. In order to determine how well the 12 features correlated with a plaque motion index, which was derived from the trajectory of the plaque, partial correlation coefficients adjusted for heart rate, number of gated sectors, and mean feature values of the six plaques were calculated for all 12 features. Features exhibiting stronger correlations (|r| set-membership sign [0.60,1.00]) with the motion index were 3D velocity, maximum intensity, and standard deviation of intensity. Features demonstrating stronger correlations (|r| set-membership sign [0.60,1.00]) with other features mostly involved intensity-based features. Edge-based volume/irregularity and average margin gradient/variance of margin gradient were the only two feature pairs out of 12 with stronger correlations that did not involve intensity-based features. Automatically extracted features of the motion artifacts affecting calcified plaques in cardiac computed tomography images potentially can be used to develop models for predicting image assessability with respect to motion artifacts.

  14. The Therapeuatic Effect of Endostar on Soft Carotid Plaque Neovascularization in Patients with Non-small Cell Lung Cancer

    PubMed Central

    Pu, Zhaoxia; Wang, Yao; Zhang, Ying; Huang, Jing; Hong, Yurong; He, Huiliao; Liu, Chunmei; Chen, Shuyuan; Grayburn, Paul A.; Huang, Pintong

    2015-01-01

    The purpose of this study was to investigate the effect of the angiogenesis inhibitor Endostar on carotid plaque neovascularization in patients with non-small cell lung cancer (NSCLC) using contrast-enhanced ultrasound (CEUS). Ninety-one patients who had NSCLC with soft carotid plaques were selected for treatment either with the NP regimen (vinorelbine + cisplatin) (43 patients) or with the ENP regimen (Endostar + NP) (48 patients). Plaque thickness and neovascularization of the plaque were assessed before and at 1 month after treatment using CEUS. Enhanced intensity (EI) of CEUS was used for quantification of plaque neovascularization. There was no significant changes in any group in thickness of plaque between recruitment and 1 month after treatment (P > 0.05 for all). There was no significant change in the EI of plaque in the controls or NP groups at 1 month after treatment (P > 0.05), while EI in the ENP group was significantly reduced at 1 month after treatment (P < 0.01) and significantly lower than that in the controls or NP group at 1 month after treatment (P < 0.001 both). This study indicates that carotid soft plaque neovascularization in patients with NSCLC can be reduced by anti-angiogenesis treatment. PMID:25753083

  15. Regional Atherosclerotic Plaque Properties in ApoE–\\/– Mice Quantified by Atomic Force, Immunofluorescence, and Light Microscopy

    Microsoft Academic Search

    H. N. Hayenga; A. Trache; J. Trzeciakowski; J. D. Humphrey

    2011-01-01

    Elucidating regional material properties of arterial tissue is fundamental to predicting transmural stresses and understanding how tissue stiffness influences cellular responses and vice versa. Atomic force microscopy (AFM) was used to measure point-wise the axial compressive stiffness of healthy aortas and atherosclerotic plaques at micron level separation distances. Cross sections of plaques were obtained from a widely used animal model

  16. The Psoriasis Area and Severity Index Is the Adequate Criterion to Define Severity in Chronic Plaque-Type Psoriasis

    Microsoft Academic Search

    Jochen Schmitt; Gottfried Wozel

    2005-01-01

    Background: Chronic plaque-type psoriasis is a major dermatosis, but a significant question is still unanswered: What defines severity in chronic plaque-type psoriasis? While objective assessments like the Psoriasis Area and Severity Index (PASI) have frequently been used in clinical trials, quality of life (QOL) questionnaires are currently becoming more and more popular. Objective: This article summarizes the most important objective

  17. Galantamine Slows Down Plaque Formation and Behavioral Decline in the 5XFAD Mouse Model of Alzheimer’s Disease

    PubMed Central

    Bhattacharya, Soumee; Haertel, Christin; Maelicke, Alfred; Montag, Dirk

    2014-01-01

    The plant alkaloid galantamine is an established symptomatic drug treatment for Alzheimer’s disease (AD), providing temporary cognitive and global relief in human patients. In this study, the 5X Familial Alzheimer’s Disease (5XFAD) mouse model was used to investigate the effect of chronic galantamine treatment on behavior and amyloid ? (A?) plaque deposition in the mouse brain. Quantification of plaques in untreated 5XFAD mice showed a gender specific phenotype; the plaque density increased steadily reaching saturation in males after 10 months of age, whereas in females the density further increased until after 14 months of age. Moreover, females consistently displayed a higher plaque density in comparison to males of the same age. Chronic oral treatment with galantamine resulted in improved performance in behavioral tests, such as open field and light-dark avoidance, already at mildly affected stages compared to untreated controls. Treated animals of both sexes showed significantly lower plaque density in the brain, i.e., the entorhinal cortex and hippocampus, gliosis being always positively correlated to plaque load. A high dose treatment with a daily uptake of 26 mg/kg body weight was tolerated well and produced significantly larger positive effects than a lower dose treatment (14 mg/kg body weight) in terms of plaque density and behavior. These results strongly support that galantamine, in addition to improving cognitive and behavioral symptoms in AD, may have disease-modifying and neuroprotective properties, as is indicated by delayed A? plaque formation and reduced gliosis. PMID:24586789

  18. The Effect of Chlorhexidine and Zinc\\/Triclosan Mouthrinses on the Production of Acids in Dental Plaque

    Microsoft Academic Search

    J. S. van der Hoeven; D. Cummins; M. J. M. Schaeken; F. J. G. van der Ouderaa

    1993-01-01

    Chlorhexidine, and zinc in combination with triclosan, are used as anti-plaque agents in the prevention of gingivitis. The multifunctional activity of these compounds against bacterial cells has been proposed to include interference with sugar transport and reduction of glycolysis. In this study the ability of the agents to reduce acid production in dental plaque in vivo has been investigated. Samples

  19. [Enhanced formation of plaque in RNA phages/bacteria systems under the effect of surface-active preparations].

    PubMed

    Menzel, G

    1985-01-01

    The effect of 21 surfactants on the plaque formation was tested in three RNA-phages/Escherichia coli systems and in one RNA-phage/Pseudomonas aeruginosa system. Especially anionic detergents proved to be able to influence the plaque formation substantially. In high concentrations of Metaupon, Fekunil 602, Fekunil S-BA, Emulgator W 270, and Emulgator O-BA the plaque formation by the phages M 12 and f2 was inhibited and in low concentrations it was promoted. In the system Q beta/E. coli AB 301 the effect of the detergents mentioned was restricted to the prevention of the appearance of plaques. The detergent E 30 brought about only plaque inhibitions, too, in all used RNA-phages/E. coli systems. The treatment with effective detergents in the system PP7/P. aeruginosa, however, increased only the number of plaques. This phenomenon was evident in the formation of radiate plaque patterns in the lawn of bacteria. In the case of RNA-phages of E. coli the formation of such trains of lysis depends on the choice of the nutritive medium. The addition of the detergent Fekunil 602 at different times after the contact between phages and host bacteria affects the length of the beams of lysis. The ionogenity of surfactants seems to be of importance for the formation of radiate plaque patterns, since the tested cationic compound and the nonionic surfactants, contrary to anionic surfactants, did not cause any beams of lysis. PMID:3923185

  20. Southern Blot Analysis of Clonal Rearrangements of T-cell Receptor Gene in Plaque Lesion of Mycosis Fungoides

    Microsoft Academic Search

    Naoko Dosaka; Toshihiro Tanaka; Mayumi Fujita; Yoshiki Miyachi; Takeshi Horio; Sadao Imamura

    1989-01-01

    T-cell populations of 22 plaque lesions from seven mycosis fungoides patients were studied for clonal rearrangement of the ? chain of the T-cell receptor (T? gene. All plaque lesions employed in this study showed clinically similar appearance. Histologically, all the biopsy specimens showed epidermotropism and the dermal infiltration of mononuclear cells including atypical cells. Histochemically, the majority of the infiltrated

  1. The effect of iron in MRI and transverse relaxation of amyloid-beta plaques in Alzheimer's disease.

    PubMed

    Meadowcroft, Mark D; Peters, Douglas G; Dewal, Rahul P; Connor, James R; Yang, Qing X

    2015-03-01

    Dysregulation of neural iron is known to occur during the progression of Alzheimer's disease. The visualization of amyloid-beta (A?) plaques with MRI has largely been credited to rapid proton relaxation in the vicinity of plaques as a result of focal iron deposition. The goal of this work was to determine the relationship between local relaxation and related focal iron content associated with A? plaques. Alzheimer's disease (n=5) and control tissue (n=3) sample slices from the entorhinal cortex were treated overnight with the iron chelator deferoxamine or saline, and microscopic gradient-echo MRI datasets were taken. Subsequent to imaging, the same slices were stained for A? and iron, and then compared with regard to parametric R2 * relaxation maps and gradient-echo-weighted MR images. A? plaques in both chelated and unchelated tissue generated MR hypo-intensities and showed relaxation rates significantly greater than the surrounding tissue. The transverse relaxation rate associated with amyloid plaques was determined not to be solely a result of iron load, as much of the relaxation associated with A? plaques remained following iron chelation. The data indicate a dual relaxation mechanism associated with A? plaques, such that iron and plaque composition synergistically produce transverse relaxation. PMID:25530083

  2. Arsenic rich iron plaque on macrophyte roots an ecotoxicological risk? M.A. Taggart a,b,*, R. Mateo b

    E-print Network

    Green, Andy J.

    Arsenic rich iron plaque on macrophyte roots ­ an ecotoxicological risk? M.A. Taggart a,b,*, R transfer Wetlands Phytoremediation a b s t r a c t Arsenic is known to accumulate with iron plaque on macrophyte roots. Three to four years after the Aznalco´ llar mine spill (Spain), residual arsenic

  3. A?-Associated cerebral angiopathy and senile plaques with neurofibrillary tangles and cerebral hemorrhage in an aged wolverine ( Gulo gulo)

    Microsoft Academic Search

    Karen E. Roertgen; Joseph E. Parisi; H. Brent Clark; Donald L. Barnes; Timothy D. O'Brien; Kenneth H. Johnson

    1996-01-01

    In this study of an aged wolverine (Gulo gulo), we document neuropathologic lesions (cerebral amyloid angiopathy (CAA), neuritic plaques (NPs), neurofibrillary tangles (NFTs), and granulovacuolar degeneration strikingly similar to those present in aging and Alzheimer's disease (AD), with the additional finding of concurrent cerebral hemorrhage. A? immunoreactive cerebral amyloid angiopathy and senile plaques (neuritic and diffuse) were present throughout the

  4. Quantification of carotid plaque elasticity and intraplaque neovascularization using contrast-enhanced ultrasound and image registration-based elastography.

    PubMed

    Zhang, Qi; Li, Chaolun; Zhou, Moli; Liao, Yu; Huang, Chunchun; Shi, Jun; Wang, Yuanyuan; Wang, Wenping

    2015-09-01

    It is valuable for evaluation of carotid plaque vulnerability to investigate the relation between intraplaque neovascularization (IPN) and plaque elasticity. The contrast-enhanced ultrasound (CEUS) has been used in IPN measurement, but it cannot assess plaque elasticity. The aim of this study was to develop an ultrasound elastography technique based on registration of CEUS sequential images and to use this technique for direct comparison between IPN and plaque elasticity. We employed a nonrigid image registration method using the free-form deformation model to register a pair of clinical CEUS images at systole and diastole. The 2D displacement field of the plaque was estimated and then utilized to calculate the axial and lateral strain distributions within the plaque, from which quantitative strain parameters were obtained. The IPN was measured semiquantitatively with visual assessment and quantitatively with the time-intensity curve analysis and the analysis of contrast agent spatial distributions. Histopathology with CD34 staining for quantification of microvessel density (MVD) was performed on plaques excised by carotid endarterectomy. Simulation experiments showed that the mean absolute error and the root mean squared error of the displacement estimation were 0.325±0.180 pixel (7.2%±3.8%) and 0.556±0.284 pixel (12.3%±6.1%), respectively, demonstrating high accuracy of the elastography technique. Thirty-eight plaques in 29 patients met the inclusion criteria for the elastography and image analysis, where ten plaques underwent endarterectomy. The 95th percentile (A95) and standard deviation (Asd) of the axial strains exhibited significant differences between the low and high grades of IPN visually assessed (p<0.01). A95 (R=0.579; p<0.001) and Asd (R=0.609; p<0.001) were correlated with the enhanced intensity of plaque, and also correlated with the MVD (R=0.793 and 0.817, respectively; p<0.01), suggesting that plaque became softer and more elastically heterogeneous as IPN increased. These findings provide direct and quantitative evidence for the associations between plaque strains and IPN and might be helpful for evaluation of carotid plaque vulnerability and for plaque risk stratification. PMID:26074459

  5. Localization of Oxidized Low-Density Lipoprotein and Its Relation to Plaque Morphology in Human Coronary Artery

    PubMed Central

    Uchida, Yasumi; Maezawa, Yuko; Uchida, Yasuto; Hiruta, Nobuyuki; Shimoyama, Ei; Kawai, Seiji

    2013-01-01

    Objectives Oxidized low-density lipoprotein (oxLDL) plays a key role in the formation of atherosclerotic plaques. However, its localization in human coronary arterial wall is not well understood. The present study was performed to visualize deposition sites and patterns of native oxLDL and their relation to plaque morphology in human coronary artery. Methods Evans blue dye (EB) elicits a violet fluorescence by excitation at 345-nm and emission at 420-nm, and a reddish-brown fluorescence by excitation at 470-nm and emission at 515-nm characteristic of oxLDL only. Therefore, native oxLDL in excised human coronary artery were investigated by color fluorescent microscopy (CFM) using EB as a biomarker. Results (1) By luminal surface scan with CFM, the % incidence of oxLDL in 38 normal segments, 41 white plaques and 32 yellow plaques that were classified by conventional angioscopy, was respectively 26, 44 and 94, indicating significantly (p<0.05) higher incidence in the latter than the former two groups. Distribution pattern was classified as patchy, diffuse and web-like. Web-like pattern was observed only in yellow plaques with necrotic core. (2) By transected surface scan, oxLDL deposited within superficial layer in normal segments and diffusely within both superficial and deep layers in white and yellow plaques. In yellow plaques with necrotic core, oxLDL deposited not only in the marginal zone of the necrotic core but also in the fibrous cap. Conclusion Taken into consideration of the well-known process of coronary plaque growth, the results suggest that oxLDL begins to deposit in human coronary artery wall before plaque formation and increasingly deposits with plaque growth, exhibiting different deposition sites and patterns depending on morphological changes. PMID:23393566

  6. Local Non-Esterified Fatty Acids Correlate With Inflammation in Atheroma Plaques of Patients With Type 2 Diabetes

    PubMed Central

    Mas, Sebastián; Martínez-Pinna, Roxana; Martín-Ventura, Jose Luis; Pérez, Raul; Gomez-Garre, Dulcenombre; Ortiz, Alberto; Fernandez-Cruz, Arturo; Vivanco, Fernando; Egido, Jesús

    2010-01-01

    OBJECTIVE Atherosclerosis is prevalent in diabetic patients, but there is little information on the localization of nonesterified fatty acids (NEFAs) within the plaque and their relationship with inflammation. We sought to characterize the NEFA composition and location in human diabetic atheroma plaques by metabolomic analysis and imaging and to address their relationship with inflammation activity. RESEARCH DESIGN AND METHODS Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used for metabolomic analysis imaging of frozen carotid atheroma plaques. Carotid endarterectomy specimens were used for conventional immunohistochemistry, laser-capture microdissection quantitative PCR, and in situ Southwestern hybridization. Biological actions of linoleic acid were studied in cultured vascular smooth muscle cells (VSMCs). RESULTS TOF-SIMS imaging evidenced a significant increase in the quantity of several NEFA in diabetic versus nondiabetic atheroma plaques. Higher levels of NEFA were also found in diabetic sera. The presence of LPL mRNA in NEFA-rich areas of the atheroma plaque, as well as the lack of correlation between serum and plaque NEFA, suggests a local origin for plaque NEFA. The pattern of distribution of plaque NEFA is similar to that of MCP-1, LPL, and activated NF-?B. Diabetic endarterectomy specimens showed higher numbers of infiltrating macrophages and T-lymphocytes—a finding that associated with higher NEFA levels. Finally, linoleic acid activates NF-?B and upregulates NF-?B–mediated LPL and MCP-1 expression in cultured VSMC. DISCUSSION There is an increased presence of NEFA in diabetic plaque neointima. NEFA levels are higher in diabetic atheroma plaques than in nondiabetic subjects. We hypothesize that NEFA may be produced locally and contribute to local inflammation. PMID:20200316

  7. Epigenome-Guided Analysis of the Transcriptome of Plaque Macrophages during Atherosclerosis Regression Reveals Activation of the Wnt Signaling Pathway

    PubMed Central

    Menon, Prashanthi; Podolsky, Irina; Feig, Jonathan E.; Aderem, Alan; Fisher, Edward A.; Gold, Elizabeth S.

    2014-01-01

    We report the first systems biology investigation of regulators controlling arterial plaque macrophage transcriptional changes in response to lipid lowering in vivo in two distinct mouse models of atherosclerosis regression. Transcriptome measurements from plaque macrophages from the Reversa mouse were integrated with measurements from an aortic transplant-based mouse model of plaque regression. Functional relevance of the genes detected as differentially expressed in plaque macrophages in response to lipid lowering in vivo was assessed through analysis of gene functional annotations, overlap with in vitro foam cell studies, and overlap of associated eQTLs with human atherosclerosis/CAD risk SNPs. To identify transcription factors that control plaque macrophage responses to lipid lowering in vivo, we used an integrative strategy – leveraging macrophage epigenomic measurements – to detect enrichment of transcription factor binding sites upstream of genes that are differentially expressed in plaque macrophages during regression. The integrated analysis uncovered eight transcription factor binding site elements that were statistically overrepresented within the 5? regulatory regions of genes that were upregulated in plaque macrophages in the Reversa model under maximal regression conditions and within the 5? regulatory regions of genes that were upregulated in the aortic transplant model during regression. Of these, the TCF/LEF binding site was present in promoters of upregulated genes related to cell motility, suggesting that the canonical Wnt signaling pathway may be activated in plaque macrophages during regression. We validated this network-based prediction by demonstrating that ?-catenin expression is higher in regressing (vs. control group) plaques in both regression models, and we further demonstrated that stimulation of canonical Wnt signaling increases macrophage migration in vitro. These results suggest involvement of canonical Wnt signaling in macrophage emigration from the plaque during lipid lowering-induced regression, and they illustrate the discovery potential of an epigenome-guided, systems approach to understanding atherosclerosis regression. PMID:25474352

  8. Darkfield microscopy of subgingival plaque of an urban black population with poor oral hygiene.

    PubMed

    Reddy, J; Africa, C W; Parker, J R

    1986-07-01

    A low socio-economic community residing in Crossroads, Cape Town, consists of people who originated from the Eastern Cape areas of the Ciskei and Transkei. These individuals have had virtually no dental care, with the exception of emergency treatment for pain. A darkfield microscopic study of a random sample of 52 individuals was undertaken to determine the predominant morphological forms in the subgingival plaque of this population. Spirochetes were found to constitute 42.1% and motile rods, 7.7%, of the total darkfield microscopic count. Clinical assessment of the periodontal status of 100 individuals revealed the following mean values; plaque index (PI) = 1.44, gingival index (GI) = 1.31, probing depth (PD) = 2.35 mm and loss of attachment = 0.64 mm. Subgingival calculus deposits were present in 42% of the group and little or no mobility of the teeth was evident. Poor oral hygiene resulted in 90% of the tooth surfaces of the sampled population in Crossroads being covered with plaque, yet these individuals appear to be resistant to periodontitis. The high proportions of spirochetes and motile rods found in the subgingival plaque of this group were not indicative of periodontitis and therefore, fail to confirm the findings of other investigators. PMID:3462205

  9. Quantitative Analysis of Circumferential Plaque Distribution in Human Coronary Arteries in

    E-print Network

    Wahle, Andreas

    /adventitia contours are segmented semi-automatically from the IVUS data, as acquired with end-diastolic gating of constant curvature indicate lower wall shear stress on the inner curvature (Figure 2). · Given that low wall shear stress is associated with plaque development, can a direct relation between local curvature

  10. Salivary alpha-amylase: role in dental plaque and caries formation.

    PubMed

    Scannapieco, F A; Torres, G; Levine, M J

    1993-01-01

    Salivary alpha-amylase, one of the most plentiful components in human saliva, has at least three distinct biological functions. The enzymatic activity of alpha-amylase undoubtedly plays a role in carbohydrate digestion. Amylase in solution binds with high affinity to a selected group of oral streptococci, a function that may contribute to bacterial clearance and nutrition. The fact that alpha-amylase is also found in acquired enamel pellicle suggests a role in the adhesion of alpha-amylase-binding bacteria. All of these biological activities seem to depend on an intact enzyme conformation. Binding of alpha-amylase to bacteria and teeth may have important implications for dental plaque and caries formation. alpha-Amylase bound to bacteria in plaque may facilitate dietary starch hydrolysis to provide additional glucose for metabolism by plaque microorganisms in close proximity to the tooth surface. The resulting lactic acid produced may be added to the pool of acid in plaque to contribute to tooth demineralization. PMID:8373987

  11. Clinically stable angina pectoris is not necessarily associated with histologically stable atherosclerotic plaques

    Microsoft Academic Search

    A. C. van der Wal; A. E. Becker; K. T. Koch; J. J. Piek; P. Teeling; C. M. van der Loos; G. K. David

    1996-01-01

    OBJECTIVE: To investigate the extent of plaque inflammation in culprit lesions of patients with chronic stable angina. DESIGN: Retrospective study. SETTING: Amsterdam reference centre. SUBJECTS: 89 consecutive patients who underwent directional coronary atherectomy, 58 of whom met the following inclusion criteria: chronic stable angina (Canadian Cardiovascular Society classification 1-3 (group 1, n = 28)); unstable angina (Braunwald class II (group

  12. The effect of chewing xylitol gum on the plaque and saliva levels of Streptococcus mutans.

    PubMed

    Loesche, W J; Grossman, N S; Earnest, R; Corpron, R

    1984-04-01

    Eating foods containing sucrose between meals can be highly cariogenic. The use of sucrose substitutes that provide the hedonistic appeal of sucrose, yet are not fermented by the plaque flora to the low pHs that are associated with caries, is a reasonable approach to caries control. Xylitol, a sweet-tasting pentitol, has been reported to cause about an 80% reduction in caries increment when chewed in a gum. The present investigation was designed to determine whether the chewing of xylitol gums affected the salivary and plaque levels of S mutans and lactobacilli. The chewing of xylitol gums for four weeks caused a significant reduction in saliva levels and plaque proportions of S mutans compared with pretreatment values. The levels were also significantly reduced to values obtained by chewing either sorbitol or fructose sweetened gum. The chewing of various gums had no significant effect on the proportions of lactobacilli in the plaque. These findings suggested that the small amounts of xylitol used (about 5 gm) resulted in a suppression of S mutans. PMID:6427315

  13. Flourescence analysis of ALA-induced Protoporphyrin IX in psoriatic plaque

    NASA Astrophysics Data System (ADS)

    Stringer, Mark R.; Robinson, Dominic J.; Collins, P.

    1996-01-01

    The success reported for the treatment of superficial skin carcinomas by photodynamic therapy (PDT), following topical application of 5-aminolaevulinic acid (ALA), has therapeutic implications for the treatment of other skin disorders. This presentation describes the accumulation of the photosensitizing agent protoporphyrin IX (PpIX) in areas of psoriatic plaque, by monitoring the fluorescence emission induced by low-intensity laser excitation at 488 nm. We present the results from 15 patients, with a total of 42 plaques. These results show that PpIX fluorescence increases in intensity within the 6 hour period following application of ALA, which implies there is a potential for PDT. The emission is localized to the area of ALA application and the effect of occlusion appears insignificant. Also, the rate of increase, and maximum intensity of fluorescence emission, is not directly related to the applied quantity of ALA. The variability of the fluorescence intensity is as great between plaques at different sites on the same patient as between different patients. We also present measurements of the depletion in intensity of fluorescence emission during PDT treatment, using white light, at an irradiance of 25 mW cm-2, that is a consequence of the molecular photo-oxidation of PpIX. The use of fluorescence measurements in predicting the therapeutic effect of treating plaque psoriasis by ALA-PDT is discussed.

  14. Toll-Like Receptor 4 Immunohistochemical Expression Is Enhanced in Macrophages of Symptomatic Carotid Atherosclerotic Plaques

    Microsoft Academic Search

    Athanasios Katsargyris; Sotirios Tsiodras; Stamatios Theocharis; Konstantinos Giaginis; Ioanna Vasileiou; Christos Bakoyiannis; Sotiris Georgopoulos; Elias Bastounis; Chris Klonaris

    2011-01-01

    Background: A growing body of evidence supports a role for Toll-like receptor 4 (TLR4), a primary receptor of the innate immune system, in atherosclerosis initiation and progression. Carotid atheroma macrophages (MACs) and smooth muscle cells (SMCs) express TLR4; nevertheless, correlations with epidemiological and clinical variables and especially cerebrovascular symptomatology remain unsettled. Methods: Carotid atherosclerotic plaques were obtained by standard carotid

  15. Myeloid I?B? deficiency promotes atherogenesis by enhancing leukocyte recruitment to the plaques.

    PubMed

    Goossens, Pieter; Vergouwe, Monique N; Gijbels, Marion J J; Curfs, Danielle M J; van Woezik, Johannes H G; Hoeksema, Marten A; Xanthoulea, Sofia; Leenen, Pieter J M; Rupec, Rudolf A; Hofker, Marten H; de Winther, Menno P J

    2011-01-01

    Activation of the transcription factor NF-?B appears to be involved in different stages of atherogenesis. In this paper we investigate the role of NF-?B inhibitor I?B? in atherosclerosis. Myeloid-specific deletion of I?B? results in larger and more advanced lesions in LDL-R-deficient mice without affecting the compositional phenotype of the plaques or systemic inflammatory markers in the plasma. We show that I?B?-deleted macrophages display enhanced adhesion to an in vitro endothelial cell layer, coinciding with an increased expression of the chemokine CCL5. Also, in vivo we found that I?B?(del) mice had more leukocytes adhering to the luminal side of the endothelial cell layers that cover the atherosclerotic plaques. Moreover, we introduce ER-MP58 in this paper as a new immunohistochemical tool for quantifying newly recruited myeloid cells in the atherosclerotic lesion. This staining confirms that in I?B?(del) mice more leukocytes are attracted to the plaques. In conclusion, we show that I?B? deletion in myeloid cells promotes atherogenesis, probably through an induced leukocyte recruitment to plaques. PMID:21814576

  16. Myeloid I?B? Deficiency Promotes Atherogenesis by Enhancing Leukocyte Recruitment to the Plaques

    PubMed Central

    Goossens, Pieter; Vergouwe, Monique N.; Gijbels, Marion J. J.; Curfs, Danielle M. J.; van Woezik, Johannes H. G.; Hoeksema, Marten A.; Xanthoulea, Sofia; Leenen, Pieter J. M.; Rupec, Rudolf A.; Hofker, Marten H.; de Winther, Menno P. J.

    2011-01-01

    Activation of the transcription factor NF-?B appears to be involved in different stages of atherogenesis. In this paper we investigate the role of NF-?B inhibitor I?B? in atherosclerosis. Myeloid-specific deletion of I?B? results in larger and more advanced lesions in LDL-R-deficient mice without affecting the compositional phenotype of the plaques or systemic inflammatory markers in the plasma. We show that I?B?-deleted macrophages display enhanced adhesion to an in vitro endothelial cell layer, coinciding with an increased expression of the chemokine CCL5. Also, in vivo we found that I?B?del mice had more leukocytes adhering to the luminal side of the endothelial cell layers that cover the atherosclerotic plaques. Moreover, we introduce ER-MP58 in this paper as a new immunohistochemical tool for quantifying newly recruited myeloid cells in the atherosclerotic lesion. This staining confirms that in I?B?del mice more leukocytes are attracted to the plaques. In conclusion, we show that I?B? deletion in myeloid cells promotes atherogenesis, probably through an induced leukocyte recruitment to plaques. PMID:21814576

  17. FACTORS AFFECTING IRON SULFIDE-ENHANCED BACTERIOPHAGE PLAQUE ASSAYS IN SALMONELLA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Formation of iron sulfide from reaction of ferric ions in bacteriological media with hydrogen sulfide (H2S) produced by bacteria has been exploited to enhance contrast of bacteriophage plaques in sulfate-reducing strains of Salmonella. Ferric ammonium citrate (FAC) and sodium thiosulfate (ST) added ...

  18. Plaque characterization in ex vivo MRI evaluated by dense 3D correspondence with histology

    NASA Astrophysics Data System (ADS)

    van Engelen, Arna; de Bruijne, Marleen; Klein, Stefan; Verhagen, Hence; Groen, Harald; Wentzel, Jolanda; van der Lugt, Aad; Niessen, Wiro

    2011-03-01

    Automatic quantification of carotid artery plaque composition is important in the development of methods that distinguish vulnerable from stable plaques. MRI has shown to be capable of imaging different components noninvasively. We present a new plaque classification method which uses 3D registration of histology data with ex vivo MRI data, using non-rigid registration, both for training and evaluation. This is more objective than previously presented methods, as it eliminates selection bias that is introduced when 2D MRI slices are manually matched to histological slices before evaluation. Histological slices of human atherosclerotic plaques were manually segmented into necrotic core, fibrous tissue and calcification. Classification of these three components was voxelwise evaluated. As features the intensity, gradient magnitude and Laplacian in four MRI sequences after different degrees of Gaussian smoothing, and the distances to the lumen and the outer vessel wall, were used. Performance of linear and quadratic discriminant classifiers for different combinations of features was evaluated. Best accuracy (72.5 +/- 7.7%) was reached with the linear classifier when all features were used. Although this was only a minor improvement to the accuracy of a classifier that only included the intensities and distance features (71.6 +/- 7.9%), the difference was statistically significant (paired t-test, p<0.05). Good sensitivity and specificity for calcification was reached (83% and 95% respectively), however, differentiation between fibrous (sensitivity 85%, specificity 60%) and necrotic tissue (sensitivity 49%, specificity 89%) was more difficult.

  19. Evaluation of dental plaque control in patients wearing fixed orthodontic appliances: a clinical study.

    PubMed

    Ousehal, Lahcen; Lazrak, Laila; Es-Said, Rabia; Hamdoune, Hind; Elquars, Farid; Khadija, Amine

    2011-03-01

    Multibracket orthodontic appliances increase dental plaque retention and make teethbrushing more difficult for patients. As a result, advice from the orthodontist on oral hygiene along with patient motivation regarding teethbrushing are particularly important. The aim of this study was to compare the efficacy of electric toothbrushes with that of manual brushing associated with mouth-rinses comprising chlorhexidine (0.12%) and 0% alcohol. To this end, 84 patients receiving current orthodontic treatment were randomly selected from patients treated at the Dento-Facial Orthopedics department in the Casablanca Dental Consultation and Treatment Center. Selected patients were divided into three groups: Group 1: manual teethbrushing; Group 2: electric teethbrushing; Group 3: manual brushing combined with mouth rinse. Oral hygiene was assessed using the Loe-Silness plaque and gingival indices. Measurements were made before and 4 weeks after the observation period. Results were subjected to statistical comparison in order to determine the group showing greatest improvement and to deduce the best means of controlling bacterial plaque. The electric toothbrush and the chlorhexidine mouth rinse appear to control dental plaque more effectively than manual teethbrushing alone. Following this study, patients receiving multibracket treatment were invited to combine manual brushing with short clinical mouth-rinsing sessions or to use an electric toothbrush. PMID:21277846

  20. Supplementary taurine may stabilize atheromatous plaque by antagonizing the activation of metalloproteinases by hypochlorous acid

    Microsoft Academic Search

    Mark F McCarty

    2004-01-01

    The rupture of atherosclerotic plaque, responsible for triggering the majority of myocardial infarctions, presumably requires proteolysis of collagen fibers and other protein components of the intercellular matrix. This is achieved by activated matrix metalloproteases (MMPs) secreted by intimal macrophages and foam cells. MMPs are synthesized as inactive pro-enzymes in which coordinate binding of the thiol group of a key cysteine

  1. Computational approaches for analyzing the mechanics of atherosclerotic plaques: a review.

    PubMed

    Holzapfel, Gerhard A; Mulvihill, John J; Cunnane, Eoghan M; Walsh, Michael T

    2014-03-01

    Vulnerable and stable atherosclerotic plaques are heterogeneous living materials with peculiar mechanical behaviors depending on geometry, composition, loading and boundary conditions. Computational approaches have the potential to characterize the three-dimensional stress/strain distributions in patient-specific diseased arteries of different types and sclerotic morphologies and to estimate the risk of plaque rupture which is the main trigger of acute cardiovascular events. This review article attempts to summarize a few finite element (FE) studies for different vessel types, and how these studies were performed focusing on the used stress measure, inclusion of residual stress, used imaging modality and material model. In addition to histology the most used imaging modalities are described, the most common nonlinear material models and the limited number of models for plaque rupture used for such studies are provided in more detail. A critical discussion on stress measures and threshold stress values for plaque rupture used within the FE studies emphasizes the need to develop a more location and tissue-specific threshold value, and a more appropriate failure criterion. With this addition future FE studies should also consider more advanced strain-energy functions which then fit better to location and tissue-specific experimental data. PMID:24491496

  2. Mathematical modelling of atheroma plaque formation and development in coronary arteries

    PubMed Central

    Cilla, Myriam; Peña, Estefanía; Martínez, Miguel A.

    2014-01-01

    Atherosclerosis is a vascular disease caused by inflammation of the arterial wall, which results in the accumulation of low-density lipoprotein (LDL) cholesterol, monocytes, macrophages and fat-laden foam cells at the place of the inflammation. This process is commonly referred to as plaque formation. The evolution of the atherosclerosis disease, and in particular the influence of wall shear stress on the growth of atherosclerotic plaques, is still a poorly understood phenomenon. This work presents a mathematical model to reproduce atheroma plaque growth in coronary arteries. This model uses the Navier–Stokes equations and Darcy's law for fluid dynamics, convection–diffusion–reaction equations for modelling the mass balance in the lumen and intima, and the Kedem–Katchalsky equations for the interfacial coupling at membranes, i.e. endothelium. The volume flux and the solute flux across the interface between the fluid and the porous domains are governed by a three-pore model. The main species and substances which play a role in early atherosclerosis development have been considered in the model, i.e. LDL, oxidized LDL, monocytes, macrophages, foam cells, smooth muscle cells, cytokines and collagen. Furthermore, experimental data taken from the literature have been used in order to physiologically determine model parameters. The mathematical model has been implemented in a representative axisymmetric geometrical coronary artery model. The results show that the mathematical model is able to qualitatively capture the atheroma plaque development observed in the intima layer. PMID:24196695

  3. Positron emission tomography of the vulnerable atherosclerotic plaque in man – a contemporary review

    PubMed Central

    Pedersen, Sune F; Hag, Anne Mette F; Klausen, Thomas L; Ripa, Rasmus S; Bodholdt, Rasmus P; Kjær, Andreas

    2014-01-01

    Atherosclerosis is the primary underlying cause of cardiovascular disease (CVD). It is the leading cause of morbidity and mortality in the Western world today and is set to become the prevailing disease and major cause of death worldwide by 2020. In the 1950s surgical intervention was introduced to treat symptomatic patients with high-grade carotid artery stenosis due to atherosclerosis – a procedure known as carotid endarterectomy (CEA). By removing the atherosclerotic plaque from the affected carotid artery of these patients, CEA is beneficial by preventing subsequent ipsilateral ischemic stroke. However, it is known that patients with low to intermediate artery stenosis may still experience ischemic events, leading clinicians to consider plaque composition as an important feature of atherosclerosis. Today molecular imaging can be used for characterization, visualization and quantification of cellular and subcellular physiological processes as they take place in vivo; using this technology we can obtain valuable information on atherosclerostic plaque composition. Applying molecular imaging clinically to atherosclerotic disease therefore has the potential to identify atherosclerotic plaques vulnerable to rupture. This could prove to be an important tool for the selection of patients for CEA surgery in a health system increasingly focused on individualized treatment. This review focuses on current advances and future developments of in vivo atherosclerosis PET imaging in man. PMID:24289282

  4. Plaque Radiotherapy for Juxtapapillary Choroidal Melanoma Overhanging the Optic Disc in 141 Consecutive Patients

    Microsoft Academic Search

    Mandeep S. Sagoo; Carol L. Shields; Arman Mashayekhi; Jorge Freire; Jacqueline Emrich; Jay Reiff; Lydia Komarnicky; Jerry A. Shields

    2008-01-01

    Objective: To evaluate tumor control with plaque ra- diotherapy for juxtapapillary choroidal melanoma that overhangs the optic disc. Methods: Retrospective medical record review of 141 consecutivepatientswithdataoncomplicationsoftreat- ment, final visual acuity, visual loss, enucleation, tumor recurrence, metastasis, and death. Results: The median patient age was 61 years. Present- ing symptoms included reduced visual acuity in 72 eyes (51%), photopsia in 14

  5. Histological Stratification of Thick and Thin Plaque Psoriasis Explores Molecular Phenotypes with Clinical Implications

    PubMed Central

    Kim, Dong Joo; Brodmerkel, Carrie; Correa da Rosa, Joel; Krueger, James G.; Suárez-Fariñas, Mayte

    2015-01-01

    Psoriasis, which presents as red, scaly patches on the body, is a common, autoimmune skin disease that affects 2 to 3 percent of the world population. To leverage recent molecular findings into the personalized treatment of psoriasis, we need a strategy that integrates clinical stratification with molecular phenotyping. In this study, we sought to stratify psoriasis patients by histological measurements of epidermal thickness, and to compare their molecular characterizations by gene expression, serum cytokines, and response to biologics. We obtained histological measures of epidermal thickness in a cohort of 609 psoriasis patients, and identified a mixture of two subpopulations—thick and thin plaque psoriasis—from which they were derived. This stratification was verified in a subcohort of 65 patients from a previously published study with significant differences in inflammatory cell infiltrates in the psoriatic skin. Thick and thin plaque psoriasis shared 84.8% of the meta-analysis-derived psoriasis transcriptome, but a stronger dysregulation of the meta-analysis-derived psoriasis transcriptome was seen in thick plaque psoriasis on microarray. RT-PCR revealed that gene expression in thick and thin plaque psoriasis was different not only within psoriatic lesional skin but also in peripheral non-lesional skin. Additionally, differences in circulating cytokines and their changes in response to biologic treatments were found between the two subgroups. All together, we were able to integrate histological stratification with molecular phenotyping as a way of exploring clinical phenotypes with different expression levels of the psoriasis transcriptome and circulating cytokines. PMID:26176783

  6. Egg yolk consumption and carotid plaque J. David Spence a,*, David J.A. Jenkins b

    E-print Network

    Kite, Edwin

    Egg yolk consumption and carotid plaque J. David Spence a,*, David J.A. Jenkins b , Jean Davignon c Dietary cholesterol Egg yolk a b s t r a c t Background: Increasingly the potential harm from high cholesterol intake, and specifically from egg yolks, is considered insignificant. We therefore assessed total

  7. The neuroimmune guidance cue netrin-1 promotes atherosclerosis by inhibiting the emigration of macrophages from plaques

    Microsoft Academic Search

    Janine M van Gils; Merran C Derby; Luciana R Fernandes; Bhama Ramkhelawon; Tathagat D Ray; Katey J Rayner; Sajesh Parathath; Emilie Distel; Jessica L Feig; Jacqueline I Alvarez-Leite; Alistair J Rayner; Thomas O McDonald; Kevin D O'Brien; Lynda M Stuart; Edward A Fisher; Adam Lacy-Hulbert; Kathryn J Moore

    2012-01-01

    Atherosclerotic plaque formation is fueled by the persistence of lipid-laden macrophages in the artery wall. The mechanisms by which these cells become trapped, thereby establishing chronic inflammation, remain unknown. Here we found that netrin-1, a neuroimmune guidance cue, was secreted by macrophages in human and mouse atheroma, where it inactivated the migration of macrophages toward chemokines linked to their egress

  8. Segmentation of wall and plaque in in vitro vascular MR images.

    PubMed

    Yang, Fuxing; Holzapfel, Gerhard; Schulze-Bauer, Christian; Stollberger, Rudolf; Thedens, Daniel; Bolinger, Lizann; Stolpen, Alan; Sonka, Milan

    2003-10-01

    Atherosclerosis leads to heart attack and stroke, which are major killers in the western world. These cardiovascular events frequently result from local rupture of vulnerable atherosclerotic plaque. Non-invasive assessment of plaque vulnerability would dramatically change the way in which atherosclerotic disease is diagnosed, monitored, and treated. In this paper, we report a computerized method for segmentation of arterial wall layers and plaque from high-resolution volumetric MR images. The method uses dynamic programming to detect optimal borders in each MRI frame. The accuracy of the results was tested in 62 T1-weighted MR images from six vessel specimens in comparison to borders manually determined by an expert observer. The mean signed border positioning errors for the lumen, internal elastic lamina, and external elastic lamina borders were -0.1 +/- 0.1, 0.0 +/- 0.1, and -0.1 +/- 0.1 mm, respectively. The presented wall layer segmentation approach is one of the first steps towards non-invasive assessment of plaque vulnerability in atherosclerotic subjects. PMID:14609192

  9. Coal Tar 2% Foam in Combination with a Superpotent Corticosteroid Foam for Plaque Psoriasis

    PubMed Central

    Frankel, Amylynne J.; Del Rosso, James Q.

    2010-01-01

    Psoriasis is a chronic, inflammatory, immune-mediated, multi-system disease that is treated with a variety of medicines, including topical corticosteroids and, historically, coal tar. In this case, the authors evaluated whether combination therapy with coal tar foam 2% and a topical corticosteroid would induce a remission and maintain clearance of plaque-type psoriasis over an eight-week period. A 59-year-old Caucasian woman with plaque psoriasis of her elbows presented to the authors' dermatology clinic and was treated with clobetasol propionate 0.05% emollient foam in combination with coal tar 2% foam twice daily to her elbows for two weeks. After two weeks, the patient was switched to a maintenance regimen of twice-daily coal tar 2% foam during the week and twice-daily application of the corticosteroid on the weekends. The patient exhibited very favorable clearance of her plaque psoriasis on this regimen at her eight-week follow-up visit. In this case, the combination of coal tar 2% foam and clobetasol propionate 0.05% emollient foam twice daily was used effectively to induce remission of localized plaque psoriasis followed by an efficacious maintenance regimen, which incorporated intermittent therapy with both topical agents. PMID:20967195

  10. Quercetin intake with exercise modulates lipoprotein metabolism and reduces atherosclerosis plaque formation

    PubMed Central

    2014-01-01

    Study objectives We proposed that mice supplemented with quercetin, a class of flavonoids known to have antioxidant and anti-inflammatory properties, will have profound effects on the pathophysiology of atherosclerosis when combined with exercise. Study design Forty C57BL6 LDLr ?/? mice were divided into four groups (n?=?10): control untreated (NN); control group supplemented with 100 ?g/day of quercetin (NQ); exercise group (EN); and exercise group supplemented with 100 ?g/day of quercetin (EQ). All animals were fed atherogenic diet. The exercise groups were run on a treadmill for 30 minutes, 15 m/min for 5 days/week for 30 days. After 30 day animals were sacrificed and tissues were harvested. Results and conclusion Mice supplemented with quercetin during exercise sessions had 78% atherosclerotic plaque reduction compared to control mice and 40% less atherosclerotic plaque formation compared to control group supplemented with quercetin. The manifestation of the combination of quercetin supplementation with exercise was more evident in the pro-reverse cholesterol transport genes, indicating a plausible mechanism for their combined beneficial effect. The pathogenesis of atherosclerosis, the major cause of cardiovascular diseases (CVD), is multifactorial and therefore its treatment approaches and the ability to regress the plaque are complicated. Data from research on animal models and clinical studies have indicated that moderate daily exercise can alleviate the risk for the development of atherosclerotic plaques, while the same has not been true for the supplementation of antioxidants. PMID:24890098

  11. Mass Transport of Macromolecules within an In Vitro Model of Supragingival Plaque

    Microsoft Academic Search

    Thomas Thurnheer; Rudolf Gmur; Stuart Shapiro; Bernhard Guggenheim

    2003-01-01

    The aim of this study was to examine the diffusion of macromolecules through an in vitro biofilm model of supragingival plaque. Polyspecies biofilms containing Actinomyces naeslundii, Fusobacterium nucleatum, Strep- tococcus oralis, Streptococcus sobrinus, Veillonella dispar, and Candida albicans were formed on sintered hydroxy- apatite disks and then incubated at room temperature for defined periods with fluorescent markers with molecular weights

  12. A comparative study of O'nyong nyong virus with Chikungunya virus and plaque variants

    Microsoft Academic Search

    A. C. Chanas; Z. Hubalek; B. K. Johnson; D. I. H. Simpson

    1979-01-01

    Summary Two plaque variants of Chikungunya (CHIK) virus were serologically compared with O'nyong nyong (ONN) virus in order to elucidate the reported one way antigenic relationships between the two viruses. Three different hypotheses are examined and evidence is shown to support one of them.

  13. Aminonaphthalene 2Cyanoacrylate (ANCA) Probes Fluorescently Discriminate between Amyloid and Prion Plaques in Brain

    E-print Network

    Theodorakis, Emmanuel

    and Prion Plaques in Brain Kevin Cao, Mona Farahi, Marianna Dakanali, Willy M. Chang, Christina J. Sigurdson- (A) peptides associated with AD or from prion (PrPSc ) proteins associated with prion disease (Figure) PrPSc deposits in the corpus callosum of a prion-infected mouse. (C) Ex vivo fluorescence spectra

  14. SU-E-P-08: Alarming Range of Seed Activities Ordered for I-125 Plaque Brachytherapy

    SciTech Connect

    Merz, B [Oregon Health and Science University, Portland, OR (United States)

    2014-06-01

    Purpose: To investigate the variation in I-125 seed activities ordered by various clinics for their plaque brachytherapy cases under a standardized set of assumptions. Methods: A majority of the plaque programs in North America were contacted and a survey was designed to give a few standardized cases to allow inter-comparison of seed activities ordered. Tumor dose, treatment duration, number of seeds, plaque, and tumor apex were held constant in order to reveal differences in prescription point, seed type, and seed activity. Results: While the survey is presently underway, preliminary results show alarmingly wide variations between centers. Differences up to 45% have been found with 15% differences being common. Conclusion: Though knowledge of the TG-43 dose calculation formalism is common, a number of factors in the field of plaque brachytherapy lead to alarming differences in activity of I-125 seeds being ordered for a given tumor. Knowledge of the present reality of widely varying treatment activities, and thus doses to tumor and normal structures, should serve as motivation for centers involved in this modality to review their programs with others in the community and share their experiences.

  15. Chronic ?-secretase inhibition reduces amyloid plaque-associated instability of pre- and postsynaptic structures

    PubMed Central

    Liebscher, S; Page, R M; Käfer, K; Winkler, E; Quinn, K; Goldbach, E; Brigham, E F; Quincy, D; Basi, G S; Schenk, D B; Steiner, H; Bonhoeffer, T; Haass, C; Meyer-Luehmann, M; Hübener, M

    2014-01-01

    The loss of synapses is a strong histological correlate of the cognitive decline in Alzheimer's disease (AD). Amyloid ??peptide (A?), a cleavage product of the amyloid precursor protein (APP), exerts detrimental effects on synapses, a process thought to be causally related to the cognitive deficits in AD. Here, we used in vivo two-photon microscopy to characterize the dynamics of axonal boutons and dendritic spines in APP/Presenilin 1 (APPswe/PS1L166P)–green fluorescent protein (GFP) transgenic mice. Time-lapse imaging over 4 weeks revealed a pronounced, concerted instability of pre- and postsynaptic structures within the vicinity of amyloid plaques. Treatment with a novel sulfonamide-type ?-secretase inhibitor (GSI) attenuated the formation and growth of new plaques and, most importantly, led to a normalization of the enhanced dynamics of synaptic structures close to plaques. GSI treatment did neither affect spines and boutons distant from plaques in amyloid precursor protein/presenilin 1-GFP (APPPS1-GFP) nor those in GFP-control mice, suggesting no obvious neuropathological side effects of the drug. PMID:24061497

  16. Carotid plaque elasticity estimation using ultrasound elastography, MRI, and inverse FEA - A numerical feasibility study.

    PubMed

    Nieuwstadt, H A; Fekkes, S; Hansen, H H G; de Korte, C L; van der Lugt, A; Wentzel, J J; van der Steen, A F W; Gijsen, F J H

    2015-08-01

    The material properties of atherosclerotic plaques govern the biomechanical environment, which is associated with rupture-risk. We investigated the feasibility of noninvasively estimating carotid plaque component material properties through simulating ultrasound (US) elastography and in vivo magnetic resonance imaging (MRI), and solving the inverse problem with finite element analysis. 2D plaque models were derived from endarterectomy specimens of nine patients. Nonlinear neo-Hookean models (tissue elasticity C1) were assigned to fibrous intima, wall (i.e., media/adventitia), and lipid-rich necrotic core. Finite element analysis was used to simulate clinical cross-sectional US strain imaging. Computer-simulated, single-slice in vivo MR images were segmented by two MR readers. We investigated multiple scenarios for plaque model elasticity, and consistently found clear separations between estimated tissue elasticity values. The intima C1 (160 kPa scenario) was estimated as 125.8 ± 19.4 kPa (reader 1) and 128.9 ± 24.8 kPa (reader 2). The lipid-rich necrotic core C1 (5 kPa) was estimated as 5.6 ± 2.0 kPa (reader 1) and 8.5 ± 4.5 kPa (reader 2). A scenario with a stiffer wall yielded similar results, while realistic US strain noise and rotating the models had little influence, thus demonstrating robustness of the procedure. The promising findings of this computer-simulation study stimulate applying the proposed methodology in a clinical setting. PMID:26130603

  17. Detection of yellow fever virus: a comparison of quantitative real-time PCR and plaque assay

    Microsoft Academic Search

    Hi-Gung Bae; Andreas Nitsche; Anette Teichmann; Stefan S. Biel; Matthias Niedrig

    2003-01-01

    Yellow fever virus quantitation is performed routinely by cultivation of virus containing samples using susceptible cells. Counting of the resulting plaques provides a marker for the number of infectious particles present in the sample. This assay usually takes up to 5 days before results are obtained and must be carried out under L2 or L3 laboratory conditions, depending on the

  18. 169. 1932 MT. VERNON CHAPTER, N.S.D.A.R. MEMORIAL PLAQUE FOR VIRGINIA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    169. 1932 MT. VERNON CHAPTER, N.S.D.A.R. MEMORIAL PLAQUE FOR VIRGINIA PRESIDENTS AT BELLE HAVEN PICNIC AREA. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  19. Effect of hydrogen peroxide mouthwash as an adjunct to chlorhexidine on stains and plaque

    PubMed Central

    Jhingta, Pravesh; Bhardwaj, Ashu; Sharma, Deepak; Kumar, Naresh; Bhardwaj, Vinay Kumar; Vaid, Sanjeev

    2013-01-01

    Aim: To investigate whether the use of an oxidizing mouth rinse as an adjunct to chlorhexidine is efficacious in reducing stains and plaque. Materials and Methods: This study had a single-blind, three-group (n = 35 each) parallel design, including a 21 days experimental period during which group I rinsed with chlorhexidine (CHX) 0.2% alone, group II used chlorhexidine (CHX) followed by hydrogen peroxide (H2O2) 1.5%. Group III rinsed with the same mouthwashes in reverse order. Patients were randomly assigned to one of the three groups. The examination for plaque, and stains was done after 1, 2, and 3 weeks of rinsing. Results: Group II showed significantly less stain intensity in comparison with group I after 14 and 21 days (P values 0.025 and 0.005, respectively). The proportion of stained surfaces was less in the group II than in the group I and was significant at the end of 1 week. The plaque formation was significantly less in groups II and III than group I at 7, 14, and 21 days. Conclusion: The adjunctive use of hydrogen peroxide to chlorhexidine proved to be superior to chlorhexidine alone with regard to the inhibition of plaque and development of stains. PMID:24174723

  20. Outcome of coronary plaque burden: a 10-year follow-up of aggressive medical management

    Microsoft Academic Search

    Victor K Goh; Chu-Pak Lau; Stefan Mohlenkamp; John A Rumberger; Stephan Achenbach; Matthew J Budoff

    2010-01-01

    BACKGROUND: The effect of aggressive medical therapy on quantitative coronary plaque burden is not generally known, especially in ethnic Chinese. AIMS: We reasoned that Cardiac CT could conveniently quantify early coronary atherosclerosis in our patient population, and hypothesized that serial observation could differentiate the efficacy of aggressive medical therapy regarding progression and regression of the atherosclerotic process, as well as

  1. Mechanical response of a calcified plaque model to fluid shear force.

    PubMed

    Lin, Tiantian C; Tintut, Yin; Lyman, Althea; Mack, Wendy; Demer, Linda L; Hsiai, Tzung K

    2006-10-01

    Vascular calcification is associated with atherosclerosis, but whether it mechanically affects plaque stability remains controversial. To assess the effect of mineralization on plaque vulnerability to mechanical shear stress, we applied fluid shear to cultures of calcifying vascular cells (CVC), a subpopulation of smooth muscle cells that spontaneously mineralize. CVC cultures containing nodules were treated for 10 days with vehicle control or beta-glycerophosphate (BGP) to accelerate mineralization. Cultures were placed in a parallel-plate flow system and were subjected to increasing fluid shear stress (4.9 dyn/cm(2)/min up to 400 dyn/cm(2)). The number of nodules remaining attached was recorded every 10 min. Results showed that control cultures and BGP-treated cultures, which contained significantly greater calcium mineral than control cultures, had similar detachment thresholds (50-100 dyn/cm(2)), with linear portions of their stress/detachment curves from 100 to 275 dyn/cm(2). Based on repeated measure analysis of variance, BGP-treated nodules were no more likely to detach at a given shear than controls, although they showed a trend toward greater stability. Thus, calcification does not appear to increase plaque vulnerability to fluid shear stress, although it may contribute to a slight stabilization. This model may represent the first in vitro model of mechanical rupture of atherosclerotic plaque. PMID:17006755

  2. Testosterone as a protective factor against atherosclerosis--immunomodulation and influence upon plaque development and stability

    Microsoft Academic Search

    C J Malkin; P J Pugh; R D Jones; T H Jones; K S Channer

    2003-01-01

    Inflammation plays a central pathogenic role in the initia- tion and progression of coronary atheroma and its clinical consequences. Cytokines are the mediators of cellular inflammation and promote local inflammation in the arterial wall, which may lead to vascular smooth muscle apoptosis, degradation of the fibrin cap and plaque rup- ture. Platelet adhesion and thrombus formation then occur, resulting clinically

  3. Hydrolysis of Phosphates by Enzyme Preparations Derived from Carious Dentine, Bacterial Plaque and Saliva

    Microsoft Academic Search

    K. K. Mäkinen

    1970-01-01

    Enzyme preparations obtained from bacterial plaque, whole saliva and carious dentine were studied with respect to their ability to hydrolyze various phosphates. The substrates used were selected to represent the following biologically important phosphates: hydroxyalkyl phosphates, alkyl phosphates, enol phosphates, phosphoramidates, dialkyl phosphates, alkyl pyrophosphates, P1P2-dialkyl pyrophosphates, and alkyl triphosphates. The enzyme preparations exhibited a versatile reactivity pattern because all

  4. Noninvasive detection and evaluation of atherosclerotic coronary plaques with multislice computed tomography 1 1 This study was performed without additional financial support

    Microsoft Academic Search

    Stephen Schroeder; Andreas F Kopp; Andreas Baumbach; Christoph Meisner; Axel Kuettner; Christian Georg; Bernd Ohnesorge; Christian Herdeg; Claus D Claussen; Karl R Karsch

    2001-01-01

    OBJECTIVESThe aim of the present study was to evaluate the accuracy in determining coronary lesion configuration by multislice computed tomography (MSCT). The results were compared with the findings of intracoronary ultrasound (ICUS).BACKGROUNDThe risk of acute coronary syndromes caused by plaque disruption and thrombosis depends on plaque composition rather than stenosis severity. Thus, the reliable noninvasive assessment of plaque configuration would

  5. Comparative efficacy of two battery-powered toothbrushes on dental plaque removal.

    PubMed

    Ruhlman, C Douglas; Bartizek, Robert D; Biesbrock, Aaron R

    2002-01-01

    A number of clinical studies have consistently demonstrated that power toothbrushes deliver superior plaque removal compared to manual toothbrushes. Recently, a new power toothbrush (Crest SpinBrush) has been marketed with a design that fundamentally differs from other marketed power toothbrushes. Other power toothbrushes feature a small, round head designed to oscillate for enhanced cleaning between the teeth and below the gumline. The new power toothbrush incorporates a similar round oscillating head in conjunction with fixed bristles, which allows the user to brush with optimal manual brushing technique. The objective of this randomized, examiner-blind, parallel design study was to compare the plaque removal efficacy of a positive control power toothbrush (Colgate Actibrush) to an experimental toothbrush (Crest SpinBrush) following a single use among 59 subjects. Baseline plaque scores were 1.64 and 1.40 for the experimental toothbrush and control toothbrush treatment groups, respectively. With regard to all surfaces examined, the experimental toothbrush delivered an adjusted (via analysis of covariance) mean difference between baseline and post-brushing plaque scores of 0.47, while the control toothbrush delivered an adjusted mean difference of 0.33. On average, the difference between toothbrushes was statistically significant (p = 0.013). Because the covariate slope for the experimental group was statistically significantly greater (p = 0.001) than the slope for the control group, a separate slope model was used. Further analysis demonstrated that the experimental group had statistically significantly greater plaque removal than the control group for baseline plaque scores above 1.43. With respect to buccal surfaces, using a separate slope analysis of covariance, the experimental toothbrush delivered an adjusted mean difference between baseline and post-brushing plaque scores of 0.61, while the control toothbrush delivered an adjusted mean difference of 0.39. This difference between toothbrushes was also statistically significant (p = 0.002). On average, the results on lingual surfaces demonstrated similar directional scores favoring the experimental toothbrush; however these results did not achieve statistical significance. In conclusion, the experimental Crest SpinBrush, with its novel fixed and oscillating bristle design, was found to be more effective than the positive control Colgate Actibrush, which is designed with a small round oscillating cluster of bristles. PMID:11887517

  6. Computerized assessment of motion-contaminated calcified plaques in cardiac multidetector CT

    SciTech Connect

    King, Martin; Giger, Maryellen L.; Suzuki, Kenji; Bardo, Dianna M. E.; Greenberg, Brent; Lan Li; Pan Xiaochuan [Department of Radiology, Committee on Medical Physics, University of Chicago, Chicago, Illinois 60637 (United States)

    2007-12-15

    An automated method for evaluating the image quality of calcified plaques with respect to motion artifacts in noncontrast-enhanced cardiac computed tomography (CT) images is introduced. This method involves using linear regression (LR) and artificial neural network (ANN) regression models for predicting two patient-specific, region-of-interest-specific, reconstruction-specific and temporal phase-specific image quality indices. The first is a plaque motion index, which is derived from the actual trajectory of the calcified plaque and is represented on a continuous scale. The second is an assessability index, which reflects the degree to which a calcified plaque is affected by motion artifacts, and is represented on an ordinal five-point scale. Two sets of assessability indices were provided independently by two radiologists experienced in evaluating cardiac CT images. Inputs for the regression models were selected from 12 features characterizing the dynamic, morphological, and intensity-based properties of the calcified plaques. Whereas LR-velocity (LR-V) used only a single feature (three-dimensional velocity), the LR-multiple (LR-M) and ANN regression models used the same subset of these 12 features selected through stepwise regression. The regression models were parameterized and evaluated using a database of simulated calcified plaque images from the dynamic NCAT phantom involving nine heart rate/multi-sector gating combinations and 40 cardiac phases covering two cardiac cycles. Six calcified plaques were used for the plaque motion indices and three calcified plaques were used for both sets of assessability indices. In one configuration, images from the second cardiac cycle were used for feature selection and regression model parameterization, whereas images from the first cardiac cycle were used for testing. With this configuration, repeated measures concordance correlation coefficients (CCCs) and associated 95% confidence intervals for the LR-V, LR-M, and ANN were 0.817 [0.785, 0.848], 0.894 [0.869, 0.916], and 0.917 [0.892, 0.936] for the plaque motion indices. For the two sets of assessability indices, CCC values for the ANN model were 0.843 [0.791, 0.877] and 0.793 [0.747, 0.828]. These two CCC values were statistically greater than the CCC value of 0.689 [0.648, 0.727], which was obtained by comparing the two sets of assessability indices with each other. These preliminary results suggest that the variabilities of assessability indices provided by regression models can lie within the variabilities of the indices assigned by independent observers. Thus, the potential exists for using regression models and assessability indices for determining optimal phases for cardiac CT image interpretation.

  7. Histopathologic Characteristics of Atherosclerotic Coronary Disease and Implications of the Findings for the Invasive and Noninvasive Detection of Vulnerable Plaques

    PubMed Central

    Narula, Jagat; Nakano, Masataka; Virmani, Renu; Kolodgie, Frank D.; Petersen, Rita; Newcomb, Robert; Malik, Shaista; Fuster, Valentin; Finn, Aloke V.

    2014-01-01

    Objectives The goal of this study was to identify histomorphologic characteristics of atherosclerotic plaques and to determine the amenability of some of these components to be used as markers for invasive and noninvasive imaging. Background Rupture of the atherosclerotic plaques is responsible for the majority of acute coronary events, and the culprit lesions demonstrate distinct histopathologic features. It has been tacitly believed that plaque rupture (PR) is associated with angiographically minimally occlusive lesions. Methods We obtained 295 coronary atherosclerotic plaques, including stable (fibroatheroma [FA]; n = 105), vulnerable (thin-cap fibroatheroma [TCFA]; n = 88), and disrupted plaques (plaque rupture [PR]; n = 102) from the hearts of 181 men and 32 women who had died suddenly. The hierarchical importance of fibrous cap thickness, percent luminal stenosis, macrophage area, necrotic core area, and calcified plaque area was evaluated by using recursive partitioning analysis. Because clinical assessment of fibrous cap thickness is not possible by noninvasive imaging, it was excluded from the second set of partitioning analysis. Results Thickness of the fibrous cap emerged as the best discriminator of plaque type; the cap thickness measured <55 ?m in ruptured plaques, and all FA were associated with >84-?m cap thickness. Although the majority of TCFA were found in the 54- to 84-?m thickness group, those with <54-?m thickness were more likely to show <74% luminal stenosis (area under the curve: FA, 1.0; TCFA, 0.89; PR, 0.90). After exclusion of cap thickness, analysis of the plaque characteristics revealed macrophage infiltration and necrotic core to be the 2 best discriminators of plaque types (area under the curve: FA, 0.82; TCFA, 0.58; PR, 0.72). More than 75% cross-section area stenosis was seen in 70% of PR and 40% of TCFA; only 5% PR and 10% TCFA were <50% narrowed. Conclusions This postmortem study defines histomorphologic characteristics of vulnerable plaques, which may help develop imaging strategies for identification of such plaques in patients at a high risk of sustaining acute coronary events. PMID:23473409

  8. Les fractures distales de la clavicule type II de Neer: plaque à crochet versus brochage transacromiale

    PubMed Central

    Mechchat, Atif; Elidrissi, Mohammed; Shimi, Mohammed; Elibrahimi, Abdelhalim; Elmrini, Abdelmajid

    2015-01-01

    Cette étude a été menée afin de faire une comparaison entre deux techniques chirurgicales différentes: la plaque à crochet et l'embrochage dans les fractures instables du quart externe de la clavicule. Nous avons mené une étude prospective entre 2009 et 2013, incluant deux groupes de patients: un premier groupe de 14 patients traités par plaque à crochet par voie d'abord antéro-inférieure, un second de 12 patients traités par brochage. Tous les patients ont été hospitalisés 24 h après la chirurgie et ont été suivi pendant 1 an. Nous avons comparé les résultats des deux techniques en étudiant: le temps opératoire, le saignement, délai de consolidation, la douleur et la fonction selon le score de constant. L'analyse statistique des résultats fonctionnels et radiologiques a montré la supériorité d'une technique par rapport à l'autre; ainsi l’âge moyen global était de 32,6 ans (+/- 13,7), le sex-ratio (H/F) était de 1. Le temps opératoire moyen est de 35 min pour la plaque à crochet contre 45 minutes pour le brochage, le délai moyen de consolidation était de 6,1 (+/-0,7) semaines dans le groupe traité par plaque vissée, et de 6 (+/-0,7) semaines dans le groupe traité par embrochage (p = 0,5), le score de Constant absolu moyen était respectivement de 86 (+/-10,4) et de 90,92 (+/-2,5) (p = 0,04). L'analyse uni variée a montré une association statistiquement significative entre les paramètres d’évaluation et les deux techniques chirurgicales étudiées. Par conséquent, l’étude a noté la supériorité de la plaque à crochet contre l'embroche dans les fractures instables du quart externe de la clavicule.

  9. Leptin Locally Synthesized in Carotid Atherosclerotic Plaques Could Be Associated With Lesion Instability and Cerebral Emboli

    PubMed Central

    Schneiderman, Jacob; Schaefer, Katrin; Kolodgie, Frank D.; Savion, Naphtali; Kotev-Emeth, Shlomo; Dardik, Rima; Simon, Amos J.; Halak, Moshe; Pariente, Clara; Engelberg, Isaac; Konstantinides, Stavros; Virmani, Renu

    2012-01-01

    Background Unstable carotid plaques cause cerebral emboli. Leptin promotes atherosclerosis and vessel wall remodeling. We hypothesized that carotid atherosclerotic lesion instability is associated with local leptin synthesis. Methods and Results Carotid endarterectomy plaques from symptomatic (n=40) and asymptomatic patients with progressive stenosis (n=38) were analyzed for local expression of leptin, tumor necrosis factor (TNF)-?, and plasminogen activator inhibitor type 1. All lesions exhibited advanced atherosclerosis inclusive of thick- and thin-cap fibroatheromas or lesion rupture. Symptomatic lesions exhibited more plaque ruptures and macrophage infiltration (P=0.001 and P=0.05, respectively). Symptomatic plaques showed preferential leptin, TNF-?, and plasminogen activator inhibitor type 1 transcript (P=0.03, P=0.04, and P=0.05, respectively). Leptin mRNA and antigen in macrophages and smooth muscle cells were confirmed by in situ hybridization and immunohistochemistry. Plasma leptin levels were not significantly different between groups (P=1.0), whereas TNF-? was significantly increased in symptomatic patients (P=0.006). Human aortic smooth muscle cell culture stimulated by TNF-?, lipopolysaccharide, or lipoteichoic acid revealed 6-, 6.7-, and 6-fold increased secreted leptin antigen, respectively, at 72 hours (P<0.05). Conclusions Neurologically symptomatic patients overexpress leptin mRNA and synthesize leptin protein in carotid plaque macrophages and smooth muscle cells. Local leptin induction, presumably by TNF-?, could exert paracrine or autocrine effects, thereby contributing to the pathogenesis of lesion instability. Clinical Trial Registration URL: www.Clinicaltrials.gov. Unique identifier: NCT00449306. PMID:23316287

  10. Detection of pleural plaques in workers exposed to inhalation of natural fluoro-edenite fibres

    PubMed Central

    RAPISARDA, VENERANDO; LEDDA, CATERINA; RICCERI, VINCENZO; ARENA, FRANCESCO; MUSUMECI, ANDREA; MARCONI, ANDREA; FAGO, LUCREZIA; BRACCI, MASSIMO; SANTARELLI, LORY; FERRANTE, MARGHERITA

    2015-01-01

    Fluoro-edenite is a natural mineral species initially isolated in Biancavilla, Sicily. The fibres are similar in size and morphology to certain amphibolic asbestos fibres, the inhalation of which may cause chronic inflammation and cancer. Occupational asbestos exposure is known to be associated with pleural and lung diseases, including pleural plaques. The aim of this study was to report the pleural and lung parenchymal lesions detected by high-resolution computed tomography (HRCT) in a group of construction workers exposed to fluoro-edenite. Information regarding life habits and occupational history was collected from 43 workers enrolled into the study. The participants underwent physical examination, blood analysis, search for uncoated fibres and ferruginous bodies in the sputum, pulmonary function tests, including diffusion capacity for carbon monoxide (TLCO), and HRCT chest imaging. A general descriptive outcome analysis was also conducted; a prevalence ratio (PR) with 95% confidence interval and a two-tailed test P-value were calculated for pleural plaques using log-binomial regression, measuring plaque size and thickness, and cumulative exposure index (CEI). The mean values of the functional respiratory tests were within the normal range for all participants. A restrictive ventilatory defect was identified in two (5%) subjects and an obstructive ventilatory defect in three (7%) subjects. TLCO was reduced in two additional participants. Fibres were detected in 19 (44%) of subjects. Pleural involvement was documented in 39 (91%) workers, of whom 31 (72%) had bilateral plaques. Calcifications were detected in 25 (58%) of these participants. PR indicated a progressive increase in the risk of developing pleural lesions with rising CEI, i.e. length of exposure. The present findings demonstrate for the first time the presence of pleural plaques in the lungs of subjects exposed to fluoro-edenite fibres, and not to asbestos, through residing in Biancavilla and through their occupation.

  11. Repeated episodes of thrombosis as a potential mechanism of plaque progression in cardiac allograft vasculopathy

    PubMed Central

    Matsuo, Yoshiki; Cassar, Andrew; Li, Jing; Flammer, Andreas J.; Choi, Byoung-Joo; Herrmann, Joerg; Gulati, Rajiv; Lennon, Ryan J.; Kang, Soo-Jin; Maehara, Akiko; Kitabata, Hironori; Akasaka, Takashi; Lerman, Lilach O.; Kushwaha, Sudhir S.; Lerman, Amir

    2013-01-01

    Aims The pathogenesis of cardiac allograft vasculopathy (CAV) remains complex and may involve multiple mechanisms. We tested the hypothesis that the multilayer (ML) appearance, an intravascular ultrasound (IVUS) finding suggestive of repetitive thrombosis, is associated with plaque progression in heart transplant (HTx) recipients. Methods and results Our study population consisted of 132 HTx recipients undergoing at least two grayscale and virtual histology (VH)-IVUS examinations. A retrospective serial analysis was performed between the first (baseline) and the last (follow-up) IVUS data during a median follow-up of 3.0 years. The subjects were divided into two groups based on the presence of the ML appearance on the baseline IVUS. At baseline, subjects with ML appearance (n = 38) had a longer time elapsed since transplant, larger vessel volume, and larger plaque volume than those without (n = 94) (all P < 0.01). Intraluminal thrombi and plaque ruptures were identified only in subjects with ML appearance (P < 0.01 vs. those without). More subjects with ML appearance at baseline developed subsequent ML formation compared with those without [21 (55%) vs. 22 (23%), P < 0.01] during follow-up. There was an increase in plaque volume, necrotic core volume, and dense calcium volume in subjects with ML appearance (all P < 0.01 vs. those without). Multivariable linear regression analysis showed that ML appearance was a potential predictor of plaque progression (regression coefficient 0.28, 95% CI 0.10–0.45, P < 0.01). Conclusions The current study demonstrates that a finding of ML appearance, indicative of repeated episodes of mural thrombosis, is not infrequent in asymptomatic HTx recipients and possibly contributes to progression of CAV. PMID:23782648

  12. Enhancing Astrocytic Lysosome Biogenesis Facilitates A? Clearance and Attenuates Amyloid Plaque Pathogenesis

    PubMed Central

    Xiao, Qingli; Yan, Ping; Ma, Xiucui; Liu, Haiyan; Perez, Ronaldo; Zhu, Alec; Gonzales, Ernesto; Burchett, Jack M.; Schuler, Dorothy R.; Cirrito, John R.

    2014-01-01

    In sporadic Alzheimer's disease (AD), impaired A? removal contributes to elevated extracellular A? levels that drive amyloid plaque pathogenesis. Extracellular proteolysis, export across the blood–brain barrier, and cellular uptake facilitate physiologic A? clearance. Astrocytes can take up and degrade A?, but it remains unclear whether this function is insufficient in AD or can be enhanced to accelerate A? removal. Additionally, age-related dysfunction of lysosomes, the major degradative organelles wherein A? localizes after uptake, has been implicated in amyloid plaque pathogenesis. We tested the hypothesis that enhancing lysosomal function in astrocytes with transcription factor EB (TFEB), a master regulator of lysosome biogenesis, would promote A? uptake and catabolism and attenuate plaque pathogenesis. Exogenous TFEB localized to the nucleus with transcriptional induction of lysosomal biogenesis and function in vitro. This resulted in significantly accelerated uptake of exogenously applied A?42, with increased localization to and degradation within lysosomes in C17.2 cells and primary astrocytes, indicating that TFEB is sufficient to coordinately enhance uptake, trafficking, and degradation of A?. Stereotactic injection of adeno-associated viral particles carrying TFEB driven by a glial fibrillary acidic protein promoter was used to achieve astrocyte-specific expression in the hippocampus of APP/PS1 transgenic mice. Exogenous TFEB localized to astrocyte nuclei and enhanced lysosome function, resulting in reduced A? levels and shortened half-life in the brain interstitial fluid and reduced amyloid plaque load in the hippocampus compared with control virus-injected mice. Therefore, activation of TFEB in astrocytes is an effective strategy to restore adequate A? removal and counter amyloid plaque pathogenesis in AD. PMID:25031402

  13. Automatic plaque characterization and vessel wall segmentation in magnetic resonance images of atherosclerotic carotid arteries

    NASA Astrophysics Data System (ADS)

    Adame, Isabel M.; van der Geest, Rob J.; Wasserman, Bruce A.; Mohamed, Mona; Reiber, Johan H. C.; Lelieveldt, Boudewijn P. F.

    2004-05-01

    Composition and structure of atherosclerotic plaque is a primary focus of cardiovascular research. In vivo MRI provides a meanse to non-invasively image and assess the morphological features of athersclerotic and normal human carotid arteries. To quantitatively assess the vulnerability and the type of plaque, the contours of the lumen, outer boundary of the vessel wall and plaque components, need to be traced. To achieve this goal, we have developed an automated contou detection technique, which consists of three consecutive steps: firstly, the outer boundary of the vessel wall is detected by means of an ellipse-fitting procedure in order to obtain smoothed shapes; secondly, the lumen is segnented using fuzzy clustering. Thre region to be classified is that within the outer vessel wall boundary obtained from the previous step; finally, for plaque detection we follow the same approach as for lumen segmentation: fuzzy clustering. However, plaque is more difficult to segment, as the pixel gray value can differ considerably from one region to another, even when it corresponds to the same type of tissue. That makes further processing necessary. All these three steps might be carried out combining information from different sequences (PD-, T2-, T1-weighted images, pre- and post-contrast), to improve the contour detection. The algorithm has been validated in vivo on 58 high-resolution PD and T1 weighted MR images (19 patients). The results demonstrate excellent correspondence between automatic and manual area measurements: lumen (r=0.94), outer (r=0.92), and acceptable for fibrous cap thickness (r=0.76).

  14. Modulation of the Myxoma Virus Plaque Phenotype by Vaccinia Virus Protein F11

    PubMed Central

    Irwin, Chad R.

    2012-01-01

    Vaccinia virus (VACV) produces large plaques consisting of a rapidly expanding ring of infected cells surrounding a lytic core, whereas myxoma virus (MYXV) produces small plaques that resemble a focus of transformed cells. This is odd, because bioinformatics suggests that MYXV carries homologs of nearly all of the genes regulating Orthopoxvirus attachment, entry, and exit. So why does MYXV produce foci? One notable difference is that MYXV-infected cells produce few of the actin microfilaments that promote VACV exit and spread. This suggested that although MYXV carries homologs of the required genes (A33R, A34R, A36R, and B5R), they are dysfunctional. To test this, we produced MYXV recombinants expressing these genes, but we could not enhance actin projectile formation even in cells expressing all four VACV proteins. Another notable difference between these viruses is that MYXV lacks a homolog of the F11L gene. F11 inhibits the RhoA-mDia signaling that maintains the integrity of the cortical actin layer. We constructed an MYXV strain encoding F11L and observed that, unlike wild-type MYXV, the recombinant virus disrupted actin stress fibers and produced plaques up to 4-fold larger than those of controls, and these plaques expanded ?6-fold faster. These viruses also grew to higher titers in multistep growth conditions, produced higher levels of actin projectiles, and promoted infected cell movement, although neither process was to the extent of that observed in VACV-infected cells. Thus, one reason for why MYXV produces small plaques is that it cannot spread via actin filaments, although the reason for this deficiency remains obscure. A second reason is that leporipoxviruses lack vaccinia's capacity to disrupt cortical actin. PMID:22514354

  15. Intermittent cold stress enhances features of atherosclerotic plaque instability in apolipoprotein E?deficient mice.

    PubMed

    Zheng, Xi; Wang, Qiang; Zhang, Yan; Yang, Dachun; Li, De; Tang, Bing; Li, Xiuchuan; Yang, Yongjian; Ma, Shuangtao

    2014-10-01

    The cold weather is associated with an increased occurrence of acute coronary events. However, the mechanisms underlying cold?induced myocardial infarctions have not yet been fully elucidated. In the present study, 20 male, eight week?old, apolipoprotein E (ApoE)?deficient mice were subjected to either control conditions or intermittent cold exposure for eight weeks. Mice in the cold group were placed in a cold room at 4?C for 4 h per day, while the mice in the control group were kept in a room at 24?C. Cold?exposed mice did not significantly differ from control mice in body weight, fasting glucose concentration and plasma lipid levels, including triglyceride, total cholesterol, low?density lipoprotein and high?density lipoprotein. The hematoxylin and eosin?stained sections of the aortic root demonstrated increased plaque size in the cold group compared with the control group (P<0.01). Furthermore, cold?treated mice exhibited significantly decreased plaque collagen and vascular smooth muscle cell deposition and increased macrophage and lymphocyte content (P<0.05 or P<0.01), which are typical features of atherosclerotic plaque instability. Additionally, the protein expression of matrix metalloproteinase (MMP)?2, MMP?9 and MMP?14 were significantly increased (P<0.05 or P<0.01), whereas tissue inhibitor of matrix metalloproteinase (TIMP)?1 expression was decreased (P<0.05) following exposure to a cold environment. The present study demonstrated that chronic intermittent cold stress may increase atherosclerotic plaque size and promote plaque instability in ApoE?deficient mice by altering the balance of MMPs and TIMPs. These findings may provide mechanistic insights into sudden cardiac death in cold environments. PMID:25109747

  16. Bone marrow endothelial progenitors augment atherosclerotic plaque regression in a mouse model of plasma lipid lowering

    PubMed Central

    Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Iida, Ryuji; Wang, Qilong; Zou, Ming-Hui; Barlic-Dicen, Jana

    2012-01-01

    The major event initiating atherosclerosis is hypercholesterolemia-induced disruption of vascular endothelium integrity. In settings of endothelial damage, endothelial progenitor cells (EPCs) are mobilized from bone marrow into circulation and home to sites of vascular injury where they aid endothelial regeneration. Given the beneficial effects of EPCs in vascular repair, we hypothesized that these cells play a pivotal role in atherosclerosis regression. We tested our hypothesis in the atherosclerosis-prone mouse model in which hypercholesterolemia, one of the main factors affecting EPC homeostasis, is reversible (Reversa mice). In these mice normalization of plasma lipids decreased atherosclerotic burden; however, plaque regression was incomplete. To explore whether endothelial progenitors contribute to atherosclerosis regression, bone marrow EPCs from a transgenic strain expressing green fluorescent protein under the control of endothelial cell-specific Tie2 promoter (Tie2-GFP+) were isolated. These cells were then adoptively transferred into atheroregressing Reversa recipients where they augmented plaque regression induced by reversal of hypercholesterolemia. Advanced plaque regression correlated with engraftment of Tie2-GFP+ EPCs into endothelium and resulted in an increase in atheroprotective nitric oxide and improved vascular relaxation. Similarly augmented plaque regression was also detected in regressing Reversa mice treated with the stem cell mobilizer AMD3100 which also mobilizes EPCs to peripheral blood. We conclude that correction of hypercholesterolemia in Reversa mice leads to partial plaque regression that can be augmented by AMD3100 treatment or by adoptive transfer of EPCs. This suggests that direct cell therapy or indirect progenitor cell mobilization therapy may be used in combination with statins to treat atherosclerosis. PMID:23081735

  17. Assessment of an elastin binding molecule for PET imaging of atherosclerotic plaques

    PubMed Central

    Fischer, Cindy R; Müller, Adrienne; Bochsler, Bianca; Rancic, Zoran; Kaufmann, Philipp; Schibli, Roger; Ametamey, Simon M

    2013-01-01

    Elastin is considered as a key player in human vascular diseases and it might contribute to the development of atherosclerosis. The elastin binding radiotracer, [18F]AlF-NOTA-EBM ([18F]2), was evaluated in a wild type mouse to determine its in vivo distribution and on human carotid atherosclerotic plaque tissues to assess its utility as a PET imaging agent for visualizing human atherosclerotic plaque lesions. The free ligand NOTA-EBM, which served as the precursor, was obtained in 25% chemical yield. The radiosynthesis of [18F]2 was accomplished by coordination of Al18F to NOTA-EBM in 8-13% decay corrected radiochemical yield (n = 7) and specific radioactivity of 59 ± 12 GBq/?mol. A dynamic in vivo PET scan in a healthy wild type mouse (C57BL/6) showed high accumulation of radioactivity in heart and lungs, organs reported to have high elastin content. Excretion of [18F]2 proceeded via the renal pathway and through the hepatobiliary system as indicated by a high uptake of radioactivity in the liver, intestines and gall bladder. In vitro autoradiography on human atherosclerotic plaque sections showed a heterogeneous distribution of [18F]2 with an elevated accumulation in stable and vulnerable atherosclerotic plaques compared to control samples of normal arteries. However, there was no statistical significance between the different plaque phenotypes and control samples. Competition experiments with 10.000-fold excess of free ligand NOTA-EBM resulted in a marked decrease of radioactivity accumulation, consistent with a target-specific ligand. PMID:23901358

  18. Functional deprivation promotes amyloid plaque pathogenesis in Tg2576 mouse olfactory bulb and piriform cortex

    PubMed Central

    Zhang, Xue-Mei; Xiong, Kun; Cai, Yan; Cai, Huaibin; Luo, Xue-Gang; Feng, Jia-Chun; Clough, Richard W.; Patrylo, Peter R.; Struble, Robert G.; Yan, Xiao-Xin

    2010-01-01

    Cerebral hypometabolism and amyloid accumulation are principal neuropathological manifestations of Alzheimer’s disease (AD). Whether and how brain/neuronal activity might modulate certain pathological process of AD are interesting topics of recent clinical and basic research in the field, and may be of potential medical relevance in regard to both the disease etiology and intervention. Using the Tg2576 transgenic mouse model of AD, this study characterized a promotive effect of neuronal hypoactivity associated with functional deprivation on amyloid plaque pathogenesis in the olfactory pathway. Unilateral naris-occlusion caused BACE1 elevation in neuronal terminals in the deprived relative to the non-deprived bulb and piriform cortex in young adult mice. In parallel with the overall age-related plaque development in the forebrain, locally-increased BACE1 immunoreactivity co-occurred with amyloid deposition first in the piriform cortex then within the bulb, more prominent on the deprived relative to the non-deprived side. Biochemical analyses confirmed elevated BACE1 protein levels, enzymatic activity and products in the deprived relative to non-deprived bulbs. Plaque-associated BACE1 immunoreactivity in the bulb and piriform cortex was localized preferentially to swollen/sprouting glutamatergic axonal terminals, with A? immunoreactivity occurred inside as well as around these terminals. Together, these findings suggest that functional deprivation or neuronal hypoactivity facilitates amyloid plaque formation in the forebrain in a transgenic model of AD, which operates synergistically with age effect. The data also implicate an intrinsic association of amyloid accumulation and plaque formation with progressive axonal pathology. PMID:20384814

  19. Community-level assessment of dental plaque bacteria susceptibility to triclosan over 19 years

    PubMed Central

    2014-01-01

    Background Triclosan is a broad-spectrum antimicrobial agent used in toothpaste to reduce dental plaque, gingivitis and oral malodor. This community-level assessment evaluated the susceptibility of dental plaque bacteria to triclosan in samples collected over 19 years. Methods A total of 155 dental plaque samples were collected at eleven different times over 19 years from 58 adults using 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride toothpaste and from 97 adults using toothpaste without triclosan. These included samples from 21 subjects who used triclosan toothpaste for at least five years and samples from 20 control subjects. The samples were cultured on media containing 0, 7.5 or 25 ?g/ml triclosan. Descriptive statistics and p values were computed and a linear regression model and the runs test were used to examine susceptibility over time. Results Growth inhibition averaged 99.451% (91.209 - 99.830%) on media containing 7.5 ?g/ml triclosan and 99.989% (99.670 - 100%) on media containing 25 ?g/ml triclosan. There was no change in microbial susceptibility to triclosan over time discernible by regression analysis or the runs test in plaque samples taken over 19 years including samples from subjects using a triclosan-containing dentifrice for at least five years. Conclusions This community-level assessment of microbial susceptibility to triclosan among supragingival plaque bacteria is consistent with the long-term safety of a 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride dentifrice. PMID:24889743

  20. Circulating CD36 and fractalkine levels are associated with vulnerable plaque progression in patients with unstable angina pectoris.

    PubMed

    Li, Rui Jian; Yang, Ming; Li, Ji Fu; Xue, Li; Chen, Yu Guo; Chen, Wen Qiang

    2014-11-01

    The chemokine, fractalkine, independently enhances the vulnerability of coronary atherosclerotic plaques. The present study investigated the combined effects of CD36 and fractalkine on coronary plaque progression in patients with unstable angina pectoris. In the present study, 120 unstable angina pectoris patients undergoing coronary angiography and intravascular ultrasound were divided into two groups: an intermediate lesion group (lumen diameter stenosis 50-70%, 80 patients) and a severe lesion group (at least one lesion with lumen diameter stenosis > 70%, 40 patients). The control group consisted of 40 healthy age- and sex-matched subjects. Concentrations of CD36 and fractalkine were measured by enzyme-linked immunosorbent assay. Major adverse cardiovascular events were monitored over a 2-year follow up. Intravascular ultrasound showed that patients with severe lesions had more calcified and mixed plaques, and a larger plaque area and plaque burden than patients with intermediate lesions (P < 0.05-0.01). More patients with severe lesions underwent stent deployment (P < 0.05) than those with intermediate lesions. CD36 and fractalkine concentrations were significantly higher in the severe lesion patients (P < 0.05), and both had significant positive correlations (P < 0.05) with the plaque burden of atherosclerotic lesions. Using the matched nested case-control study, we found that CD36 and fractalkine levels were higher in patients with recurrent major adverse cardiovascular events than controls (P < 0.05). In conclusion, CD36 and fractalkine both promote, and might synergistically enhance, the progression of coronary atherosclerotic plaques. PMID:25224515

  1. The comparative effect of propolis in two different vehicles; mouthwash and chewing-gum on plaque accumulation and gingival inflammation

    PubMed Central

    Ercan, Nuray; Erdemir, Ebru Olgun; Ozkan, Serdar Yucel; Hendek, Meltem Karsiyaka

    2015-01-01

    Objective: In general, chemical plaque agents have been used in mouthwashes, gels, and dentifrices. In some situations, application of mouthwashes and dentifrices can be difficult. Therefore, different approaches for oral health-care have been needed. The aim of this study was to evaluate the effect of propolis chewing-gum compared to propolis-containing mouthwash on gingival inflammation and plaque accumulation on patients that refrained from daily oral hygiene procedures for 5 days. Materials and Methods: 10 college students with systemically healthy and very good oral hygiene and gingival health were included in this randomized, single-blind, crossover 5-day plaque regrowth with a 3-day washout period clinical study. After plaque scores were reduced to zero, participants were asked to refrain from oral hygiene procedures and allocated to either propolis mouthwash or chewing-gum group. Chewing-gum was performed after meals 3 times a day for 20 min mouthwash group was instructed to rinse mouthwash 2 times a day for 1 min. On day 5, the clinical periodontal measurements containing plaque and gingival indexes were taken from the participants. Results: The both plaque and gingival indexes of propolis mouthwash group were significantly lower than that of the propolis chewing-gum group (P = 0.005). Conclusion: It was demonstrated that the propolis mouthwash was more effective than the propolis chewing gum on the plaque inhibition and the gingival inflammation.

  2. The Association between Serum Uric Acid Levels and the Prevalence of Vulnerable Atherosclerotic Carotid Plaque: A Cross-sectional Study

    PubMed Central

    Li, Qing; Zhou, Yong; Dong, Kehui; Wang, Anxin; Yang, Xin; Zhang, Caifeng; Zhu, Yi; Wu, Shouling; Zhao, Xingquan

    2015-01-01

    Little is known about the associations between serum uric acid (SUA) levels and atherosclerotic carotid plaque vulnerability. The aim of this study was to assess the associations of SUA levels with the prevalence of vulnerable atherosclerotic carotid plaque in a community-based cohort. In the Asymptomatic Polyvascular Abnormalities Community (APAC) study, cross-sectional data from 2860 Chinese residents who underwent SUA measurement and ultrasonographic assessment of carotid plaque were analyzed. Multivariable logistic regression models were used to assess the associations of SUA levels with presence of vulnerable carotid plaque. After adjustment for potential confounders, SUA levels were significantly associated with the prevalence of vulnerable plaque amongst the middle-aged adults (odds ratio [OR]?=?1.19, 95% confidence interval [CI]: 1.11–1.28). Compared to the lowest quartile, quartiles 2, 3 and 4 had a prevalence OR of 1.33 (1.02–1.74), 1.70 (1.27–2.27) and 2.05 (1.53–2.75), respectively, for the presence of vulnerable carotid plaque (p for trend across quartiles?plaque in middle-aged adults. PMID:25961501

  3. Perforin and Granzyme B Have Separate and Distinct Roles during Atherosclerotic Plaque Development in Apolipoprotein E Knockout Mice

    PubMed Central

    Hiebert, Paul R.; Boivin, Wendy A.; Zhao, Hongyan; McManus, Bruce M.; Granville, David J.

    2013-01-01

    The granzyme B/perforincytotoxic pathway is a well established mechanism of initiating target cell apoptosis. Previous studies have suggested a role for the granzyme B/perforin cytotoxic pathway in vulnerable atherosclerotic plaque formation. In the present study, granzyme B deficiency resulted in reduced atherosclerotic plaque development in the descending aortas of apolipoprotein E knockout mice fed a high fat diet for 30 weeks while perforindeficiency resulted in greater reduction in plaque development with significantly less plaque area than granzyme Bdeficient mice. In contrast to the descending aorta, no significant change in plaque size was observed in aortic roots from either granzyme Bdeficient or perforindeficient apolipoprotein E knockout mice. However, atherosclerotic plaques in the aortic roots did exhibit significantly more collagen in granzyme B, but not perforin deficient mice. Together these results suggest significant, yet separate roles for granzyme B and perforin in the pathogenesis of atherosclerosis that go beyond the traditional apoptotic pathway with additional implications in plaque development, stability and remodelling of extracellular matrix. PMID:24205352

  4. Necrotic core thickness and positive arterial remodeling index: emergent biomechanical factors for evaluating the risk of plaque rupture.

    PubMed

    Ohayon, Jacques; Finet, Gérard; Gharib, Ahmed M; Herzka, Daniel A; Tracqui, Philippe; Heroux, Julie; Rioufol, Gilles; Kotys, Melanie S; Elagha, Abdalla; Pettigrew, Roderic I

    2008-08-01

    Fibrous cap thickness is often considered as diagnostic of the degree of plaque instability. Necrotic core area (Core(area)) and the arterial remodeling index (Remod(index)), on the other hand, are difficult to use as clinical morphological indexes: literature data show a wide dispersion of Core(area) thresholds above which plaque becomes unstable. Although histopathology shows a strong correlation between Core(area) and Remod(index), it remains unclear how these interact and affect peak cap stress (Cap(stress)), a known predictor of rupture. The aim of this study was to investigate the change in plaque vulnerability as a function of necrotic core size and plaque morphology. Cap(stress) value was calculated on 5,500 idealized atherosclerotic vessel models that had the original feature of mimicking the positive arterial remodeling process described by Glagov. Twenty-four nonruptured plaques acquired by intravascular ultrasound on patients were used to test the performance of the associated idealized morphological models. Taking advantage of the extensive simulations, we investigated the effects of anatomical plaque features on Cap(stress). It was found that: 1) at the early stages of positive remodeling, lesions were more prone to rupture, which could explain the progression and growth of clinically silent plaques and 2) in addition to cap thickness, necrotic core thickness, rather than area, was critical in determining plaque stability. This study demonstrates that plaque instability is to be viewed not as a consequence of fibrous cap thickness alone but rather as a combination of cap thickness, necrotic core thickness, and the arterial remodeling index. PMID:18586893

  5. Image-Based Modeling and Precision Medicine: Patient-Specific Carotid and Coronary Plaque Assessment and Predictions

    PubMed Central

    Yang, Chun; Zheng, Jie; Canton, Gador; Bach, Richard; Hatsukami, Thomas S.; Wang, Liang; Yang, Deshan; Billiar, Kristen L.; Yuan, Chun

    2013-01-01

    Atherosclerotic plaques may rupture without warning and cause acute cardiovascular events such as heart attack and stroke. Current clinical screening tools are insufficient to identify those patients with risks early and prevent the adverse events from happening. Medical imaging and image-based modeling have made considerable progress in recent years in identifying plaque morphological and mechanical risk factors which may be used in developing improved patient screening strategies. The key steps and factors in image-based models for human carotid and coronary plaques were illustrated, as well as grand challenges facing the researchers in the field to develop more accurate screening tools. PMID:23362245

  6. Plaque morphology and pathogenicity for newborn mice of swine vesicular disease virus. I. Wild strains and their clones.

    PubMed

    Niemia?towski, M

    1983-05-01

    The population of wild swine vesicular disease virus (SVDV) strains was found non-homogeneous as manifested by varying plaque size and different pathogenicity of the clones obtained. The clones derived from large plaques (5-9 mm)--dominating among wild strains--were more virulent for newborn mice than those obtained from smaller plaques (1-2 mm). To evaluate the pathogenicity of wild SVDV strains the dose index was calculated; the clones were compared by dose index and theoretical pathogenicity index, respectively. PMID:6138982

  7. A standardized method to automatically segment amyloid plaques in Congo Red stained sections from Alzheimer transgenic mice.

    PubMed

    Teboul, Olivier; Feki, Abdelmonem; Dubois, Albertine; Bozon, Bruno; Faure, Alexis; Hantraye, Philippe; Dhenain, Marc; Delatour, Benoit; Delzescaux, Thierry

    2007-01-01

    Automated detection of amyloid plaques (AP) in post mortem brain sections of patients with Alzheimer disease (AD) or in mouse models of the disease is a major issue to improve quantitative, standardized and accurate assessment of neuropathological lesions as well as of their modulation by treatment. We propose a new segmentation method to automatically detect amyloid plaques in Congo Red stained sections based on adaptive thresholds and a dedicated amyloid plaque/tissue modelling. A set of histological sections focusing on anatomical structures was used to validate the method in comparison to expert segmentation. PMID:18003280

  8. Material properties of components in human carotid atherosclerotic plaques: A uniaxial extension study

    PubMed Central

    Teng, Zhongzhao; Zhang, Yongxue; Huang, Yuan; Feng, Jiaxuan; Yuan, Jianmin; Lu, Qingsheng; Sutcliffe, Michael P.F.; Brown, Adam J.; Jing, Zaiping; Gillard, Jonathan H.

    2014-01-01

    Computational modelling to calculate the mechanical loading within atherosclerotic plaques has been shown to be complementary to defining anatomical plaque features in determining plaque vulnerability. However, its application has been partially impeded by the lack of comprehensive knowledge about the mechanical properties of various tissues within the plaque. Twenty-one human carotid plaques were collected from endarterectomy. The plaque was cut into rings, and different type of atherosclerotic tissues, including media, fibrous cap (FC), lipid and intraplaque haemorrhage/thrombus (IPH/T) was dissected for uniaxial extension testing. In total, 65 media strips from 17 samples, 59 FC strips from 14 samples, 38 lipid strips from 11 samples, and 21 IPH/T strips from 11 samples were tested successfully. A modified Mooney–Rivlin strain energy density function was used to characterize the stretch–stress relationship. The stiffnesses of media and FC are comparable, as are lipid and IPH/T. However, both media and FC are stiffer than either lipid or IPH/T. The median values of incremental Young’s modulus of media, FC, lipid and IPH/T at ? = 1 are 290.1, 244.5, 104.4, 52.9, respectively; they increase to 1019.5, 817.4, 220.7 and 176.9 at ? = 1.1; and 4302.7, 3335.0, 533.4 and 268.8 at ? = 1.15 (unit, kPa; ?, stretch ratio). The material constants of each tissue type are suggested to be: media, c1 = 0.138 kPa, D1 = 3.833 kPa and D2 = 18.803; FC, c1 = 0.186 kPa, D1 = 5.769 kPa and D2 = 18.219; lipid, c1 = 0.046 kPa, D1 = 4.885 kPa and D2 = 5.426; and IPH/T, c1 = 0.212 kPa, D1 = 4.260 kPa and D2 = 5.312. It is concluded that all soft atherosclerotic tissues are non-linear, and both media and FC are stiffer than either lipid or IPH/T. PMID:25200842

  9. Clinical study results of desoximetasone spray, 0.25% in moderate to severe plaque psoriasis.

    PubMed

    Kircik, Leon; Lebwohl, Mark G; Del Rosso, James Q; Bagel, Jerry; Stein Gold, Linda; Weiss, Jonathan S

    2013-12-01

    Two Phase 3, double-blind, randomized, vehicle-controlled parallel studies evaluated the efficacy and safety of desoximetasone spray 0.25%, a super-potent topical corticosteroid, twice daily vs vehicle spray twice daily for 28 days in adult patients with moderate to severe plaque psoriasis. At baseline and throughout the study, the severity of disease for the psoriatic lesions was assessed using the Physician Global Assessment (PGA) score and a target lesion was assessed using the Total Lesion Severity Score (TLSS). A designated psoriatic plaque lesion was selected as the target lesion upon enrollment and evaluated throughout the study to determine the TLSS. To qualify for study entry, the subject needed to exhibit a PGA score of 3 (moderate) or 4 (severe) for overall disease severity, and a target lesion with an area of at least 5 cm(2) that achieved a combined score TLSS of >=7, with a plaque elevation score of >=3 (at least moderate). The mean % BSA affected by psoriasis ranged from 13%-17% at baseline. In both Phase 3 studies, a statistically significantly greater percentage of subjects in the desoximetasone spray 0.25% compared to vehicle group achieved both Clinical Success and Treatment Success at Day 28. These results, which were the primary efficacy variables, demonstrated superior efficacy in the active study group for both overall improvement of plaque psoriasis (by PGA) and in the individual psoriasis lesion (by TLSS) designated at baseline as the most severely involved plaque (target lesion). Assessment of secondary efficacy variables in both Phase 3 studies showed that subjects receiving desoximetasone Spray 0.25% twice daily exhibited statistically significantly mean changes from Baseline to Day 28 in PGA, TLSS, and % BSA affected when compared to subjects receiving vehicle spray twice daily. Tolerability and safety were assessed at all study visits. No statistically significant differences were observed between study arms and no major safety signals related to AEs were noted. No stinging and burning were reported with the spray formulation. This Class I topical corticosteroid has shown to be safe and efficacious in moderate to severe plaque psoriasis. PMID:24301242

  10. Requirements for imaging vulnerable plaque in the coronary artery using a coded aperture imaging system

    NASA Astrophysics Data System (ADS)

    Tozian, Cynthia

    A coded aperture1 plate was employed on a conventional gamma camera for 3D single photon emission computed tomography (SPECT) imaging on small animal models. The coded aperture design was selected to improve the spatial resolution and decrease the minimum detectable activity (MDA) required to image plaque formation in the APoE (apolipoprotein E) gene deficient mouse model when compared to conventional SPECT techniques. The pattern that was tested was a no-two-holes-touching (NTHT) modified uniformly redundant array (MURA) having 1,920 pinholes. The number of pinholes combined with the thin sintered tungsten plate was designed to increase the efficiency of the imaging modality over conventional gamma camera imaging methods while improving spatial resolution and reducing noise in the image reconstruction. The MDA required to image the vulnerable plaque in a human cardiac-torso mathematical phantom was simulated with a Monte Carlo code and evaluated to determine the optimum plate thickness by a receiver operating characteristic (ROC) yielding the lowest possible MDA and highest area under the curve (AUC). A partial 3D expectation maximization (EM) reconstruction was developed to improve signal-to-noise ratio (SNR), dynamic range, and spatial resolution over the linear correlation method of reconstruction. This improvement was evaluated by imaging a mini hot rod phantom, simulating the dynamic range, and by performing a bone scan of the C-57 control mouse. Results of the experimental and simulated data as well as other plate designs were analyzed for use as a small animal and potentially human cardiac imaging modality for a radiopharmaceutical developed at Bristol-Myers Squibb Medical Imaging Company, North Billerica, MA, for diagnosing vulnerable plaques. If left untreated, these plaques may rupture causing sudden, unexpected coronary occlusion and death. The results of this research indicated that imaging and reconstructing with this new partial 3D algorithm improved the SNR, spatial resolution, dynamic range of 4:1 to 6:1, and decreased the MDA required at the site of a plaque by twofold in comparison with other nuclear medicine imaging methods. Recommendations to increase the field of view (FOV) along with a better imaging geometry would enable placement of larger objects (human heart included) within the fully encoded FOV while improving spatial resolution, magnification factors, and efficiency. Further improvements to the algorithm and imaging system may enable novel vulnerable plaque imaging and early detection of coronary artery disease. 1See definitions beginning on page xvii.

  11. Evaluation of intralesional 5% 5-fluorouracil in resistant localized plaque psoriasis

    PubMed Central

    Mahajan, Bharat Bhushan; Singla, Monika

    2014-01-01

    Background: Psoriasis is a chronic, autoimmune, inflammatory papulosquamous disorder, the treatment of which remains challenging. A variety of therapeutic modalities have been used with varying degree of success. But, there is no such therapeutic modality till date that can prevent the relapse in psoriasis. Aims: The present study is being undertaken to evaluate the therapeutic efficacy of intralesional 5% 5-fluorouracil (5-FU) as well as its role in preventing relapse in resistant localized plaque psoriasis. Study Design: An open, prospective, randomized-controlled study. Materials and Methods: A total of 40 patients of resistant localized plaque psoriasis were enrolled for the study. Intralesional injection of 5% 5-FU was given in a dosage of 0.1 mL/cm2 of each plaque using an insulin syringe. In all patients, a single plaque was kept as control and was given intralesional injection of distilled water. A total of three injections were given in each plaque at weekly intervals. After that, patients were followed-up regularly at the interval of 2 weeks up to 12 weeks. All the lesions (both treated and control) were assessed clinically as well as photographically at each visit and graded using psoriasis severity index scoring. Results were analyzed statistically at the end of the follow-up period. Results: At 12 weeks follow-up, out of 40 patients treated, 4 (10%) patients had clearance (>90% resolution), 19 (47.5%) had excellent (70%-90%) improvement, whereas 12 (30%) patients were moderately (30%-70%) improved, and only 5 (12.5%) patients had mild or no improvement. Results were statistically significant in treated group in comparison to control group. Almost all patients complained of pain at the site of injection which subsided within 1-2 h. A total of 10 (25%) patients had necrosis after one or two injections which healed during the follow-up period within 6-8 weeks. Conclusion: Intralesional 5% 5-FU is found to be an effective therapeutic modality in resistant localized plaque psoriasis without much side effects. PMID:25165645

  12. Human APOE4 increases microglia reactivity at A? plaques in a mouse model of A? deposition

    PubMed Central

    2014-01-01

    Background Having the apolipoprotein E4 (APOE-?4) allele is the strongest genetic risk factor for the development of Alzheimer’s disease (AD). Accumulation of amyloid beta (A?) in the brain is influenced by APOE genotype. Transgenic mice co-expressing five familial AD mutations (5xFAD) in the presence of human APOE alleles (?2, ?3 or ?4) exhibit APOE genotype-specific differences in early A? accumulation, suggesting an interaction between APOE and AD pathology. Whether APOE genotype affects A?-plaque-associated neuroinflammation remains unclear. In the current study, we address the role of APOE genotype on A?-associated microglial reactivity in the EFAD transgenic mouse model. Methods We analyzed A?-induced glial activation in the brains of 6-month-old EFAD transgenic mice (E2FAD, E3FAD and E4FAD). Region-specific morphological profiles of A? plaques in EFAD brain sections were compared using immunofluorescence staining. We then determined the degree of glial activation in sites of A? deposition while comparing levels of the inflammatory cytokine Interleukin-1? (IL-1?) by ELISA. Finally, we quantified parameters of A?-associated microglial reactivity using double-stained EFAD brain sections. Results Characterization of A? plaques revealed there were larger and more intensely stained plaques in E4FAD mice relative to E2FAD and E3FAD mice. E4FAD mice also had a greater percentage of compact plaques in the subiculum than E3FAD mice. Reactive microglia and dystrophic astrocytes were prominent in EFAD brains, and primarily localized to two sites of significant A? deposition: the subiculum and deep layers of the cortex. Cortical levels of IL-1? were nearly twofold greater in E4FAD mice relative to E3FAD mice. To control for differences in levels of A? in the different EFAD mice, we analyzed the microglia within domains of specific A? deposits. Morphometric analyses revealed increased measures of microglial reactivity in E4FAD mice, including greater dystrophy, increased fluorescence intensity and a higher density of reactive cells surrounding cortical plaques, than in E3FAD mice. Conclusions In addition to altering morphological profiles of A? deposition, APOE genotype influences A?-induced glial activation in the adult EFAD cortex. These data support a role for APOE in modulating A?-induced neuroinflammatory responses in AD progression, and support the use of EFAD mice as a suitable model for mechanistic studies of A?-associated neuroinflammation. PMID:24948358

  13. ARTreat Project: three-dimensional numerical simulation of plaque formation and development in the arteries.

    PubMed

    Filipovic, Nenad; Rosic, Mirko; Tanaskovic, Irena; Milosevic, Zarko; Nikolic, Dalibor; Zdravkovic, Nebojsa; Peulic, Aleksandar; Kojic, Milos R; Fotiadis, Dimitris I; Parodi, Oberdan

    2012-03-01

    Atherosclerosis is a progressive disease characterized by the accumulation of lipids and fibrous elements in arteries. It is characterized by dysfunction of endothelium and vasculitis, and accumulation of lipid, cholesterol, and cell elements inside blood vessel wall. In this study, a continuum-based approach for plaque formation and development in 3-D is presented. The blood flow is simulated by the 3-D Navier-Stokes equations, together with the continuity equation while low-density lipoprotein (LDL) transport in lumen of the vessel is coupled with Kedem-Katchalsky equations. The inflammatory process was solved using three additional reaction-diffusion partial differential equations. Transport of labeled LDL was fitted with our experiment on the rabbit animal model. Matching with histological data for LDL localization was achieved. Also, 3-D model of the straight artery with initial mild constriction of 30% plaque for formation and development is presented. PMID:21937352

  14. Lifting the Silver Flakes: The Pathogenesis and Management of Chronic Plaque Psoriasis

    PubMed Central

    Chong, Heng T.; Cowin, Allison J.

    2013-01-01

    Psoriasis is a common chronic inflammatory skin condition in which patients suffer from mild to chronic plaque skin plaques. The disease manifests through an excessive inflammatory response in the skin due to complex interactions between different genetic and environmental factors. Psoriasis can affect the physical, emotional, and psychosocial well-being of patients, and currently there is no cure with treatments focusing primarily on the use of anti-inflammatory agents to control disease symptoms. Traditional anti-inflammatory agents can cause immunosuppression and adverse systemic effects. Further understanding of the disease has led to current areas of research aiming at the development of selective molecular targets to suppress the pathogenic immune responses. PMID:24062996

  15. Influence of electrode position on the characterization of artery stenotic plaques by using impedance catheter.

    PubMed

    Cho, Sungbo; Thielecke, Hagen

    2006-11-01

    Use of balloon impedance catheters (BIC) for the characterization of plaques in vessels can support an optimal medical treatment of plaques. The sensitivity of impedance diagnoses with BIC is related with the distribution of electric fields determined by the electrode configuration. Using the three-dimensional finite element method (FEM) simulation, it was estimated how the relative positions of electrode array to the lipid in the vessel affect on the total impedance magnitude. Further, the short-circuiting effect was investigated with respect to the separation distance on the angular axis between the electrode arrays of angular set. By aid of FEM simulations, it is possible to design the sets of multielectrode arrays which have an optimized resolution for individual vessels. PMID:17073347

  16. Psoriatic Plaques “Koebnerizing” to Areas of Acanthosis Nigricans in an Obese Female

    PubMed Central

    Deklotz, Cynthia M. C.; Eshagh, Karin

    2014-01-01

    Recent evidence suggests that the activation of several growth factor receptors (EGFR, IGFR1, and FGFRs) is a possible cause of acanthosis nigricans, a skin disorder characterized by velvety thin plaques in skin folds and often seen in patients with insulin resistance. The authors report a 14-year-old obese (body mass index = 38.5kg/m2) girl with a history of polycystic ovarian syndrome and pre-diabetes who presented with psoriatic plaques in her scalp and, subsequently, in areas mostly confined to where she had characteristic lesions of acanthosis nigricans. The authors propose that this as-of-yet unreported observation may represent a preferential koebnerization phenomenon where the abnormal keratinocyte proliferation in acanthosis nigricans may serve as the epidermal “micro-trauma” necessary to incite the prototypical isomorphic response seen in psoriasis. PMID:25489383

  17. Influence of plaque-forming bacterium, Rhodobacteraceae sp. on the growth of Chlorella vulgaris.

    PubMed

    Chen, Zhangran; Zhang, Jingyan; Lei, Xueqian; Zhang, Bangzhou; Cai, Guanjing; Zhang, Huajun; Li, Yi; Zheng, Wei; Tian, Yun; Xu, Hong; Zheng, Tianling

    2014-10-01

    Experiments were conducted to find out the molecular features, infection process of a special alga plaque-forming microorganism and its potential influence on the biomass of Chlorella vulgaris during the infection process. Direct contact between the algal cell and the bacterium may be the primary steps needed for the bacterium to lyse the alga. Addition of C. vulgaris cells into f/2 medium allowed us obtain the object bacterium. The 16S rRNA gene sequence comparisons results showed that the plaque-forming bacterium kept the closest relationship with Labrenzia aggregata IAM 12614(T) at 98.90%. The existence of the bacterium could influence both the dry weight and lipid content of C. vulgaris. This study demonstrated that direct cell wall disruption of C. vulgaris by the bacterium would be a potentially effective method to utilize the biomass of microalgae. PMID:25086475

  18. Dual-modality fiber-based OCT-TPL imaging system for simultaneous microstructural and molecular analysis of atherosclerotic plaques

    PubMed Central

    Wang, Tianyi; McElroy, Austin; Halaney, David; Vela, Deborah; Fung, Edmund; Hossain, Shafat; Phipps, Jennifer; Wang, Bingqing; Yin, Biwei; Feldman, Marc D.; Milner, Thomas E.

    2015-01-01

    New optical imaging techniques that provide contrast to study both the anatomy and composition of atherosclerotic plaques can be utilized to better understand the formation, progression and clinical complications of human coronary artery disease. We present a dual-modality fiber-based optical imaging system for simultaneous microstructural and molecular analysis of atherosclerotic plaques that combines optical coherence tomography (OCT) and two-photon luminescence (TPL) imaging. Experimental results from ex vivo human coronary arteries show that OCT and TPL optical contrast in recorded OCT-TPL images is complimentary and in agreement with histological analysis. Molecular composition (e.g., lipid and oxidized-LDL) detected by TPL imaging can be overlaid onto plaque microstructure depicted by OCT, providing new opportunities for atherosclerotic plaque identification and characterization. PMID:26137371

  19. Syrian Hamster model of postmenopausal hypercholesterolemia atherosclerosis and the development of plaques as imaged by high field MRI

    E-print Network

    McQuade, D. Tyler

    Syrian Hamster model of postmenopausal hypercholesterolemia atherosclerosis and the development of flaxseed in a hamster model of postmenopausal atherosclerosis. The focus is to examine in vivo identification of plaques in cerebral arteries and aortas of overiectomized (ovx) hamsters with endogenous

  20. Emergence in human dental plaque and host distribution of amylase-binding streptococci.

    PubMed

    Scannapieco, F A; Solomon, L; Wadenya, R O

    1994-10-01

    Salivary amylase is known to bind specifically to several species of oral streptococci. To assess the importance of this interaction in bacterial colonization of the oral cavity, we determined the proportion and identity of amylase-binding bacteria (ABB) in dental plaque of humans and various salivary amylase-secreting and non-secreting mammalian species. The numbers of ABB in undisturbed plaque collected over time from tooth surfaces of six human volunteers or from 14 other mammalian species were determined by means of a replicating assay. The mean proportion of ABB cultured aerobically from human teeth at 2 h was 10.5% (SD 10), at 8 h 7.9% (8), at 24 h 13% (11), and at 48 h 12% (9). The mean proportion of anaerobically cultured ABB found at 2 h was 3% (SD 4), at 8 h 5% (5), at 24 h 12% (9), and at 48 h 16% (12). Amylase-binding bacteria cultured from these samples resembled Streptococcus mitis, Streptococcus gordonii, Streptococcus salivarius, Streptococcus crista, or unidentified streptococci. In addition, only animals exhibiting salivary amylase activity in their saliva harbored ABB (ranging from 2 to 31% of the total flora), with the exception of the pig, where no ABB were found to colonize, despite considerable amylase activity in saliva. Only strains resembling S. mitis and S. salivarius and unspeciated strains were isolated from these mammals. These results suggest that amylase-binding streptococci are the predominant ABB in human plaque, and their numbers generally increase as plaque develops. Since ABB colonized only the oral cavities of hosts demonstrating salivary amylase activity, the ability to bind amylase may play an important role in oral colonization by these bacteria. PMID:7523468

  1. Using multimodal femtosecond CARS imaging to determine plaque burden in luminal atherosclerosis

    Microsoft Academic Search

    Alex C.-T. Ko; Leila B. Mostaço-Guidolin; Andrew Ridsdale; Adrian F. Pegoraro; Michael S. D. Smith; Aaron Slepkov; Mark D. Hewko; Elicia K. Kohlenberg; Bernie Schattka; Albert Stolow; Michael G. Sowa

    2011-01-01

    Luminal atherosclerosis imaging was demonstrated by multimodal femtosecond CARS microscopy (MM-CARS). Using a myocardial infarction-prone rabbit model of atherosclerosis, this study demonstrated the utility of multimodal CARS imaging in determining atherosclerotic plaque burden through two types of image analysis procedures. Firstly, multimodal CARS images were evaluated using a signal-intensity parameter based on intensity changes derived from the multi-channel data (e.g.

  2. Development of a plaque assay for Newcastle Disease virus. Memorandum report

    SciTech Connect

    Kournikakis, B.V.; Fildes, J.

    1987-02-01

    A reliable plaque assay system for virulent strains of Newcastle Disease virus (eg. Type BL, LaSota strain used in vaccines and at DRES as a viral BW simulant) utilizing a continuous monkey kidney cell line (LLC-MK2) is described. The use of a continuous cell line eliminates the added time and inconvenience of preparing primary cell cultures (eg. chick embryo fibroblasts) to quantitate the number of infectious virus particles.

  3. Classification of arterial plaque by spectral analysis of in vitro radio frequency intravascular ultrasound data

    Microsoft Academic Search

    Robin J. Watson; Calum C. McLean; M. Pauliina Moore; Timothy Spencer; Donald M. Salter; Tom Anderson; Keith A. A. Fox; W. Norman McDicken

    2000-01-01

    To test whether radio-frequency analysis of coronary plaques predicts the histological classification, r.f. data were collected using a 30 MHz intravascular ultrasound scanner. Two hundred ninety-nine regions-of-interest from eight postmortem coronary arteries were selected and identified by histology as falling into one of seven different tissue types. These are loose fibrous tissue (n = 78), moderate fibrous tissue (n =

  4. Dietary iron restriction increases plaque stability in apolipoprotein-E-deficient mice

    Microsoft Academic Search

    Hsueh-Te Lee; Li-Li Chiu; Tzong-Shyuan Lee; Hui-Ling Tsai; Lee-Young Chau

    2003-01-01

    Accumulative evidence has supported the role of iron in the development of atherosclerosis. To test whether iron-mediated oxidative stress influences plaque stability, apoliporotein-E (ApoE)-deficient mice (3 months old) were placed on a chow diet or a low-iron diet for 3 months, and the abundance of interstitial collagen and the expression of the matrix degradation-associated enzyme, matrix metalloproteinase-9 (MMP-9), in vascular

  5. Red and Black Rice Decrease Atherosclerotic Plaque Formation and Increase Antioxidant Status in Rabbits1

    Microsoft Academic Search

    Wen Hua Ling; Qi Xuan Cheng; Jing Ma; Tong Wang

    The influence of white, red and black rice consumption on atherosclerotic plaque formation induced by hypercholesterolemia was investigated in rabbits. Male rabbits (n 5 36) were divided into five groups. They were fed a normal laboratory purified diet (normal group, n 5 6), a high cholesterol (0.5g\\/100g) diet (HC group, n 5 6), a high cholesterol diet with 30 g\\/100

  6. Echogenic Carotid Plaques Are Associated With Aortic Arterial Stiffness in Subjects With Subclinical Carotid Atherosclerosis

    Microsoft Academic Search

    Mahmoud Zureik; Jeanne-Marie Bureau; Mohammed Temmar; Chris Adamopoulos; Dominique Courbon; Kathryn Bean; Pierre-Jean Touboul; Athanase Benetos; Pierre Ducimetière

    A better understanding of the interrelationships between the structure and function of the large arteries would lead to optimize cardiovascular disease prevention strategies. In this study, we investigated the relationships of aortic arterial stiffness assessed by carotid-femoral pulse-wave velocity (PWV), with carotid plaque echogenicity assessed by B-mode ultrasound. We analyzed 561 subjects (without coronary heart disease or stroke) who were

  7. Association Between Peak Expiratory Flow and the Development of Carotid Atherosclerotic Plaques

    Microsoft Academic Search

    Mahmoud Zureik; Francine Kauffmann; Pierre-Jean Touboul; Dominique Courbon; Pierre Ducimetiere

    2001-01-01

    Background: Numerous population-based studies have suggested that impaired lung function is associated with subsequent coronary heart diseases-related mortality and cardiovascular disease-related mortality. The relative con- tribution of atherosclerosis in these associations is un- known. Objective: To examine the association of peak expira- tory flow (PEF) with the occurrence during 4 years of atherosclerotic plaques in the extracranial carotid arter- ies

  8. Polymeric nanoparticle PET/MR imaging allows macrophage detection in atherosclerotic plaques

    PubMed Central

    Majmudar, Maulik D.; Yoo, Jeongsoo; Keliher, Edmund J.; Truelove, Jessica; Iwamoto, Yoshiko; Sena, Brena; Dutta, Partha; Borodovsky, Anna; Fitzgerald, Kevin; Di Carli, Marcelo; Libby, Peter; Anderson, Daniel G.; Swirski, Filip K.; Weissleder, Ralph; Nahrendorf, Matthias

    2013-01-01

    Rationale Myeloid cell content in atherosclerotic plaques associates with rupture and thrombosis. Thus, imaging of lesional monocyte and macrophages (Mo/M?) could serve as a biomarker of disease progression and therapeutic intervention. Objective To noninvasively assess plaque inflammation with dextran nanoparticle-facilitated hybrid PET/MR imaging. Methods and Results Using clinically approved building blocks, we systematically developed 13nm polymeric nanoparticles consisting of crosslinked short chain dextrans which were modified with desferoxamine for zirconium-89 radiolabeling (89Zr-DNP) and a near infrared fluorochrome (VT680) for microscopic and cellular validation. Flow cytometry of cells isolated from excised aortas showed DNP uptake predominantly in Mo/M? (76.7%) and lower signal originating from other leukocytes such as neutrophils and lymphocytes (11.8% and 0.7%, p<0.05 versus Mo/M?). DNP colocalized with the myeloid cell marker CD11b on immunohistochemistry. PET/MRI revealed high uptake of 89Zr-DNP in the aortic root of ApoE?/? mice (standard uptake value, ApoE?/? mice versus wild type controls, 1.9±0.28 versus 1.3±0.03, p<0.05), corroborated by ex vivo scintillation counting and autoradiography. Therapeutic silencing of the monocyte-recruiting receptor CCR2 with siRNA decreased 89Zr-DNP plaque signal (p<0.05) and inflammatory gene expression (p<0.05). Conclusions Hybrid PET/MR imaging with a 13nm DNP enables noninvasive assessment of inflammation in experimental atherosclerotic plaques and reports on therapeutic efficacy of anti-inflammatory therapy. PMID:23300273

  9. Prise en charge psychologique des personnes atteintes de sclérose en plaques

    Microsoft Academic Search

    A.-L. Ramelli

    2010-01-01

    Résumé  Connus dès la description initiale de la maladie, mais longtemps mésestimés, les troubles psychologiques chez les patients\\u000a atteints de sclérose en plaques (SEP) s’avèrent fréquents, hétérogènes et d’apparition précoce. Ils recouvrent des troubles\\u000a des fonctions cognitives (mémoire, attention, fonctions exécutives, vitesse de traitement de l’information), de l’humeur (dépression,\\u000a anxiété, euphorie) et des émotions (hyperexpressivité, rire et pleurs spasmodiques). Ils sont

  10. The effect of hexetidine mouthwash on the prevention of plaque and gingival inflammation: a systematic review

    Microsoft Academic Search

    F. Afennich; D. E. Slot; N. Hossainian; Weijden van der G. A

    2011-01-01

    To cite this article: Int J Dent Hygiene9, 2011; 182–190 DOI: 10.1111\\/j.1601-5037.2010.00478.x Afennich F, Slot DE, Hossainian N, Van der Weijden GA. The effect of hexetidine mouthwash on the prevention of plaque and gingival inflammation: a systematic review. Abstract: Objective: To review the literature concerning hexetidine-containing mouthwash as a monotherapy or as an adjunct to oral hygiene in the prevention

  11. [Comparative study on the efficacy of diflucortolone valerate in the psoriasis plaque test (author's transl)].

    PubMed

    Lofferer, O; Reckers, R

    1978-01-01

    Diflucortolone valerate was administered to 35 psoriatic patients of both sexes in 0.3% concentration as a W/O emulsion in comparison with various commercially available preparations to study its action in the psoriasis plaque test according to Scholtz and Dumas. The study showed the test substance to be equipotent with the halcinonide, clobetasol-17-propionate and desoximetasone preparations and significantly superior to those containing betamethasone-17,21-dipropionate, betamethasone-17-valerate and fluocinonide. PMID:373772

  12. Microglial cells and amyloid ? protein (A?) deposition: association with A? 40 -plaques

    Microsoft Academic Search

    D. M. A. Mann; T. Iwatsubo; H. Fukumoto; Y. Ihara; A. Odaka; N. Suzuki

    1995-01-01

    Two distinct species of amyloid protein (A) with different carboxyl termini, A40 and A42(43), are deposited in plaques in the brains of patients with Alzheimer's disease and Down's syndrome. The relationship between these two forms of A and microglial cells was investigated in 16 subjects with Down's syndrome ranging in age from 31 to 64 years. The amount of A40

  13. Curcumin inhibits formation of amyloid beta oligomers and fibrils, binds plaques, and reduces amyloid in vivo.

    PubMed

    Yang, Fusheng; Lim, Giselle P; Begum, Aynun N; Ubeda, Oliver J; Simmons, Mychica R; Ambegaokar, Surendra S; Chen, Pingping P; Kayed, Rakez; Glabe, Charles G; Frautschy, Sally A; Cole, Gregory M

    2005-02-18

    Alzheimer's disease (AD) involves amyloid beta (Abeta) accumulation, oxidative damage, and inflammation, and risk is reduced with increased antioxidant and anti-inflammatory consumption. The phenolic yellow curry pigment curcumin has potent anti-inflammatory and antioxidant activities and can suppress oxidative damage, inflammation, cognitive deficits, and amyloid accumulation. Since the molecular structure of curcumin suggested potential Abeta binding, we investigated whether its efficacy in AD models could be explained by effects on Abeta aggregation. Under aggregating conditions in vitro, curcumin inhibited aggregation (IC(50) = 0.8 microM) as well as disaggregated fibrillar Abeta40 (IC(50) = 1 microM), indicating favorable stoichiometry for inhibition. Curcumin was a better Abeta40 aggregation inhibitor than ibuprofen and naproxen, and prevented Abeta42 oligomer formation and toxicity between 0.1 and 1.0 microM. Under EM, curcumin decreased dose dependently Abeta fibril formation beginning with 0.125 microM. The effects of curcumin did not depend on Abeta sequence but on fibril-related conformation. AD and Tg2576 mice brain sections incubated with curcumin revealed preferential labeling of amyloid plaques. In vivo studies showed that curcumin injected peripherally into aged Tg mice crossed the blood-brain barrier and bound plaques. When fed to aged Tg2576 mice with advanced amyloid accumulation, curcumin labeled plaques and reduced amyloid levels and plaque burden. Hence, curcumin directly binds small beta-amyloid species to block aggregation and fibril formation in vitro and in vivo. These data suggest that low dose curcumin effectively disaggregates Abeta as well as prevents fibril and oligomer formation, supporting the rationale for curcumin use in clinical trials preventing or treating AD. PMID:15590663

  14. Association of Microglia with Amyloid Plaques in Brains of APP23 Transgenic Mice

    PubMed Central

    Stalder, Martina; Phinney, Amie; Probst, Alphonse; Sommer, Bernd; Staufenbiel, Matthias; Jucker, Mathias

    1999-01-01

    Microglia are a key component of the inflammatory response in the brain and are associated with senile plaques in Alzheimer’s disease (AD). Although there is evidence that microglial activation is important for the pathogenesis of AD, the role of microglia in cerebral amyloidosis remains obscure. The present study was undertaken to investigate the relationship between ?-amyloid deposition and microglia activation in APP23 transgenic mice which express human mutated amyloid-? precursor protein (?PP) under the control of a neuron-specific promoter element. Light microscopic analysis revealed that the majority of the amyloid plaques in neocortex and hippocampus of 14- to 18- month-old APP23 mice are congophilic and associated with clusters of hypertrophic microglia with intensely stained Mac-1- and phosphotyrosine-positive processes. No association of such activated microglia was observed with diffuse plaques. In young APP23 mice, early amyloid deposits were already of dense core nature and were associated with a strong microglial response. Ultrastructurally, bundles of amyloid fibrils, sometimes surrounded by an incomplete membrane, were observed within the microglial cytoplasm. However, microglia with the typical characteristics of phagocytosis were associated more frequently with dystrophic neurites than with amyloid fibrils. Although the present observations cannot unequivocally determine whether microglia are causal, contributory, or consequential to cerebral amyloidosis, our results suggest that microglia are involved in cerebral amyloidosis either by participating in the processing of neuron-derived ?PP into amyloid fibrils and/or by ingesting amyloid fibrils via an uncommon phagocytotic mechanism. In any case, our observations demonstrate that neuron-derived ?PP is sufficient to induce not only amyloid plaque formation but also amyloid-associated microglial activation similar to that reported in AD. Moreover, our results are consistent with the idea that microglia activation may be important for the amyloid-associated neuron loss previously reported in these mice. PMID:10362792

  15. Detection and Quantification of Calcified Coronary Plaque With Multidetector-Row CT

    Microsoft Academic Search

    J. Jeffrey Carr

    Multidetector-row computed tomography (MDCT) has rapidly developed into a powerful tool for noninvasive measurement of calcified\\u000a plaque in the coronary arteries over the past decade. Identification and quantification of coronary artery calcifications\\u000a (CAC) with X-ray devices is well established in the literature with chest radiographs, fluoroscopy, computed tomography (CT\\u000a without electrocardiogram [ECG] gating) and cardiac CT (electron beam CT [EBCT],

  16. Kalzifizierte Plaques der extrakraniellen hirnversorgenden Gefäße im Vergleich mit traditionellen Risikofaktoren als Prädiktor für relevante Koronararterienstenosen

    Microsoft Academic Search

    Jörg Nossen; Thomas Vierzigmann; Werner Weiß; Erich Lang

    2001-01-01

    Hintergrund: Neben den traditionellen atherogenen Risikofaktoren wurden wiederhold die Zusammenhänge zwischen sonographischen Läsionen der extrakraniellen hirnversorgenden Gefäße und relevanten Koronararterienstenosen untersucht, wobei meist die Intima-Media-Dicke Als Screening-Marker verwendet wurde. Ziel dieser Studie war die Evaluierung kalzifizierter Plaques der extrakraniellen Karotiden im Vergleich mit traditionellen Risikofaktoren als Prädiktor einer koronaren Herzkrankheit. Patienten und Methode: Bei 139 Patienten wurde sowohl eine B-Mode-Sonographie

  17. Ultrasound Assessment of Carotid Plaque Echogenicity Response to Statin Therapy: A Systematic Review and Meta-Analysis

    PubMed Central

    Ibrahimi, Pranvera; Jashari, Fisnik; Bajraktari, Gani; Wester, Per; Henein, Michael Y.

    2015-01-01

    Objective: To evaluate in a systematic review and meta-analysis model the effect of statin therapy on carotid plaque echogenicity assessed by ultrasound. Methods: We have systematically searched electronic databases (PubMed, MEDLINE, EMBASE and Cochrane Center Register) up to April, 2015, for studies evaluating the effect of statins on plaque echogenicity. Two researchers independently determined the eligibility of studies evaluating the effect of statin therapy on carotid plaque echogenicity that used ultrasound and grey scale median (GSM) or integrated back scatter (IBS). Results: Nine out of 580 identified studies including 566 patients’ carotid artery data were meta-analyzed for a mean follow up of 7.2 months. A consistent increase in the echogenicity of carotid artery plaques, after statin therapy, was reported. Pooled weighted mean difference % (WMD) on plaque echogenicity after statin therapy was 29% (95% CI 22%–36%), p < 0.001, I2 = 92.1%. In a meta-regression analysis using % mean changes of LDL, HDL and hsCRP as moderators, it was shown that the effects of statins on plaque echogenicity were related to changes in hsCRP, but not to LDL and HDL changes from the baseline. The effect of statins on the plaque was progressive; it showed significance after the first month of treatment, and the echogenicity continued to increase in the following six and 12 months. Conclusions: Statin therapy is associated with a favorable increase of carotid plaque echogenicity. This effect seems to be dependent on the period of treatment and hsCRP change from the baseline, independent of changes in LDL and HDL. PMID:25984600

  18. Nonalcoholic Hepatic Steatosis Is a Strong Predictor of High-Risk Coronary-Artery Plaques as Determined by Multidetector CT

    PubMed Central

    Osawa, Kazuhiro; Miyoshi, Toru; Yamauchi, Kentarou; Koyama, Yasushi; Nakamura, Kazufumi; Sato, Shuhei; Kanazawa, Susumu; Ito, Hiroshi

    2015-01-01

    Background Nonalcoholic fatty liver disease is associated with a risk of coronary artery disease (e.g., diabetes mellitus, dyslipidemia, metabolic syndrome). We evaluated whether nonalcoholic hepatic steatosis is associated with high-risk plaques as assessed by multidetector computed tomography (CT). Methods This retrospective study involved 414 participants suspected of having coronary artery disease. Nonalcoholic hepatic steatosis was defined as a liver-to-spleen fat ratio of <1.0 and the presence and appropriate characteristics of coronary-artery plaques as assessed by coronary CT angiography. High-risk plaques were identified, as were low-density plaques, positive remodeling, and spotty calcification. Results Compared with patients who did not have nonalcoholic hepatic steatosis, patients with nonalcoholic hepatic steatosis had more low-density plaques (21% vs. 44%, p<0.01), positive remodeling (41% vs. 58%, p = 0.01), and spotty calcification (12% vs. 36%, p<0.01). The number of high-risk plaques in patients with nonalcoholic hepatic steatosis was greater than in those without nonalcoholic hepatic steatosis (p<0.01). Patients with nonalcoholic hepatic steatosis were more likely to have high-risk plaques than were those with only an elevated level of visceral adipose tissue (?86 cm2; 35% vs. 16%, p<0.01). Multivariate analyses that included nonalcoholic hepatic steatosis, amount of visceral adipose tissue, and the presence/absence of traditional risk factors demonstrated that nonalcoholic hepatic steatosis was an independent predictor of high-risk plaques (odds ratio: 4.60; 95% confidence interval: 1.94–9.07, p<0.01). Conclusions Diagnosis of nonalcoholic hepatic steatosis may be of value when assessing the risk of coronary artery disease. PMID:26125952

  19. Diminished omega-3 fatty acids are associated with carotid plaques from neurologically symptomatic patients: Implications for carotid interventions

    Microsoft Academic Search

    Hernan A. Bazan; Yan Lu; Deepu Thoppil; Tamara N. Fitzgerald; Song Hong; Alan Dardik

    2009-01-01

    The omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are prevalent in fish oil and their cardioprotective effects are thought to be mediated by anti-inflammatory mechanisms. The aim of this study is to determine whether omega-3 fatty acids are associated with carotid plaques from neurologically symptomatic patients. Plaques were obtained from 41 patients (mean age 62 [44–84]; 24-asymptomatic,

  20. Mitochondrial Alterations near Amyloid Plaques in an Alzheimer's Disease Mouse Model

    PubMed Central

    Xie, Hong; Guan, JiSong; Borrelli, Laura A.; Xu, Jing; Serrano-Pozo, Alberto

    2013-01-01

    While accumulation of amyloid-? (A?) deposited as senile plaques is a hallmark feature of Alzheimer's disease (AD), the neurotoxicity of these deposits remains controversial. Recent in vitro studies suggested a link between elevated A? and mitochondrial dysfunction that might contribute to the pathogenesis of AD. However, the in vivo evidence for mitochondria dysfunction caused by A? is still missing. Using intravital multiphoton imaging with a range of fluorescent markers, we systematically surveyed mitochondrial structural and functional changes in AD mouse models. We observed severe impairments to be limited to the vicinity of A? plaques, which included reduction of both numbers and membrane potential of mitochondria and the emergence of dystrophic and fragmented mitochondria. Both neuronal soma and neurites with oxidative stress show severe alterations in mitochondrial membrane potential in amyloid precursor protein mice. These results provide in vivo evidence revealing A? plaques as focal sources of toxicity that lead to severe structural and functional abnormalities in mitochondria. These alterations may contribute to neuronal network dysfunction and warrant further investigation as possible targets for therapeutic intervention in AD. PMID:24155308

  1. Assessing atherosclerotic plaque morphology: comparison of optical coherence tomography and high frequency intravascular ultrasound.

    PubMed Central

    Brezinski, M. E.; Tearney, G. J.; Weissman, N. J.; Boppart, S. A.; Bouma, B. E.; Hee, M. R.; Weyman, A. E.; Swanson, E. A.; Southern, J. F.; Fujimoto, J. G.

    1997-01-01

    BACKGROUND: OCT can image plaque microstructure at a level of resolution not previously demonstrated with other imaging techniques because it uses infrared light rather than acoustic waves. OBJECTIVES: To compare optical coherence tomography (OCT) and intravascular ultrasound (IVUS) imaging of in vitro atherosclerotic plaques. METHODS: Segments of abdominal aorta were obtained immediately before postmortem examination. Images of 20 sites from five patients were acquired with OCT (operating at an optical wavelength of 1300 nm which was delivered to the sample through an optical fibre) and a 30 MHz ultrasonic transducer. After imaging, the microstructure of the tissue was assessed by routine histological processing. RESULTS: OCT yielded superior structural information in all plaques examined. The mean (SEM) axial resolution of OCT and IVUS imaging was 16 (1) and 110 (7), respectively, as determined by the point spread function from a mirror. Furthermore, the dynamic range of OCT was 109 dB compared with 43 dB for IVUS imaging. CONCLUSIONS: OCT represents a promising new technology for intracoronary imaging because of its high resolution, broad dynamic range, and ability to be delivered through intravascular catheters. Images PMID:9196405

  2. Impact of Wall Shear Stress and Pressure Variation on the Stability of Atherosclerotic Plaque

    NASA Astrophysics Data System (ADS)

    Taviani, V.; Li, Z. Y.; Sutcliffe, M.; Gillard, J.

    Rupture of vulnerable atheromatous plaque in the carotid and coronary arteries often leads to stroke and heart attack respectively. The mechanism of blood flow and plaque rupture in stenotic arteries is still not fully understood. A three dimensional rigid wall model was solved under steady and unsteady conditions assuming a time-varying inlet velocity profile to investigate the relative importance of axial forces and pressure drops in arteries with asymmetric stenosis. Flow-structure interactions were investigated for the same geometry and the results were compared with those retrieved with the corresponding one dimensional models. The Navier-Stokes equations were used as the governing equations for the fluid. The tube wall was assumed linearly elastic, homogeneous isotropic. The analysis showed that wall shear stress is small (less than 3.5%) with respect to pressure drop throughout the cycle even for severe stenosis. On the contrary, the three dimensional behavior of velocity, pressure and wall shear stress is in general very different from that predicted by one dimensional models. This suggests that the primary source of mistakes in one dimensional studies comes from neglecting the three dimensional geometry of the plaque. Neglecting axial forces only involves minor errors.

  3. Differential medium for detecting dental plaque bacteria resembling Actinomyces viscosus and Actinomyces naeslundii.

    PubMed

    Ellen, R P; Balcerzak-Raczkowski, I B

    1975-10-01

    A medium for detecting colonies of Actinomyces viscosus and Actinomyces naeslundii in dental plaque samples was developed. The medium (CNAC-20) contains 20.0 mug of 3CdSO4-8H2O per ml of Columbia CNA agar base. Laboratory strains of A. viscosus grew on CNAC-20 in characteristic round, white, smooth, opaque colonies. Increasing the cadmium concentration impaired the growth of some A. viscosus strains. Stock strains of A. naeslundii and A. israelii grew in colonies of similar white, opaque morphology. The few strains of other gram-positive plaque bacteria that grew on CNAC-20 had colonies easily distinguished from those of A. viscosus. Most of the bacterial strains freshly isolated from Actinomyces-like colonies on CNAC-20 that had been inoculated with human dental plaque samples were found to have cultural characteristics consistent with previous descriptions of A. viscosus or A. naeslundii. CNAC-20 may facilitate investigations into the relationship of microaerophilic Actinomyces with the etiology of dental diseases. PMID:1184734

  4. Neopterin is associated with plaque inflammation and destabilisation in human coronary atherosclerotic lesions

    PubMed Central

    Adachi, T; Naruko, T; Itoh, A; Komatsu, R; Abe, Y; Shirai, N; Yamashita, H; Ehara, S; Nakagawa, M; Kitabayashi, C; Ikura, Y; Ohsawa, M; Yoshiyama, M; Haze, K; Ueda, M

    2007-01-01

    Background Previous studies have shown that recent activation of the inflammatory response in coronary atherosclerotic lesions contributes to rapid progressive plaque destabilisation. Neopterin, a by?product of the guanosine triphosphate pathway, is produced by activated macrophages and serves as an activation marker for monocytes/macrophages. Objective To elucidate the role of neopterin in coronary plaque destabilisation by immunohistochemical study of the presence of neopterin in coronary atherectomy specimens obtained from patients with stable angina pectoris (SAP) and unstable angina pectoris (UAP). Patients and methods All patients underwent atherectomy of the primary atherosclerotic lesions responsible for SAP (n?=?25) and UAP (n?=?25). Frozen samples were studied with antibodies against smooth muscle cells, macrophages, T cells, neutrophils and neopterin. Results In 22/25 patients with UAP, abundant neopterin?positive macrophages were found at the sites of coronary culprit lesions. However, in 25 lesions from patients with SAP, only 11 lesions showed neopterin positivity. Quantitatively, the neopterin?positive macrophage score was significantly higher (p<0.001) in patients with UAP than in patients with SAP. Moreover, the neopterin?positive macrophage score showed a significant positive correlation with the number of neutrophils or T cells, respectively (neutrophils, r?=?0.55, p<0.001; T cells, r?=?0.70, p<0.001). Conclusions Neopterin can be considered as one of the significant factors in the process of plaque inflammation and destabilisation in human coronary atherosclerotic lesions. Its exact role in the process needs to be investigated further. PMID:17575334

  5. Establishment of treatment parameters for ALA-PDT of plaque psoriasis

    NASA Astrophysics Data System (ADS)

    Stringer, Mark R.; Robinson, Dominic J.; Collins, P.

    1996-12-01

    We report an investigation into the use of photodynamic therapy (PDT), following topically applied 5-aminolaevulinic acid (ALA), as a treatment for plaque psoriasis. Treatment was performed 4 hours post-ALA, using white light doses of 2 - 16 J cm-2 delivered at 10 - 40 mW cm-2. The fluorescence emission of protoporphyrin IX was used as an indicator of the relative concentration of photosensitizer within each plaque before, during, and after therapy. Results show that the rate of sensitizer photo- oxidation is proportional to both pre-treatment fluorescence intensity and surface irradiance, consistent with a rate- equation analysis. A correlation of fluorescence measurements with clinical response of plaques indicates that the effectiveness of PDT is dominated by the level of PpIX at the onset of treatment, and is much less dependent upon light dose. Using these findings we have established a PDT treatment protocol that involves the delivery of 8 J cm-2 of white light, at a rate of 15 mW cm-2. The possibility of ALA-PDT being established as the therapy of choice is discussed.

  6. Development of alkoxy styrylchromone derivatives for imaging of cerebral amyloid-? plaques with SPECT.

    PubMed

    Fuchigami, Takeshi; Ogawa, Ayaka; Yamashita, Yuki; Haratake, Mamoru; Watanabe, Hiroyuki; Ono, Masahiro; Kawasaki, Masao; Yoshida, Sakura; Nakayama, Morio

    2015-08-15

    We report here the development of radioiodinated styrylchromone derivatives with alkoxy groups as single photon emission computed tomography (SPECT) imaging probes for cerebral amyloid-? (A?) plaques. Among the derivatives, the methoxy derivative 14 and the dimethoxy derivative 15 displayed relatively high affinity for the A?(1-42) aggregates with Ki values of 22 and 46nM, respectively. Fluorescent imaging demonstrated that 14 and 15 clearly labeled thioflavin-S positive A? plaques in the brain sections of Tg2576 transgenic mice. In the in vivo studies, [(125)I]14 and [(125)I]15 showed high initial brain uptake expressed as the percentage of the injected dose per gram (2.25% and 2.49% ID/g at 2min, respectively) with favorable clearance (0.12% and 0.20% ID/g at 180min, respectively) from the brain tissue of normal mice. Furthermore, in vitro autoradiography confirmed that [(125)I]15 binds thioflavin-S positive regions in Tg2576 mouse brain sections. The derivative 15 may be a potential scaffold for the development of in vivo imaging probes targeting A? plaques in the brain. In particular, further structural modifications are required to improve the compounds binding affinity for A?. PMID:26073008

  7. Combined acoustic-photoacoustic and fluorescence imaging catheter for the detection of the atherosclerotic plaque

    NASA Astrophysics Data System (ADS)

    Abran, Maxime; Matteau-Pelletier, Carl; Zerouali-Boukhal, Karim; Tardif, Jean-Claude; Lesage, Frédéric

    2011-03-01

    In industrialized countries, cardiovascular diseases remain the main cause of mortality. The detection of atherosclerosis and its associated plaque using imaging techniques allows studying the efficacy of new drugs in vivo. Intravascular ultrasound (IVUS) imaging has been demonstrated to be a powerful tool to uncover structural information of atherosclerotic plaques. Recently, intravascular photoacoustic (IVPA) has been combined with IVUS imaging to add functional and/or molecular information. The IVPA/IVUS combination has been demonstrated in phantoms and ex vivo tissues to provide relevant information about the composition of the plaque, as well as its vulnerability. In this work, we extend previous work by developing a combined IVPA/IVUS system using a rotating ultrasound transducer in a catheter to which an optical fiber is attached. In addition, a third modality was included through fluorescence detection in the same fiber at a distinct wavelength from PA, opening the door to complementary information using fluorescence activatable probes. Cylindrical silicon phantoms with inclusions containing fluorophores or ink were used to validate the system. Bleaching of the fluorophore by the pulsed laser used for photoacoustic was quantified. IVUS images were obtained continuously and used to co-register photoacoustic and fluorescence signals.

  8. A rapid DNA probe test compared to culture methods for identification of subgingival plaque bacteria.

    PubMed

    Tsai, Ching Yin; Wolff, Larry F; Germaine, Greg; Hodges, Jim

    2003-01-01

    There has been a significant amount of interest in developing a more rapid and cost-effective test to identify bacterial pathogens in plaque. DNA probe technology may meet both these objectives, it is more rapid and cost-effective when compared to culture methods. The purpose of this study was to compare an automated DNA probe test with classical culture methods for identifying Bacteroides forsythus and Porphyromonas gingivalis in subgingival plaque of patients with adult periodontitis. Subgingival plaque samples were collected from sites with moderate to severe periodontitis and divided into two aliquots for analysis by either DNA probe or culture methods. When the DNA probe method was compared with the culture method (gold standard), the sensitivity and specificity for B. forsythus were 92.0% (SE = 3.4%) and 50.5% (SE = 7.8%), respectively; for P. gingivalis they were 52.2% (SE = 8.7%) and 74.7% (SE = 5.9%), respectively. Detection of B. forsythus and P. gingivalis by DNA probe correlated with probing depth (P = 0.01 for B. forsythus and P = 0.03 for P. gingivalis). It was concluded the DNA probe test was comparable to culture methods in detecting B. forsythus. In addition, when compared to the culture method, a better correlation was obtained with DNA probe detection of B. forsythus or P. gingivalis and clinical parameters. PMID:12702112

  9. “Neglected nipples”: acanthosis nigricans-like plaques caused by avoidance of nipple cleansing

    PubMed Central

    Kaminska-Winciorek, Grazyna; Wydmanski, Jerzy; Scope, Alon; Argenziano, Giuseppe; Zalaudek, Iris

    2014-01-01

    Background: Acanthosis nigricans (AN) develops sporadically or in association with obesity, insulin-resistance and dark pigmentary phenotype. Unusual clinical presentations of AN may be diagnostically vexing. Objectives: The aim of the report is to present unusual clinical and dermoscopic pictures of hyper-keratotic, brownish lesions of the nipples resembling acanthosis nigricans. Patients/Methods: Data including clinical and dermoscopic features of two patients with the “neglected nipples”: acanthosis nigricans-like (AN-like) hyperpigmented plaques caused by avoidance of nipple cleansing. Results: Beside the anamnestic clue, presentation of AN-like plaques in the “neglected nipples” is limited to the breasts, in the absence of involvement of other flexural sites classically affected by AN. Dermoscopy aids the exclusion of a tumor, as it reveals exclusively structureless, brown-gray-black hyperkeratosis in the absence of criteria associated with melanocytic or non-melanocytic skin neoplasms of the nipple. The “neglected breasts” are easily treated by keratolytic creams and hygiene. Conclusions: The “neglected nipples” condition, presenting as bilateral AN-like papules and plaques of the nipples, is due to avoidance of cleansing of the nipple area, resulting in accumulation of keratotic cellular debris. PMID:25126467

  10. Quantitative Analysis of Monocyte Subpopulations in Murine Atherosclerotic Plaques by Multiphoton Microscopy

    PubMed Central

    Haka, Abigail S.; Potteaux, Stephane; Fraser, Haley; Randolph, Gwendalyn J.; Maxfield, Frederick R.

    2012-01-01

    The progressive accumulation of monocyte-derived cells in the atherosclerotic plaque is a hallmark of atherosclerosis. However, it is now appreciated that monocytes represent a heterogeneous circulating population of cells that differ in functionality. New approaches are needed to investigate the role of monocyte subpopulations in atherosclerosis since a detailed understanding of their differential mobilization, recruitment, survival and emigration during atherogenesis is of particular importance for development of successful therapeutic strategies. We present a novel methodology for the in vivo examination of monocyte subpopulations in mouse models of atherosclerosis. This approach combines cellular labeling by fluorescent beads with multiphoton microscopy to visualize and monitor monocyte subpopulations in living animals. First, we show that multiphoton microscopy is an accurate and timesaving technique to analyze monocyte subpopulation trafficking and localization in plaques in excised tissues. Next, we demonstrate that multiphoton microscopy can be used to monitor monocyte subpopulation trafficking in atherosclerotic plaques in living animals. This novel methodology should have broad applications and facilitate new insights into the pathogenesis of atherosclerosis and other inflammatory diseases. PMID:23024767

  11. Reduction of dental plaque deposition in humans by oolong tea extract.

    PubMed

    Ooshima, T; Minami, T; Aono, W; Tamura, Y; Hamada, S

    1994-01-01

    The inhibitory effect of oolong tea extract (OTE) containing polymerized polyphenols on plaque deposition was examined in 35 human volunteers. Thirty-five human volunteers, aged 18-29 years, who received extensive oral prophylactic procedures were requested to refrain from all oral hygiene procedures for 4 days, and to rinse their mouth with 0.5 mg/ml OTE solution in 0.2% ethanol before and after every intake of food and before sleeping at night. No restriction regarding meals was given during the test period, except to refrain from teas or coffee. Plaque deposition was evaluated after disclosing the teeth with Erythrocin at the termination of this experiment. The study was repeated 1 week after the first trial, but only 0.2% ethanol without OTE was used for mouthrinsing in the second trial. OTE was found to significantly inhibit plaque deposition in volunteers, although mouthrinsing with OTE solution had no significant effect on the number of mutans streptococci in unstimulated whole saliva. PMID:8033186

  12. Detecting microcalcifications in atherosclerotic plaques by a simple trichromic staining method for epoxy embedded carotid endarterectomies.

    PubMed

    Relucenti, M; Heyn, R; Petruzziello, L; Pugliese, G; Taurino, M; Familiari, G

    2010-01-01

    Atherosclerotic plaques have a high probability of undergoing rapid progression to stenosis, becoming responsible of acute coronary syndrome or stroke. Microcalcifications may act as enhancers of atherosclerotic plaque vulnerability. Considering that calcifications with a diameter smaller than 10 mm in paraffin embedded tissue are rather difficult to detect, our aim was to analyze microcalcifications on semithin sections from epoxy resin embedded samples of carotid endarterectomies using an original trichromic stain (methylene blue--azur B--basic fuchsine--alizarin red). We have compared samples stained either with our method, methylene blue-azur B alone or with Von Kossa staining, and methylene blue-azur B -basic fuchsine alone or with Von Kossa staining. Our method resulted to be simple and fast (ca. 2 min), it gives a sharp general contrast for all structures and allows to easy identify collagen and elastin. In addition, gray-green colour associated to intracellular lipid droplets evidences foam cells, which are particularly abundant in endarterectomies samples. Mast cells and their metachromatic granules are also well recognized. Calcifications over 0,5 mm are clearly recognizable. In conclusion, microcalcifications are clearly distinguished from the extracellular matrix in spite of their reduced dimensions. Methylene blue--azur B--basic fuchsine--alizarin red method is easy to use, reproducible, and is particularly suitable for the identification of microcalcifications in the morphological analysis of atherosclerotic plaques. PMID:20819772

  13. Salt in the wound: 18F-fluoride positron emission tomography for identification of vulnerable coronary plaques

    PubMed Central

    Vesey, Alex T.; Joshi, Nik V.; Newby, David E.; Dweck, Marc R.

    2015-01-01

    Ischaemic vascular events occur in relation to an underlying vulnerable plaque. The pathological hallmarks of high-risk plaques are well described and include inflammation and microcalcification. To date, non-invasive imaging modalities have lacked the spatial resolution to detect these processes with the necessary precision to facilitate clinical utility. Positron emission tomography (PET) using targeted radiopharmaceuticals affords a highly sensitive tool for identifying features of interest and has been in use for several decades in oncological practice. Recent developments have created hybrid scanning platforms which add the detailed spatial resolution of computed tomography (CT) and, for the first time, made imaging of individual coronary plaques feasible. In this study we compared the utility of PET-CT using 18F-fluoride and 18F-fluorodeoxglucose (18F-FDG) to detect high-risk or ruptured atherosclerotic plaques in vivo. 18F-fluoride localized to culprit and vulnerable plaques as determined by a combination of invasive imaging and histological tissue examination. In contradistinction, 18F-FDG analysis was compromised by non-specific myocardial uptake that obscured the coronary arteries. We discuss the findings of this study, the limitations of the current approach of vulnerable plaque assessment and some on-going developments in cardiovascular imaging with 18F-fluoride. PMID:25984456

  14. Salt in the wound: (18)F-fluoride positron emission tomography for identification of vulnerable coronary plaques.

    PubMed

    Adamson, Philip D; Vesey, Alex T; Joshi, Nik V; Newby, David E; Dweck, Marc R

    2015-04-01

    Ischaemic vascular events occur in relation to an underlying vulnerable plaque. The pathological hallmarks of high-risk plaques are well described and include inflammation and microcalcification. To date, non-invasive imaging modalities have lacked the spatial resolution to detect these processes with the necessary precision to facilitate clinical utility. Positron emission tomography (PET) using targeted radiopharmaceuticals affords a highly sensitive tool for identifying features of interest and has been in use for several decades in oncological practice. Recent developments have created hybrid scanning platforms which add the detailed spatial resolution of computed tomography (CT) and, for the first time, made imaging of individual coronary plaques feasible. In this study we compared the utility of PET-CT using (18)F-fluoride and (18)F-fluorodeoxglucose ((18)F-FDG) to detect high-risk or ruptured atherosclerotic plaques in vivo. (18)F-fluoride localized to culprit and vulnerable plaques as determined by a combination of invasive imaging and histological tissue examination. In contradistinction, (18)F-FDG analysis was compromised by non-specific myocardial uptake that obscured the coronary arteries. We discuss the findings of this study, the limitations of the current approach of vulnerable plaque assessment and some on-going developments in cardiovascular imaging with (18)F-fluoride. PMID:25984456

  15. Real-time tissue elastography for the detection of vulnerable carotid plaques in patients undergoing endarterectomy: a pilot study.

    PubMed

    Liu, Fengju; Yong, Qiang; Zhang, Qinyi; Liu, Peng; Yang, Yuguang

    2015-03-01

    We examined the utility of ultrasonic real-time tissue elastography (RTE) and conventional B-mode ultrasound (US) in the detection of vulnerable carotid atherosclerotic plaques. This prospective study comprised 19 patients scheduled for carotid endarterectomy. Results obtained from pre-operative RTE and B-mode US and post-operative pathology were compared. RTE encoded low, average and high deformability as blue, green and red, respectively. Tissue hardness was scored on a 5-point scale, and relative strains were calculated. The relative strain was 1.12 ± 0.14 for fibrous plaques (n = 4), 0.28 ± 0.07 for atherosclerotic plaques (n = 5), 0.47 ± 0.31 for intraplaque hemorrhage/thrombosis (n = 5) and 0.98 ± 1.04 for complex plaques (n = 5). The sensitivity, specificity and accuracy of detection of vulnerable plaques were 25%, 100% and 84.2% for B-mode US, 50%, 100% and 89.4% for RTE and 62.5%, 100% and 94.7% for the combination. Ultrasonic RTE is a potential candidate for a non-invasive and effective approach to identify vulnerable atherosclerotic plaques in the carotid artery. PMID:25619789

  16. Angioscopic image-enhanced observation of atherosclerotic plaque phantom by near-infrared multispectral imaging at wavelengths around 1200 nm

    NASA Astrophysics Data System (ADS)

    Ishii, K.; Nagao, R.; Matsui, D.; Awazu, K.

    2015-02-01

    Spectroscopic techniques have been researched for intravascular diagnostic imaging of atherosclerotic plaque. Nearinfrared (NIR) light efficiently penetrates of biological tissues, and the NIR region contains the characteristic absorption range of lipid-rich plaques. The objective of this study is to observe atherosclerotic plaque using a NIR multispectral angioscopic imaging. Atherosclerotic plaque phantoms were prepared using a biological tissue model and bovine fat. For the study, we developed an NIR multispectral angioscopic imaging system with a halogen light, mercury-cadmiumtelluride camera, band-pass filters and an image fiber. Apparent spectral absorbance was obtained at three wavelengths, 1150, 1200 and 1300 nm. Multispectral images of the phantom were constructed using the spectral angle mapper algorithm. As a result, the lipid area, which was difficult to observe in a visible image, could be clearly observed in a multispectral image. Our results show that image-enhanced observation and quantification of atherosclerotic plaque by NIR multispectral imaging at wavelengths around 1200 nm is a promising angioscopic technique with the potential to identify lipid-rich plaques.

  17. Increased Platelet Reactivity Is Associated with Circulating Platelet-Monocyte Complexes and Macrophages in Human Atherosclerotic Plaques

    PubMed Central

    Vrijenhoek, Joyce E. P.; van Holten, Thijs C.; Elsenberg, Ellen H. A. M.; Mak-Nienhuis, Elske M.; de Borst, Gert Jan; Jukema, J. Wouter; Pijls, Nico H. J.; Waltenberger, Johannes; van Zonneveld, Anton Jan; Moll, Frans L.; McClellan, Elizabeth; Stubbs, Andrew; Pasterkamp, Gerard; Hoefer, Imo; de Groot, Philip G.; Roest, Mark

    2014-01-01

    Objective Platelet reactivity, platelet binding to monocytes and monocyte infiltration play a detrimental role in atherosclerotic plaque progression. We investigated whether platelet reactivity was associated with levels of circulating platelet-monocyte complexes (PMCs) and macrophages in human atherosclerotic carotid plaques. Methods Platelet reactivity was determined by measuring platelet P-selectin expression after platelet stimulation with increasing concentrations of adenosine diphosphate (ADP), in two independent cohorts: the Circulating Cells cohort (n?=?244) and the Athero-Express cohort (n?=?91). Levels of PMCs were assessed by flow cytometry in blood samples of patients who were scheduled for percutaneous coronary intervention (Circulating Cells cohort). Monocyte infiltration was semi-quantitatively determined by histological examination of atherosclerotic carotid plaques collected during carotid endarterectomy (Athero-Express cohort). Results We found increased platelet reactivity in patients with high PMCs as compared to patients with low PMCs (median (interquartile range): 4153 (1585–11267) area under the curve (AUC) vs. 9633 (3580–21565) AUC, P<0.001). Also, we observed increased platelet reactivity in patients with high macrophage levels in atherosclerotic plaques as compared to patients with low macrophage levels in atherosclerotic plaques (mean±SD; 8969±3485 AUC vs. 7020±3442 AUC, P?=?0.02). All associations remained significant after adjustment for age, sex and use of drugs against platelet activation. Conclusion Platelet reactivity towards ADP is associated with levels of PMCs and macrophages in human atherosclerotic carotid plaques. PMID:25122139

  18. Dendritic Spine Density, Morphology, and Fibrillar Actin Content Surrounding Amyloid-? Plaques in a Mouse Model of Amyloid-? Deposition

    PubMed Central

    Kirkwood, Caitlin M.; Ciuchta, Jennifer; Ikonomovic, Milos D.; Fish, Kenneth N.; Abrahamson, Eric E.; Murray, Patrick S.; Klunk, William E.; Sweet, Robert A.

    2013-01-01

    Dendritic spines are the site of the majority of excitatory synapses, the loss of which correlates with cognitive impairment in patients with Alzheimer disease. Substantial evidence indicates that amyloid-? (A?) peptide, either insoluble fibrillar A? deposited into plaques or soluble non-fibrillar A? species, can cause spine loss but the concurrent contributions of fibrillar A? and non-fibrillar A? to spine loss has not been previously assessed. We used multiple-label immunohistochemistry to measure spine density, size, and f-actin content surrounding plaques in the cerebral cortex in the PSAPP mouse model of A? deposition. Our approach allowed us to measure fibrillar A? plaque content and an index of non-fibrillar A? species concurrently. We found that spine density was reduced within 6 ?m of the plaque perimeter, remaining spines were more compact, and f-actin content per spine was increased. Measures of fibrillar A? plaque content were associated with reduced spine density near plaques, whereas measures of non-fibrillar A? species were associated with reduced spine density and size, but not altered f-actin content. These findings suggest that strategies to preserve dendritic spines in AD patients may need to address both non-fibrillar and fibrillar forms of A? and that non-fibrillar A? may exert spine toxicity through pathways not mediated by depolymerization of f-actin. PMID:23860033

  19. Existing plaques and neuritic abnormalities in APP:PS1 mice are not affected by administration of the gamma-secretase inhibitor LY-411575

    PubMed Central

    Garcia-Alloza, Monica; Subramanian, Meenakshi; Thyssen, Diana; Borrelli, Laura A; Fauq, Abdul; Das, Pritam; Golde, Todd E; Hyman, Bradley T; Bacskai, Brian J

    2009-01-01

    The ?-secretase complex is a major therapeutic target for the prevention and treatment of Alzheimer's disease. Previous studies have shown that treatment of young APP mice with specific inhibitors of ?-secretase prevented formation of new plaques. It has not yet been shown directly whether existing plaques would be affected by ?-secretase inhibitor treatment. Similarly, alterations in neuronal morphology in the immediate vicinity of plaques represent a plaque-specific neurotoxic effect. Reversal of these alterations is an important endpoint of successful therapy whether or not a treatment affects plaque size. In the present study we used longitudinal imaging in vivo with multiphoton microscopy to study the effects of the orally active ?-secretase inhibitor LY-411575 in 10–11 month old APP:PS1 mice with established amyloid pathology and neuritic abnormalities. Neurons expressed YFP allowing fluorescent detection of morphology whereas plaques were labelled with methoxy-XO4. The same identified neurites and plaques were followed in weekly imaging sessions in living mice treated daily (5 mg/kg) for 3 weeks with the compound. Although LY-411575 reduced A? levels in plasma and brain, it did not have an effect on the size of existing plaques. There was also no effect on the abnormal neuritic curvature near plaques, or the dystrophies in very close proximity to senile plaques. Our results suggest that therapeutics aimed at inhibition of A? generation are less effective for reversal of existing plaques than for prevention of new plaque formation and have no effect on the plaque-mediated neuritic abnormalities, at least under these conditions where A? production is suppressed but not completely blocked. Therefore, a combination therapy of A? suppression with agents that increase clearance of amyloid and/or prevent neurotoxicity might be needed for a more effective treatment in patients with pre-existing pathology. PMID:19419556

  20. Changes in dental plaque following hospitalisation in a critical care unit: an observational study

    PubMed Central

    2013-01-01

    Introduction Previous research has suggested that deterioration in oral health can occur following hospitalisation. The impact of such deterioration could increase the risk of oral disease, reduce quality of life and increase the potential for healthcare-associated infections (HCAI) such as healthcare-associated pneumonia (HAP). However, the strength of the evidence is limited by, amongst other factors, the few observational studies published that assess oral health longitudinally. In view of the microbiological component of oral diseases and HCAIs, the objective of this study was to investigate the microbiological changes in dental plaque following hospitalisation in a Critical Care Unit (CCU): (1) total number of cultivable bacteria and (2) presence and changes in specific HAP pathogens. Methods We conducted a prospective, longitudinal observational study in the CCU of University College Hospital, London. Study participants were recruited within 24 hours of admission. Dental plaque samples were collected from up to six sites per patient. The primary outcome was microbiological change from baseline to seven days with additional analysis for participants still present at day 14. Results 50 patients were recruited with 36 available for review at one week, with early discharge accounting for much of the loss to follow-up. The median total viable count of the plaque microbiota at baseline was 4.40 × 105 cfu/ml and increased at week one to 3.44 × 106 cfu/ml. The total viable microbe counts increased by a median of 2.26 × 106 cfu/ml from baseline to week one (95% CI: 3.19 × 106, 1.24 × 107) and this was statistically significant (P < 0.01). Specific HAP bacteria were detected in 26% of participants sampled, although accounted for a relatively low proportion of the total viable bacteria. Conclusion Total bacterial count of dental plaque increases during hospitalisation in CCU. This finding, together with the colonisation of dental plaque by HAP bacteria strengthens the evidence for a deterioration in oral health in CCU and a risk factor for negative health and quality of life outcomes. PMID:24007571

  1. Plaque removal efficacy of a new experimental battery-powered toothbrush relative to two advanced-design manual toothbrushes.

    PubMed

    Haun, Jan; Williams, Karen; Friesen, Lynn; Ferrante, Anita; Walters, Patricia A; Bartizek, Robert D; Biesbrock, Aaron R

    2002-01-01

    The current study was designed to assess the plaque removal efficacy of a novel experimental powered toothbrush (Crest SpinBrush Pro) compared to two leading manual toothbrushes, the Oral-B CrossAction and the Colgate Navigator. In addition, this paper reports the results of two additional studies examining the relative plaque removal efficacy of the two control manual toothbrushes and a number of other manual toothbrushes. The comparative study was a randomized, controlled, examiner-blind, nine-period crossover design, conducted among 127 adult subjects over a two-month period, that examined plaque removal with a new battery-powered toothbrush and two advanced-design manual toothbrushes. During the course of this study, subjects brushed three times with the experimental powered toothbrush and three times with each control manual toothbrush. Study participation was on a voluntary basis following written informed consent of the subjects. Plaque was scored before and after brushing using the Turesky, et al. Modification of the Quigley-Hein Index. Average baseline plaque scores were 2.68 to 2.69 for the three treatment groups. The experimental toothbrush delivered an adjusted (via analysis of covariance) mean difference between baseline and post-brushing plaque scores (i.e., a plaque removal score) of 0.69, while the control toothbrushes delivered adjusted mean differences of 0.46 (Colgate Navigator) and 0.54 (Oral-B CrossAction). All group differences were statistically significant (p < 0.001). The experimental powered toothbrush group had, on average, 49% and 28% greater plaque removal scores than the Colgate Navigator and Oral-B CrossAction groups, respectively. In addition, the Oral-B CrossAction group had, on average, a 16% greater plaque removal score than the Colgate Navigator group. This result was also statistically significant (p < 0.001). Results on buccal and lingual surfaces also demonstrated statistically significantly (p < 0.001) greater plaque removal for the experimental battery-powered toothbrush relative to the control manual toothbrushes. PMID:12518488

  2. Chlorhexidine alcohol base mouthrinse versus Chlorhexidine formaldehyde base mouthrinse efficacy on plaque control: Double blind, randomized clinical trials

    PubMed Central

    Lakhdar, Leila; Bouziane, Amal; Bensouda, Yahia; Abouqal, Redouane

    2013-01-01

    Background: Chlorhexidine is well known for its antiplaque effect. However, the mouthrinse based chlorhexidine antiplaque efficiency may vary according to the formulation of the final product. The aim of the present study was to compare anti-plaque effectiveness of two commercial mouthrinses: 0.12 % Chlorhexidine alcohol base (CLX-A) versus a diluted 0.1% Chlorhexidine non-alcohol base with 0.1% of Formaldehyde (CLX-F). Material and Methods: the study was a seven day randomized, double-blind, placebo-controlled trial including 30 volunteers. At the start, all participants received a dental prophylaxis. Over 7 days experimental non-brushing period, during which subjects abstained from all forms of mechanical oral hygiene, one group test rinsed twice daily with 15ml of an alcohol base 0.12% Chlorhexidine mouthrinse. The second group test used 15ml of alcohol free 0.1% Chlorhexidine mouthrinse base 0.1% formaldehyde twice daily. The negative control group used a placebo. Plaque indexes were recorded in all volunteers prior to treatment at Day 0, 1 and 7. Results: After 7 days, the mean plaque index for the first group was 0.76±0.38 compared with a mean plaque index of 1.43±0.56 for the second group. The difference in plaque scores between the groups was statistically significant. Conclusion: the results of this study showed that rinsing with an alcohol base 0.12% Chlorhexidine mouthrinse is significantly different from rinsing with an alcohol free 0.1% Chlorhexidine mouthrinse on plaque inhibition. Key words:Chlorhexidine, dental plaque, mouthrinse, alcohol, formaldehyde. PMID:23229237

  3. Wall motion in the stenotic carotid artery: association with greyscale plaque characteristics, the degree of stenosis and cerebrovascular symptoms

    PubMed Central

    2013-01-01

    Background Systolic dilation of the atherosclerotic carotid artery depends on several factors including arterial compliance and the haemodynamic environment. The purpose of this study was to quantify wall motion in stenotic carotid arteries and investigate any associations with the ultrasound greyscale plaque characteristics, the degree of stenosis, and the presence of cerebrovascular symptoms. Methods Variations in the lumen diameters of 61 stenotic carotid arteries (stenosis range 10%-95%) from 47 patients were measured before the proximal shoulder of the atherosclerotic plaque using ultrasound image sequences over several cardiac cycles. Absolute and percentage diameter changes from diastole to systole were calculated and their relationship to the degree of stenosis, greyscale plaque characteristics, and the presence of ipsilateral hemispheric symptoms were studied. Results The mean absolute diameter change from diastole to systole was 0.45 mm (s.d. 0.17), and the mean percentage diameter change was 6.9% (s.d. 3.1%). Absolute and percentage diameter changes did not have a statistically significant relationship to the degree of stenosis, greyscale plaque characteristics, or the presence of ipsilateral hemispheric symptoms (p?>?0.05). Parameters significantly correlated with the presence of symptoms were the degree of stenosis (p?=?0.01), plaque greyscale median (p?=?0.02) and the plaque surface irregularity index (p?=?0.02). Conclusions Our study confirmed the degree of stenosis, plaque greyscale median and our surface irregularity index were significant predictors of symptoms, but found no significant correlation between diameter changes of stenosed carotid arteries and the presence of ipsilateral hemispheric symptoms. PMID:24139162

  4. Relation of intima-media thickness to atherosclerotic plaques in carotid arteries. The Vascular Aging (EVA) Study.

    PubMed

    Bonithon-Kopp, C; Touboul, P J; Berr, C; Leroux, C; Mainard, F; Courbon, D; Ducimetière, P

    1996-02-01

    This study examined the relation between arterial wall thickness and local atherosclerosis in the carotid arteries (CAs) and their specific risk factors. B-mode ultrasonography of the CAs was performed in a cohort of 516 men and 756 women aged 59 to 71 years who had been recruited for the European Vascular Aging Study. Ultrasound examination included measurement of intima-media thickness of the common CA (CCA) and the sites of plaque in the internal CA and bifurcations. Significant associations between increases in CCA intima-media thickness and both the presence and severity of atherosclerotic plaque were found in men and women. Examination of specific risk factors for increases in CCA intima-media thickness in the presence of plaque showed that, after adjustment for sex, both ultrasound measurements were independently related to age, body mass index, hypertension, and ever smoking (versus never smoking). Diabetes and current smoking were associated with intima-media thickness only, whereas hypercholesterolemia was related to plaque only. However, when subjects who were taking lipid-lowering drugs were excluded, lipoproteins and apolipoproteins were more consistently related to intima-media thickness than to plaque. In subjects free from any antihypertensive treatment, both intima-media thickness and plaques were independently associated with systolic blood pressure. After adjustment for sex and other risk factors, the odds ratio for having at least one plaque associated with a 0.10-mm increase in CCA intima-media thickness was 1.18 (95% confidence interval, 1.05 to 1.32). In this relatively aged population, increases in intima-media thickness as measured in the CCAs were clearly related to locally detected atherosclerosis and known risk factors for atherosclerosis. Longitudinal studies are needed to clarify the role of arterial wall thickening in the atherosclerotic process. PMID:8620348

  5. Atherosclerotic Plaque Inflammation Varies Between Vascular Sites and Correlates With Response to Inhibition of Lipoprotein?Associated Phospholipase A2

    PubMed Central

    Fenning, Robert S.; Burgert, Mark E.; Hamamdzic, Damir; Peyster, Eliot G.; Mohler, Emile R.; Kangovi, Shreya; Jucker, Beat M.; Lenhard, Stephen C.; Macphee, Colin H.; Wilensky, Robert L.

    2015-01-01

    Background Despite systemic exposure to risk factors, the circulatory system develops varying patterns of atherosclerosis for unclear reasons. In a porcine model, we investigated the relationship between site?specific lesion development and inflammatory pathways involved in the coronary arteries (CORs) and distal abdominal aortas (AAs). Methods and Results Diabetes mellitus (DM) and hypercholesterolemia (HC) were induced in 37 pigs with 3 healthy controls. Site?specific plaque development was studied by comparing plaque severity, macrophage infiltration, and inflammatory gene expression between CORs and AAs of 17 DM/HC pigs. To assess the role of lipoprotein?associated phospholipase A2 (Lp?PLA2) in plaque development, 20 DM/HC pigs were treated with the Lp?PLA2 inhibitor darapladib and compared with the 17 DM/HC untreated pigs. DM/HC caused site?specific differences in plaque severity. In the AAs, normalized plaque area was 4.4?fold higher (P<0.001) and there were more fibroatheromas (9 of the 17 animals had a fibroatheroma in the AA and not the COR, P=0.004), while normalized macrophage staining area was 1.5?fold higher (P=0.011) compared with CORs. DM/HC caused differential expression of 8 of 87 atherosclerotic genes studied, including 3 important in inflammation with higher expression in the CORs. Darapladib?induced attenuation of normalized plaque area was site?specific, as CORs responded 2.9?fold more than AAs (P=0.045). Conclusions While plaque severity was worse in the AAs, inflammatory genes and inflammatory pathways that use Lp?PLA2 were more important in the CORs. Our results suggest fundamental differences in inflammation between vascular sites, an important finding for the development of novel anti?inflammatory therapeutics. PMID:25672369

  6. Cholesterol Diet Withdrawal Leads to an Initial Plaque Instability and Subsequent Regression of Accelerated Iliac Artery Atherosclerosis in Rabbits

    PubMed Central

    Khanna, Vivek; Jain, Manish; Singh, Vishal; Kanshana, Jitendra S.; Prakash, Prem; Barthwal, Manoj K.; Murthy, Puvvada S. R.; Dikshit, Madhu

    2013-01-01

    Effect of long term cholesterol diet withdrawal on accelerated atherosclerosis in iliac artery of New Zealand White (NZW) rabbits has not been explored so far. Atherosclerosis was thus induced in rabbits by a combination of balloon injury and atherogenic diet (AD) (1% cholesterol and 6% peanut oil) feeding for 8 weeks (baseline) followed by chow diet (CD) feeding for 4, 8, 16, 32, 50 and 64 weeks. The plaque characterization was done using histology, real time RT-PCR and vasoreactivity studies. Significant elevation in plasma lipids with AD feeding was normalized following 16 weeks of CD feeding. However, baseline comparison showed advanced plaque features even after 8 weeks of CD period with significant elevation in intima/media thickness ratio and plaque area later showing reduction at 50 and 64 weeks CD periods. Lesion lipid accumulation and CD68 positivity was maintained till 16 weeks of CD feeding which significantly reduced from 32 to 64 weeks CD periods. Baseline comparison showed significant increase in ground substance, MMP-9 and significant decrease in ?-actin and collagen content at 8 weeks CD period indicating features of unstable plaque. These features regressed up to 64 weeks of CD. Partial restoration of functional vasoconstriction and vasorelaxation was seen after 64 weeks of CD feeding. mRNA expression of MCP-1, VCAM-1, collagen type I and III, MMP-9, TIMP-1, IFN-?, TNF-?, IL-10 and eNOS supported the above findings. The study thus reveals insights into initial plaque instability and subsequent regression on AD withdrawal in this model. These results are suggestive of an appropriate window for drug intervention for plaque stability/regression and restenosis as well as improves understanding of plaque regression phenomenon in this model. PMID:24146955

  7. Automated Tracing of the Adventitial Contour of Aortoiliac and Peripheral Arterial Walls in CT Angiography (CTA) to Allow Calculation of Non-calcified Plaque Burden

    Microsoft Academic Search

    Bhargav Raman; Raghav Raman; Geoffrey D. Rubin; Sandy Napel

    Aortoiliac and lower extremity arterial atherosclerotic plaque burden is a risk factor for the development of visceral and\\u000a peripheral ischemic and aneurismal vascular disease. While prior research allows automated quantification of calcified plaque\\u000a in these body regions using CT angiograms, no automated method exists to quantify soft plaque. We developed an automatic algorithm\\u000a that defines the outer wall contour and

  8. Size of emptied plaque cavity following spontaneous rupture is related to coronary dimensions, not to the degree of lumen narrowing. A study with intravascular ultrasound in vivo

    PubMed Central

    von Birgelen, C; Klinkhart, W; Mintz, G; Wieneke, H; Baumgart, D; Haude, M; Bartel, T; Sack, S; Ge, J; Erbel, R

    2000-01-01

    OBJECTIVE—To identify any potential relations between the size of an emptied plaque cavity and the remodelling pattern, plaque or vessel dimensions, lumen narrowing, and other ultrasonic lesion characteristics.?DESIGN—Intravascular ultrasound was used to examine prospectively 51 ruptured ulcerated coronary plaques. Cross sectional area measurements comprised lumen, vessel, plaque, and emptied plaque cavity. Lumen narrowing was calculated as 1 ? (lesion lumen area/reference lumen area) × 100%. A remodelling index was calculated as lesion vessel area/reference vessel area, and plaques were divided into those with values > 1.05 (group A) and ? 1.05 (group B).?RESULTS—Of the total of 51 plaques, 36 (71%) were assigned to group A and 15 (29%) to group B. In neither group was there a significant difference in reference dimensions and lumen narrowing. However, lesion vessel (mean (SD): 22.6 (8.1) mm2 v 17.5 (4.3) mm2; p = 0.006) and plaque areas (15.8 (6.2) mm2 v 12.8 (3.2) mm2; p = 0.03) were greater in group A than in group B. The cavity inside the plaque was larger in group A than in group B (2.8 (1.6) mm2 v 1.8 (0.9) mm2; p = 0.007) and showed a positive linear relation with lesion and reference vessel size (r = 0.58 and 0.56, respectively; p < 0.001), but not with lumen narrowing.?CONCLUSIONS—The size of the emptied cavity inside ruptured plaques is on average larger in lesions with adaptive vascular remodelling, and shows a linear relation with lesion plaque and vessel size and with the reference dimensions, but not with the degree of lumen narrowing.???Keywords: intravascular ultrasound; ultrasonic scanning; plaque rupture; remodelling PMID:11040004

  9. Evaluation of multicontrast MRI including fat suppression and inversion recovery spin echo for identification of intra-plaque hemorrhage and lipid core in human carotid plaque using the mahalanobis distance measure.

    PubMed

    te Boekhorst, Bernard C; van 't Klooster, Ronald; Bovens, Sandra M; van de Kolk, Kees W; Cramer, Maarten J; van Oosterhout, Matthijs F; Doevendans, Pieter A; van der Geest, Rob J; Pasterkamp, Gerard; van Echteld, Cees J

    2012-06-01

    Intra-plaque hemorrhage (IPH) and lipid core, characteristics of rupture prone carotid plaques, are often visualized in vivo with MRI using T1 weighted gradient and spin echo, respectively. Increasing magnetic field strength may help to identify IPH and lipid core better. As a proof of concept, automatic segmentation of plaque components was performed with the Mahalanobis distance (MD) measure derived from image contrast from multicontrast MR images including inversion recovery spin echo and T1 weighted gradient echo with fat suppression. After MRI of nine formaldehyde-fixated autopsy specimens, the MDs and Euclidean Distances between plaque component intensities were calculated for each MR weighting. The distances from the carotid bifurcation and the size and shape of calcification spots were used as landmarks for coregistration of MRI and histology. MD between collagen/cell-rich area and IPH was largest with inversion recovery spin echo (4.2/9.3, respectively), between collagen/cell-rich area/foam cells and lipid core with T1 weighted gradient echo with fat suppression (26.9/38.2/4.6, respectively). The accuracy of detection of IPH, cell-rich area, and collagen increased when the MD classifier was used compared with the Euclidean Distance classifier. The enhanced conspicuity of lipid core and IPH in human carotid artery plaque, using ex vivo T1 weighted gradient echo with fat suppression and inversion recovery spin echo MRI and MD classifiers, demands further in vivo evaluation in patients. PMID:21997890

  10. Effects of intima stiffness and plaque morphology on peak cap stress

    PubMed Central

    2011-01-01

    Background Rupture of the cap of a vulnerable plaque present in a coronary vessel may cause myocardial infarction and death. Cap rupture occurs when the peak cap stress exceeds the cap strength. The mechanical stress within a cap depends on the plaque morphology and the material characteristics of the plaque components. A parametric study was conducted to assess the effect of intima stiffness and plaque morphology on peak cap stress. Methods Models with idealized geometries based on histology images of human coronary arteries were generated by varying geometric plaque features. The constructed multi-layer models contained adventitia, media, intima, and necrotic core sections. For adventitia and media layers, anisotropic hyperelastic material models were used. For necrotic core and intima sections, isotropic hyperelastic material models were employed. Three different intima stiffness values were used to cover the wide range reported in literature. According to the intima stiffness, the models were classified as stiff, intermediate and soft intima models. Finite element method was used to compute peak cap stress. Results The intima stiffness was an essential determinant of cap stresses. The computed peak cap stresses for the soft intima models were much lower than for stiff and intermediate intima models. Intima stiffness also affected the influence of morphological parameters on cap stresses. For the stiff and intermediate intima models, the cap thickness and necrotic core thickness were the most important determinants of cap stresses. The peak cap stress increased three-fold when the cap thickness was reduced from 0.25 mm to 0.05 mm for both stiff and intermediate intima models. Doubling the thickness of the necrotic core elevated the peak cap stress by 60% for the stiff intima models and by 90% for the intermediate intima models. Two-fold increase in the intima thickness behind the necrotic core reduced the peak cap stress by approximately 25% for both intima models. For the soft intima models, cap thickness was less critical and changed the peak cap stress by 55%. However, the necrotic core thickness was more influential and changed the peak cap stress by 100%. The necrotic core angle emerged as a critical determinant of cap stresses where a larger angle lowered the cap stresses. Contrary to the stiff and intermediate intima models, a thicker intima behind the necrotic core increased the peak cap stress by approximately 25% for the soft intima models. Adventitia thickness and local media regression had limited effects for all three intima models. Conclusions For the stiff and intermediate intima models, the cap thickness was the most important morphological risk factor. However for soft intima models, the necrotic core thickness and necrotic core angle had a bigger impact on the peak cap stress. We therefore need to enhance our knowledge of intima material properties if we want to derive critical morphological plaque features for risk evaluation. PMID:21477277

  11. Morphologically distinct types of amyloid plaques point the way to a better understanding of Alzheimer's disease pathogenesis.

    PubMed

    D'Andrea, M R; Nagele, R G

    2010-04-01

    The details of the sequence of pathological events leading to neuron death in Alzheimer's disease (AD) are not known. Even the formation of amyloid plaques, one of the major histopathological hallmarks of AD, is not clearly understood; both the origin of the amyloid and the means of its deposition remain unclear. It is still widely considered, however, that amyloid plaques undergo gradual growth in the interstitial space of the brain via continual extracellular deposition of amyloid beta peptides at "seeding sites," and that these growing plaques encroach progressively on neurons and their axons and dendritic processes, eventually leading to neuronal death. Actually, histopathological evidence to support this mechanism is sparse and of uncertain validity. The fact that the amyloid deposits in AD brains that are collectively referred to as plaques are of multiple types and that each seems to have a different origin often is overlooked. We have shown experimentally that many of the so-called "diffuse amyloid plaques," which lack associated inflammatory cells, are either the result of leaks of amyloid from blood vessels at focal sites of blood-brain barrier breaches or are artifacts resulting from grazing sections through the margins of dense core plaques. In addition, we have provided experimental evidence that neuronal death via necrosis leaves a residue that takes the form of a spheroid "cloud" of amyloid, released by cell lysis, surrounding a dense core that often contains neuronal nuclear material. Support for a neuronal origin for these "dense core amyloid plaques" includes their ability to attract inflammatory cells (microglia and immigrant macrophages) and that they contain nuclear and cytoplasmic components that are somewhat resistant to proteolysis by lysosomes released during neuronal cell lysis. We discuss here the clinical and therapeutic importance of recognizing that amyloid deposition occurs both within neurons (intracellular) and in the interstitial (extracellular) space of the brain. For dense core plaques, we propose that the latter location largely follows from the former. This scenario suggests that blocking intraneuronal amyloid deposition should be a primary therapeutic target. This strategy also would be effective for blocking the gradual compromise of neuronal function resulting from this intraneuronal deposition, and the eventual death and lysis of these amyloid-burdened neurons that leads to amyloid release and the appearance of dense core amyloid plaques in the interstitium of AD brains. PMID:20121465

  12. Influence of plaque morphology on the mechanism of luminal enlargement after directional coronary atherectomy and balloon angioplasty.

    PubMed Central

    Marsico, F.; Kubica, J.; De Servi, S.; Angoli, L.; Bramucci, E.; Costante, A. M.; Specchia, G.

    1995-01-01

    OBJECTIVE--To relate the mechanism of luminal gain after directional atherectomy and balloon angioplasty to the morphological characteristics of the coronary lesions, assessed by intravascular ultrasound imaging. DESIGN--Intravascular ultrasound imaging was performed before and after the revascularisation procedure to assess the contribution of wall stretching and plaque reduction in luminal gain. SUBJECTS--32 patients undergoing balloon angioplasty and 29 undergoing directional coronary atherectomy. MAIN RESULTS--The main luminal area in vessels treated by balloon angioplasty increased from 1.51 (SD 0.30) to 3.91 (1.09) mm2 (P < 0.0001) with a concomitant increase in total vessel area from 11.44 (2.73) to 13.07 (2.83) mm2 (P < 0.0001). Therefore stretching of the vessel wall accounted for 68% of the luminal gain while plaque reduction accounted for the remaining 32%. This mechanism ranged from 45% in non-calcific plaques to 81% in echogenic plaques. The main luminal area in vessels treated by directional atherectomy increased from 1.49 (0.32) to 4.68 (1.73) mm2 (P < 0.0001), with a concomitant increase of total vessel area from 13.61 (4.67) to 15.2 (4.04) mm2 (P = 0.006). Thus stretching of the vessel wall accounted for 49% of the luminal area gain and plaque reduction for the remaining 51%. The presence of calcium influenced the relative contribution of these two mechanisms to the final luminal gain after directional atherectomy, since in calcific plaques stretching of the vessel wall accounted for only 9% of the luminal gain as compared to 56% in non-calcific plaques. After balloon angioplasty there was greater evidence of coronary dissections (32% v 3% after directional atherectomy, P < 0.01) and plaque fissure (60% v 0%, P < 0.01). Plaque fissure was more frequently seen in echolucent and concentric lesions, whereas dissections prevailed in echogenic and eccentric lesions. CONCLUSIONS--Intravascular ultrasound imaging may allow the assessment of acute changes in lumen and vessel wall after revascularisation procedures, and help in evaluating the potential effect of the structure and morphology of coronary lesions on the mechanism of luminal enlargement. Images PMID:7546991

  13. Differential Inhibition of Human Atherosclerotic Plaque–Induced Platelet Activation by Dimeric GPVI-Fc and Anti-GPVI Antibodies

    PubMed Central

    Jamasbi, Janina; Megens, Remco T.A.; Bianchini, Mariaelvy; Münch, Götz; Ungerer, Martin; Faussner, Alexander; Sherman, Shachar; Walker, Adam; Goyal, Pankaj; Jung, Stephanie; Brandl, Richard; Weber, Christian; Lorenz, Reinhard; Farndale, Richard; Elia, Natalie; Siess, Wolfgang

    2015-01-01

    Background Glycoprotein VI (GPVI) is the essential platelet collagen receptor in atherothrombosis, but its inhibition causes only a mild bleeding tendency. Thus, targeting this receptor has selective antithrombotic potential. Objectives This study sought to compare compounds interfering with platelet GPVI–atherosclerotic plaque interaction to improve current antiatherothrombotic therapy. Methods Human atherosclerotic plaque–induced platelet aggregation was measured in anticoagulated blood under static and arterial flow conditions (550/s, 1,100/s, and 1,500/s). Inhibition by dimeric GPVI fragment crystallizable region of IgG (Fc) masking GPVI binding sites on collagen was compared with that of 3 anti-GPVI antibodies: BLO8-1, a human domain antibody; 5C4, a fragment antigen-binding (Fab fragment) of monoclonal rat immunoglobulin G; and m-Fab-F, a human recombinant sFab against GPVI dimers. Results GPVI-Fc reduced plaque-triggered platelet aggregation in static blood by 51%, BLO8-1 by 88%, and 5C4 by 93%. Under arterial flow conditions, BLO8-1 and 5C4 almost completely inhibited platelet aggregation while preserving platelet adhesion on plaque. Inhibition by GPVI-Fc, even at high concentrations, was less marked but increased with shear rate. Advanced optical imaging revealed rapid persistent GPVI-Fc binding to collagen under low and high shear flow, upstream and downstream of plaque fragments. At low shear particularly, platelets adhered in plaque flow niches to GPVI-Fc–free segments of collagen fibers and recruited other platelets onto aggregates via ADP and TxA2 release. Conclusions Anti-GPVI antibodies inhibit atherosclerotic plaque-induced platelet aggregation under static and flow conditions more effectively than GPVI-Fc. However, potent platelet inhibition by GPVI-Fc at a higher shear rate (1,500/s) suggests localized antithrombotic efficacy at denuded or fissured stenotic high-risk lesions without systemic bleeding. The compound-specific differences have relevance for clinical trials targeting GPVI-collagen interaction combined with established antiplatelet therapies in patients with spontaneous plaque rupture or intervention-associated plaque injury. PMID:26046734

  14. Segmentation of Carotid Plaque using Multi-Contrast 3D Gradient Echo MR Imaging

    PubMed Central

    Liu, Wenbo; Balu, Niranjan; Sun, Jie; Zhao, Xihai; Chen, Huijun; Yuan, Chun; Zhao, Huilin; Xu, Jianrong; Wang, Guangzhi; Kerwin, William S.

    2011-01-01

    Purpose To evaluate the performance of automatic segmentation of atherosclerotic plaque components using solely multi-contrast 3D gradient echo (GRE) MR imaging. Materials and Methods A total of 15 patients with a history of recent transient ischemic attacks or stroke underwent carotid vessel wall imaging bilaterally with a combination of 2D turbo spin echo (TSE) sequences and 3D gradient echo (GRE) sequences. The TSE sequences included T1-weighted, T2-weighted, and contrast-enhanced T1-weighted scans. The 3D GRE sequences included time-of-flight (TOF), magnetization-prepared rapid gradient echo (MP-RAGE), and motion-sensitized driven equilibrium prepared rapid gradient echo (MERGE) scans. From these images, the previously developed morphology-enhanced probabilistic plaque segmentation (MEPPS) algorithm was retrained based solely on the 3D GRE sequences to segment necrotic core (NC), calcification (CA) and loose matrix (LM). Segmentation performance was assessed using a leave-one-out cross-validation approach via comparing the new 3D-MEPPS algorithm to the original MEPPS algorithm that was based on the traditional multi-contrast protocol including 2D TSE and TOF sequences. Results Twenty arteries of 15 subjects were found to exhibit significant plaques within the coverage of all imaging sequences. For these arteries, between new and original MEPPS algorithms, the areas per slice exhibited correlation coefficients of 0.86 for NC, 0.99 for CA and 0.80 for LM; no significant area bias was observed. Conclusion The combination of 3D imaging sequences (TOF, MP-RAGE and MERGE) can provide sufficient contrast to distinguish NC, CA and LM. Automatic segmentation using 3D sequences and traditional multi-contrast protocol produced highly similar results. PMID:22127812

  15. Active proliferation of different cell types, including lymphocytes, in human atherosclerotic plaques.

    PubMed Central

    Rekhter, M. D.; Gordon, D.

    1995-01-01

    Cell proliferation, an important mechanism of atherosclerotic plaque growth, occurs among smooth muscle, inflammatory cell, and other cell types. We have identified different topographical patterns of cell proliferation in human carotid plaques, based on cell type. Cell proliferation was determined with an antibody to the proliferating cell nuclear antigen (PCNA), combined with cell type-specific antibodies. Despite low levels of overall proliferative activity, the intima displayed more proliferative activity than the underlying media (1.61 +/- 0.35% in intima versus 0.05 +/- 0.03% in media; P < 0.01). The preponderant proliferative cell type in the intima was the monocyte/macrophage (46.0% of PCNA-positive cells), with a minority being smooth muscle alpha-actin-positive (9.7%), microvascular endothelial (14.3%), and T cells (13.1%). Smooth muscle cells were the dominant proliferating cell type in the media (44.4% of PCNA-positive cells versus 20% endothelial cells, 13.0% monocyte/macrophages, and 14.3% T cells). Within the plaque, foam-cell-rich regions mostly displayed proliferation among macrophages (66.5%), whereas in vascularized fields PCNA positivity was almost equally shared by endothelial cells (23.8%), monocyte/macrophages (26.3%), smooth muscle alpha-actin-positive cells (14.0%), and to a lesser extent, T cells (8.2%). Logistic and linear regression analyses also demonstrated that location in foam-cell-rich regions was a significant predictor of proliferation only among monocyte/macrophages, whereas location in vascularized regions was a good predictor of PCNA positivity among both inflammatory and noninflammatory cells. These different patterns of cell type proliferation suggest possibly different distributions of putative responsible growth regulatory factors in human atherosclerosis. Images Figure 1 Figure 2 PMID:7677178

  16. Endoscopic fluorescence lifetime imaging microscopy (FLIM) images of aortic plaque: an automated classification method

    NASA Astrophysics Data System (ADS)

    Phipps, Jennifer; Sun, Yinghua; Hatami, Nisa; Fishbein, Michael C.; Rajaram, Amit; Saroufeem, Ramez; Marcu, Laura

    2010-02-01

    The objective of this study was to develop an automated algorithm which uses fluorescence lifetime imaging microscopy (FLIM) images of human aortic atherosclerotic plaque to provide quantitative and spatial information regarding compositional features related to plaque vulnerability such as collagen degradation, lipid accumulation, and macrophage infiltration. Images were acquired through a flexible fiber imaging bundle with intravascular potential at two wavelength bands optimal to recognizing markers of vulnerability: F377: 377/55 nm and F460: 460/50 nm (center wavelength/bandwidth). A classification method implementing principal components analysis and linear discriminant analysis to correlate FLIM data sets with histopathology was validated on a training set and then used to classify a validation set of FLIM images. The output of this algorithm was a false-color image with each pixel color coded to represent the chemical composition of the sample. Surface areas occupied by elastin, collagen, and lipid components were then calculated and used to define the vulnerability of each imaged location. Four groups were defined: early lesion, stable, mildly vulnerable and extremely vulnerable. Each imaged location was categorized in one of the groups based on histopathology and classification results; sensitivities (SE) and specificities (SP) were calculated (SE %/SP %): early lesion: 95/96, stable: 71/97, mildly vulnerable: 75/94, and extremely vulnerable: 100/93. The capability of this algorithm to use FLIM images to quickly determine the chemical composition of atherosclerotic plaque, particularly related to vulnerability, further enhances the potential of this system for implementation as an intravascular diagnostic modality.

  17. A vascular biology network model focused on inflammatory processes to investigate atherogenesis and plaque instability

    PubMed Central

    2014-01-01

    Background Numerous inflammation-related pathways have been shown to play important roles in atherogenesis. Rapid and efficient