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1

Management of early postoperative coronary artery bypass graft failure  

PubMed Central

Perioperative graft failure following coronary artery bypass grafting (CABG) may result in acute myocardial ischaemia. Whether acute percutaneous coronary intervention, emergency reoperation or conservative intensive care treatment should be used is currently unknown. Between 2003 and 2009, 39 of the 5598 patients who underwent isolated CABG surgery underwent early postoperative coronary angiography for suspected myocardial ischaemia. Following angiography, two groups were identified: patients who underwent immediately reintervention (group 1); and those treated conservatively (group 2). Primary study endpoints were mortality and postoperative myocardial infarct size. Postoperative coronary angiography revealed early perioperative bypass graft failure in 32 of 39 patients. Acute percutaneous coronary intervention was performed in 15 patients, redo-CABG in 4 patients and conservative treatment in 13 patients. The number of failing bypass grafts were significantly higher in group 1 compared with group 2 (P = 0.0251). A trend toward lower post-procedural peak cardiac troponin T and creatinine phosphokinase serum levels in group 1 was observed (163.0 vs. 206.0 and 4.35 vs. 5.53, respectively) (P = 0.0662 and 0.1648). Early reintervention may limit the extent of myocardial cellular damage compared with conservative medical strategy in patients with myocardial ischaemia due to early graft failure. PMID:22223760

Laflamme, Maxime; DeMey, Nathalie; Bouchard, Denis; Carrier, Michel; Demers, Philippe; Pellerin, Michel; Couture, Pierre; Perrault, Louis P.

2012-01-01

2

Early Effects of Arterial Hemodynamic Conditions on Human Saphenous Veins Perfused Ex Vivo  

E-print Network

to promote vein graft remodeling are surgical preparation injury and exposure to the arterial hemodynamicEarly Effects of Arterial Hemodynamic Conditions on Human Saphenous Veins Perfused Ex Vivo Kreton--Exposure to the arterial hemodynamic environment is thought to be a potential trigger for the pathological remodeling

Chesler, Naomi C.

3

Liposomal nanoparticles encapsulating iloprost exhibit enhanced vasodilation in pulmonary arteries  

PubMed Central

Prostacyclin analogues are standard therapeutic options for vasoconstrictive diseases, including pulmonary hypertension and Raynaud’s phenomenon. Although effective, these treatment strategies are expensive and have several side effects. To improve drug efficiency, we tested liposomal nanoparticles as carrier systems. In this study, we synthesized liposomal nanoparticles tailored for the prostacyclin analogue iloprost and evaluated their pharmacologic efficacy on mouse intrapulmonary arteries, using a wire myograph. The use of cationic lipids, stearylamine, or 1,2-di-(9Z-octadecenoyl)-3-trimethylammonium-propane (DOTAP) in liposomes promoted iloprost encapsulation to at least 50%. The addition of cholesterol modestly reduced iloprost encapsulation. The liposomal nanoparticle formulations were tested for toxicity and pharmacologic efficacy in vivo and ex vivo, respectively. The liposomes did not affect the viability of human pulmonary artery smooth muscle cells. Compared with an equivalent concentration of free iloprost, four out of the six polymer-coated liposomal formulations exhibited significantly enhanced vasodilation of mouse pulmonary arteries. Iloprost that was encapsulated in liposomes containing the polymer polyethylene glycol exhibited concentration-dependent relaxation of arteries. Strikingly, half the concentration of iloprost in liposomes elicited similar pharmacologic efficacy as nonencapsulated iloprost. Cationic liposomes can encapsulate iloprost with high efficacy and can serve as potential iloprost carriers to improve its therapeutic efficacy. PMID:25045260

Jain, Pritesh P; Leber, Regina; Nagaraj, Chandran; Leitinger, Gerd; Lehofer, Bernhard; Olschewski, Horst; Olschewski, Andrea; Prassl, Ruth; Marsh, Leigh M

2014-01-01

4

Early neurological complications of coronary artery bypass surgery.  

PubMed Central

A prospective study of 312 patients undergoing elective coronary artery bypass surgery was undertaken to determine the incidence, severity, and functional impact of postoperative neurological complications. Detailed evaluation of the patients showed that neurological complications after surgery were common, occurring in 191 of the 312 patients (61%). Although such a high proportion of the total developed detectable changes, serious neurological morbidity was rare. Neurological disorders resulted in death in only one patient (0.3%) and severe disability in only four (1.3%). Forty eight patients were mildly disabled during the early postoperative period, and the remaining 138 with neurological signs had no serious functional disability. The postoperative neurological disorders detected included one death from cerebral hypoxic damage. Prolonged depression of conscious level was observed in 10 patients (3%) and definite stroke in 15 (5%); 78 (25%) developed ophthalmological abnormalities and 123 (39%) primitive reflexes; postoperative psychosis was observed in four (1%); and 37 (12%) developed disorders of the peripheral nervous system. The incidence of serious neurological problems such as fatal cerebral damage, stroke, and brachial plexopathy is in accordance with experience elsewhere. Lesser abnormalities, whose detection required detailed neurological examination, were much commoner than expected from previous reports. Images p1387-a PMID:2998539

Shaw, P J; Bates, D; Cartlidge, N E; Heaviside, D; Julian, D G; Shaw, D A

1985-01-01

5

Analysis of Turbulent flow in early stages of atherosclerosis of coronary artery  

NASA Astrophysics Data System (ADS)

During the early stages of atherosclerotic heart disease, fatty material accumulates in the coronary artery resulting in development of streaks of plaque and creating high levels of turbulence, and with significantly modified flow parameters. Diagnostic measures performed during this early stage may not show any evidence of coronary artery disease, because the lumen of the coronary artery has not decreased in caliber. These streaks do not obstruct the flow of blood but alter the flow characteristics, even at this preclinical stage. This talk presents the preliminary results for the analysis of turbulent flow characteristics for a range of atherosclerotic plaque configurations in the left main coronary artery. For this purpose a CAD/medical imaging based direct-simulation (DNS) tool has been developed. The Navier-stokes equations are solved in the vertical vorticity-velocity formulation. The plaque is introduced using immersed body technique. The geometric acquisition of the artery geometry and plaque morphology is obtained using CAD based commercial software.

Bhaganagar, Kiran

2005-11-01

6

URGENT REVASCULARIZATION OF LIVER ALLOGRAFTS AFTER EARLY HEPATIC ARTERY THROMBOSIS1  

PubMed Central

Between April 1993 and May 1995, 17 adult orthotopic liver transplant recipients were found to have early hepatic artery thrombosis (HAT) after a median of 7 postoperative days (mean, 11). The HAT was diagnosed in all cases by duplex ultrasound. Thrombectomy was performed with urgent revascularization (UR), using an interposition arterial graft procured from the cadaveric liver donor, and arterial patency was verified with intraoperative angiography. In seven cases, intra-arterial urokinase was administered after the thrombectomy. Fifteen (88%) of the livers remained arterialized throughout the follow-up period (median, 15 months); the remaining two patients developed recurrent HAT after 6 and 8 months. Although there was a high rate of subsequent complications, 11 (65%) of the patients are alive without retransplantation, with a mean follow-up of 17 months. Despite having a patent hepatic artery, the remaining six patients (35%) died from infectious complications that usually were present before the UR. Thus, UR effectively restored arterial inflow in 88% of the patients with early HAT. The ultimate outcome was determined mainly by the presence of intra-abdominal complications at the time of UR. In conclusion, UR, rather than retransplantation, should be considered the prime treatment option for patients who develop early posttransplant HAT. PMID:8970612

Pinna, Antonio D.; Smith, Craig V.; Furukawa, Hiro; Starzl, Thomas E.; Fung, John J.

2010-01-01

7

Predisease biological markers: early diagnosis and prevention of arterial hypertension  

Microsoft Academic Search

This review examines 2 potentially important morbid changes that may precede the onset of hypertension—capillary rarefaction (CR) and large artery rigidity (LAR). The mechanisms responsible for CR, currently measured in the skin microcirculation, as well those responsible for LAR, have yet to be fully delineated. Nor has the duration been determined of the latent period between the occurrence of these

Gérard E. Plante

2008-01-01

8

Signal and image processing for early detection of coronary artery diseases: A review  

NASA Astrophysics Data System (ADS)

Today biomedical signals and image based detection are a basic step to diagnose heart diseases, in particular, coronary artery diseases. The goal of this work is to provide non-invasive early detection of Coronary Artery Diseases relying on analyzing images and ECG signals as a combined approach to extract features, further classify and quantify the severity of DCAD by using B-splines method. In an aim of creating a prototype of screening biomedical imaging for coronary arteries to help cardiologists to decide the kind of treatment needed to reduce or control the risk of heart attack.

Mobssite, Youness; Samir, B. Belhaouari; Mohamad Hani, Ahmed Fadzil B.

2012-09-01

9

Busulphan-cyclophosphamide cause endothelial injury, remodeling of resistance arteries and enhanced expression of endothelial nitric oxide synthase.  

PubMed

Stem cell transplantation (SCT) is a curative treatment for malignant and non malignant diseases. However, transplantation-related complications including cardiovascular disease deteriorate the clinical outcome and quality of life. We have investigated the acute effects of conditioning regimen on the pharmacology, physiology and structure of large elastic arteries and small resistance-sized arteries in a SCT mouse model. Mesenteric resistance arteries and aorta were dissected from Balb/c mice conditioned with busulphan (Bu) and cyclophosphamide (Cy). In vitro isometric force development and pharmacology, in combination with RT-PCR, Western blotting and electron microscopy were used to study vascular properties. Compared with controls, mesenteric resistance arteries from the Bu-Cy group had larger internal circumference, showed enhanced endothelium mediated relaxation and increased expression of endothelial nitric oxide synthase (eNOS). Bu-Cy treated animals had lower mean blood pressure and signs of endothelial injury. Aortas of treated animals had a higher reactivity to noradrenaline. We conclude that short-term consequences of Bu-Cy treatment divergently affect large and small arteries of the cardiovascular system. The increased noradrenaline reactivity of large elastic arteries was not associated with increased blood pressure at rest. Instead, Bu-Cy treatment lowered blood pressure via augmented microvascular endothelial dependent relaxation, increased expression of vascular eNOS and remodeling toward a larger lumen. The changes in the properties of resistance arteries can be associated with direct effects of the compounds on vascular wall or possibly indirectly induced via altered translational activity associated with the reduced hematocrit and shear stress. This study contributes to understanding the mechanisms that underlie the early effects of conditioning regimen on resistance arteries and may help in designing further investigations to understand the late effects on vascular system. PMID:22303468

Al-Hashmi, Sulaiman; Boels, Piet J M; Zadjali, Fahad; Sadeghi, Behnam; Sällström, Johan; Hultenby, Kjell; Hassan, Zuzana; Arner, Anders; Hassan, Moustapha

2012-01-01

10

Early detection of pulmonary vascular disease in pulmonary arterial hypertension: time to move forward.  

PubMed

Pulmonary arterial hypertension (PAH) can be a rapidly progressive disorder and is associated with high rate of mortality, despite medical intervention. With the availability of effective therapy, early disease detection is an important strategic objective to improve treatment outcomes. Resting echocardiography is currently the recommended screening modality for high-risk population groups. However, it is clear that derangements in resting haemodynamics (and symptoms) are late sequelae of the pathobiological processes that begin in the distal pulmonary arteries. Exercise stress may unmask early pulmonary vascular dysfunction but the definition, clinical significance, and natural history of 'exercise PAH' remain undefined. We will review the currently available and potential future strategies aimed at early disease detection, and propose that ultimately the way forward is to detect disease at a stage prior to the rise in resting pulmonary artery pressure. PMID:21616950

Lau, Edmund M T; Manes, Alessandra; Celermajer, David S; Galiè, Nazzareno

2011-10-01

11

Intrathecal Morphine for Coronary Artery Bypass Grafting and Early Extubation  

Microsoft Academic Search

Aggressive control of pain during the immediate post- operative period after cardiac surgery with early tra- cheal extubation may decrease morbidity and mortal- ity. This prospective, randomized, double-blinded, placebo-controlled clinical study examined the use of intrathecal morphine in patients undergoing cardiac surgery and its influence on early tracheal extubation and postoperative analgesic requirements. Patients were randomized to receive either 10

Mark A. Chaney; Patricia A. Furry; Elaine M. Fluder; Stephen Slogoff

1997-01-01

12

Rupture of renal artery aneurysm during the early post-partum period.  

PubMed

Rupture of renal artery aneurysm associated with pregnancy is an uncommon condition. It is known that almost all previously reported cases have occurred during pregnancy. We experienced a case of rupture of renal artery aneurysm during the early post-partum period which was diagnosed by computed tomography and treated by angiographic embolization. To our knowledge, only two cases of rupture of renal artery aneurysm during the post-partum period have been reported in the English-language published work. An early diagnosis of rupture of renal artery aneurysm during the post-partum period is very challenging because the clinical symptoms of this condition are acute abdominal, flank or back pain, which are relatively common signs caused by more common post-partum complications. However, rupture of renal artery aneurysm is a life-threatening emergency condition requiring prompt diagnosis and treatment. The possibility of a rupture of renal artery aneurysm should be considered in any pregnant women with symptoms of an acute abdomen with hemorrhagic shock. PMID:23855369

Nakamura, Ryo; Koyama, Shinsuke; Maeda, Munehiro; Kobayashi, Masaki; Tanaka, Yusuke; Kubota, Satoshi; Isobe, Masanori; Shiki, Yasuhiko

2013-10-01

13

Surface Roughness Detection of Arteries via Texture Analysis of Ultrasound Images for Early Diagnosis of Atherosclerosis  

PubMed Central

There is a strong research interest in identifying the surface roughness of the carotid arterial inner wall via texture analysis for early diagnosis of atherosclerosis. The purpose of this study is to assess the efficacy of texture analysis methods for identifying arterial roughness in the early stage of atherosclerosis. Ultrasound images of common carotid arteries of 15 normal mice fed a normal diet and 28 apoE?/? mice fed a high-fat diet were recorded by a high-frequency ultrasound system (Vevo 2100, frequency: 40 MHz). Six different texture feature sets were extracted based on the following methods: first-order statistics, fractal dimension texture analysis, spatial gray level dependence matrix, gray level difference statistics, the neighborhood gray tone difference matrix, and the statistical feature matrix. Statistical analysis indicates that 11 of 19 texture features can be used to distinguish between normal and abnormal groups (p<0.05). When the 11 optimal features were used as inputs to a support vector machine classifier, we achieved over 89% accuracy, 87% sensitivity and 93% specificity. The accuracy, sensitivity and specificity for the k-nearest neighbor classifier were 73%, 75% and 70%, respectively. The results show that it is feasible to identify arterial surface roughness based on texture features extracted from ultrasound images of the carotid arterial wall. This method is shown to be useful for early detection and diagnosis of atherosclerosis. PMID:24146940

Niu, Lili; Qian, Ming; Yang, Wei; Meng, Long; Xiao, Yang; Wong, Kelvin K. L.; Abbott, Derek; Liu, Xin; Zheng, Hairong

2013-01-01

14

Mathematical Difficulty: Does Early Intervention Enhance Mathematical Performance?  

ERIC Educational Resources Information Center

The need to ask educators about their opinions on the subject to what extent early intervention methods enhance mathematical performance is long overdue. The purpose of this quantitative research is to examine the extent to which teachers agree that early intervention methods enhance the mathematical performance of students with mathematical…

Graham, Jennifer

2008-01-01

15

Attentional Enhancement via Selection and Pooling of Early Sensory Responses  

E-print Network

better by enhancing behavioral sensitivity and is associated with increased neural activity in earlyNeuron Article Attentional Enhancement via Selection and Pooling of Early Sensory ResponsesDepartment of Psychology and Center for Neural Science, New York University, New York, NY 10003, USA 3Mahoney

Carrasco, Marisa

16

Diagnostic value of contrast enhanced ultrasound for splenic artery complications following acute pancreatitis  

PubMed Central

AIM: To assess the value of contrast-enhanced ultrasound (CEUS) in diagnosing splenic artery complications (SACs) after acute pancreatitis (AP). METHODS: One hundred and eighteen patients with AP were enrolled in the study. All patients were examined by CEUS and contrast-enhanced computed tomography (CECT). CECT was accepted as a gold standard for the diagnosis of SACs in AP. The diagnostic accuracy of splenic CEUS and pancreatic CEUS was compared with that of CECT. Splenic infarction was the diagnostic criterion for splenic artery embolism and local dysperfusion of the splenic parenchyma was the diagnostic criterion for splenic arterial stenosis. The incidence of splenic sub-capsular hemorrhage, splenic artery aneurysms, and splenic rupture was all lower than that of SACs. RESULTS: Nine patients were diagnosed as having SACs after AP by CECT among the 118 patients. The patients with SACs were diagnosed with severe acute pancreatitis (SAP). Among them, 6 lesions were diagnosed as splenic artery embolism, 5 as splenic artery aneurysms, and 1 as splenic arterial stenosis. No lesion was diagnosed by pancreatic CEUS and 5 lesions were diagnosed by splenic CEUS. By splenic CEUS, 4 cases were diagnosed as splenic artery embolism and 1 as splenic arterial stenosis. The accuracy of splenic CEUS in diagnosis of SACs in SAP was 41.7% (5/12), which was higher than that of pancreatic CEUS (0%). CONCLUSION: Splenic CEUS is a supplementary method for pancreatic CEUS in AP patients, which can decrease missed diagnosis of SACs. PMID:24574783

Cai, Di-Ming; Parajuly, Shyam Sundar; Ling, Wen-Wu; Li, Yong-Zhong; Luo, Yan

2014-01-01

17

Uterine artery remodeling in pseudopregnancy is comparable to that in early pregnancy  

Microsoft Academic Search

During pregnancy, the lumenal diameter and wall mass of the uterine artery (UA) increase, most likely in response to the increased hemodynamic strain resulting from the chronically elevated uterine blood flow (UBF). In this remodeling process, the phenotype of vascular smooth-muscle cells (VSMC) is transiently altered to enable VSMC proliferation. These phenomena are already seen during early pregnancy, when the

O. W. H. van der Heijden; Y. P. Essers; M. E. A. Spaanderman; J. G. de Mey; G. van Eys; L. L. Peeters

2005-01-01

18

Morphological consequences of early reperfusion following thrombotic or mechanical occlusion of the rat middle cerebral artery  

Microsoft Academic Search

The early morphological consequences of recirculation following middle cerebral artery (MCA) occlusion were studied in two rat models. The proximal MCA was occluded for 1 h by either a surgical clip or platelet thrombus; subsequently, 1 h of recirculation was facilitated. Following clip occlusion and recirculation, mild astrocytic swelling, especially around blood vessels, was detected in reperfused cortical and striatal

W. D. Dietrich; H. Nakayama; B. D. Watson; H. Kanemitsu

1989-01-01

19

Cardiovascular magnetic resonance assessment of ventricular function and myocardial scarring before and early after repair of anomalous left coronary artery from the pulmonary artery  

PubMed Central

Background In patients with anomalous left coronary artery from the pulmonary artery (ALCAPA) left ventricular (LV) dilatation and dysfunction evolves due to diminished myocardial perfusion caused by coronary steal phenomenon. Using late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) imaging, myocardial scarring has been shown in ALCAPA patients late after repair, however the incidence of scarring before surgery and its impact on postoperative course after surgical repair remained unknown. Methods 8 ALCAPA-patients (mean age 10.0?±?5.8 months) underwent CMR before and early after (mean 4.9?±?2.5 months) coronary reimplantation procedures. CMR included functional analysis and LGE for detection of myocardial scars. Results LV dilatation (mean LVEDVI 171?±?94 ml/m2) and dysfunction (mean LV-EF 22?±?10 %) was present in all patients and improved significantly after surgery (mean LVEDV 68?±?42 ml/m2, p?=?0.02; mean LV-EF 58?±?19 %, p?artery and required resurgery. Conclusions Despite diminished myocardial perfusion and severely compromised LV function, myocardial scarring was preoperatively only infrequently present. Improvement of myocardial function was independent of new-onset scarring while the impact of preoperative scarring still needs to be defined. PMID:24387660

2014-01-01

20

Predisease biological markers: early diagnosis and prevention of arterial hypertension.  

PubMed

This review examines 2 potentially important morbid changes that may precede the onset of hypertension-capillary rarefaction (CR) and large artery rigidity (LAR). The mechanisms responsible for CR, currently measured in the skin microcirculation, as well those responsible for LAR, have yet to be fully delineated. Nor has the duration been determined of the latent period between the occurrence of these lesions and the onset of blood pressure elevation. It has been known for 2 decades that, because of the kidney's relatively rigid capsule, alterations in the abundant postglomerular microcirculation network (which can accommodate circa 80% of total renal blood flow) can lead to endothelial plasma leakage. Even a small amount of plasma leakage can increase interstitial pressure and lead to capillary collapse and CR. Simultaneously, or at a later time, these alterations could have an impact on the reflection wave profile in the thoracic aorta and, via abnormal endothelial proliferation and other vascular effects, give rise to LAR. Nonpharmacologic and/or pharmacologic interventions have been shown to exert positive effects on CR and/or LAR. Recent studies have demonstrated the beneficial actions of a bradykinin B2-receptor antagonist (HOE140) in the spontaneously hypertensive rat, the classic rat model for essential hypertension. The fact that CR and LAR both precede blood pressure elevation could serve as a basis for designing strategies to prevent hypertension from occurring. Because modern tools capable of measuring CR and LAR noninvasively have been developed, it should soon be feasible to identify these 2 prehypertension markers in individual patients. PMID:18803964

Plante, Gérard E

2008-10-01

21

Exercise training enhances multiple mechanisms of relaxation in coronary arteries from ischemic hearts.  

PubMed

Exercise training of coronary artery disease patients is of considerable interest, since it has been shown to improve vascular function and, thereby, enhance blood flow into compromised myocardial regions. However, the mechanisms underlying exercise-induced improvements in vascular function have not been fully elucidated. We tested the hypothesis that exercise training increases the contribution of multiple mediators to endothelium-dependent relaxation of coronary arteries in the underlying setting of chronic coronary artery occlusion. To induce gradual occlusion, an ameroid constrictor was placed around the proximal left circumflex coronary artery in Yucatan miniature swine. At 8 wk postoperatively, pigs were randomly assigned to sedentary or exercise (treadmill, 5 days/wk) regimens for 14 wk. Exercise training significantly enhanced the contribution of nitric oxide, prostanoids, and large-conductance Ca(2+)-dependent K(+) (BKCa) channels to endothelium-dependent, bradykinin-mediated relaxation in nonoccluded and collateral-dependent arteries. Combined nitric oxide synthase, prostanoid, and BKCa channel inhibition ablated the enhanced relaxation associated with exercise training. Exercise training significantly increased nitric oxide levels in response to bradykinin in endothelial cells isolated from nonoccluded and collateral-dependent arteries. Bradykinin treatment significantly increased PGI2 levels in all artery treatment groups and tended to be further enhanced after nitric oxide synthase inhibition in exercise-trained pigs. No differences were found in whole cell BKCa channel currents, BKCa channel protein levels, or arterial cyclic nucleotide levels. Although redundant, upregulation of parallel vasodilator pathways appears to contribute to enhanced endothelium-dependent relaxation, potentially providing a more refined control of blood flow after exercise training. PMID:23997097

Deer, Rachel R; Heaps, Cristine L

2013-11-01

22

Expression of Zinc Finger Immediate Early Genes in Rat Brain After Permanent Middle Cerebral Artery Occlusion  

Microsoft Academic Search

The prolonged expression of the leucine zipper fos\\/jun immediate early genes (IEG) has been correlated with neuronal death after cerebral ischemia. In this study, the expression of six zinc finger IEG was examined using in situ hybridization in adult rats after middle cerebral artery occlusion (MCAO) with the suture model. NGFI-A, NGFI-B, NGFI-C, egr-2, egr-3, and Nurr1 mRNA were all

Jari Honkaniemi; Bradley A. States; Philip R. Weinstein; Jose Espinoza; Frank R. Sharp

1997-01-01

23

Early detection of microstructural white matter changes associated with arterial pulsatility  

PubMed Central

Increased cerebral blood flow pulsatility is common in vascular dementia and is associated with macrostructural damage to cerebral white matter or leukoaraiosis (LA). In this study, we examine whether cerebral blood flow pulsatility is associated with macrostructural and microstructural changes in cerebral white matter in older adults with no or mild LA and no evidence of dementia. Diffusion Tensor Imaging was used to measure fractional anisotropy (FA), an index of the microstructural integrity of white matter, and radial diffusivity (RaD), a measure sensitive to the integrity of myelin. When controlling for age, increased arterial pulsation was associated with deterioration in both measures of white matter microstructure but not LA severity. A stepwise multiple linear regression model revealed that arterial pulsatility index was the strongest predictor of FA (R = 0.483, adjusted R2 = 0.220), followed by LA severity, but not age. These findings suggest that arterial pulsatility may provide insight into age-related reduction in white matter FA. Specifically, increased arterial pulsatility may increase perivascular shear stress and lead to accumulation of damage to perivascular oligodendrocytes, resulting in microstructural changes in white matter and contributing to proliferation of LA over time. Changes in cerebral blood flow pulsatility may therefore provide a sensitive index of white matter health that could facilitate the early detection of risk for perivascular white matter damage and the assessment of the effectiveness of preventative treatment targeted at reducing pulsatility. PMID:24302906

Jolly, Todd A. D.; Bateman, Grant A.; Levi, Christopher R.; Parsons, Mark W.; Michie, Patricia T.; Karayanidis, Frini

2013-01-01

24

Cerebrospinal Fluid from Patients with Subarachnoid Haemorrhage and Vasospasm Enhances Endothelin Contraction in Rat Cerebral Arteries  

PubMed Central

Introduction Previous studies have suggested that cerebrospinal fluid from patients with subarachnoid hemorrhage (SAH) leads to pronounced vasoconstriction in isolated arteries. We hypothesized that only cerebrospinal fluid from SAH patients with vasospasm would produce an enhanced contractile response to endothelin-1 in rat cerebral arteries, involving both endothelin ETA and ETB receptors. Methods Intact rat basilar arteries were incubated for 24 hours with cerebrospinal fluid from 1) SAH patients with vasospasm, 2) SAH patients without vasospasm, and 3) control patients. Arterial segments with and without endothelium were mounted in myographs and concentration-response curves for endothelin-1 were constructed in the absence and presence of selective and combined ETA and ETB receptor antagonists. Endothelin concentrations in culture medium and receptor expression were measured. Results Compared to the other groups, the following was observed in arteries exposed to cerebrospinal fluid from patients with vasospasm: 1) larger contractions at lower endothelin concentrations (p<0.05); 2) the increased endothelin contraction was absent in arteries without endothelium; 3) higher levels of endothelin secretion in the culture medium (p<0.05); 4) there was expression of ETA receptors and new expression of ETB receptors was apparent; 5) reduction in the enhanced response to endothelin after ETB blockade in the low range and after ETA blockade in the high range of endothelin concentrations; 6) after combined ETA and ETB blockade a complete inhibition of endothelin contraction was observed. Conclusions Our experimental findings showed that in intact rat basilar arteries exposed to cerebrospinal fluid from patients with vasospasm endothelin contraction was enhanced in an endothelium-dependent manner and was blocked by combined ETA and ETB receptor antagonism. Therefore we suggest that combined blockade of both receptors may play a role in counteracting vasospasm in patients with SAH. PMID:25629621

Assenzio, Barbara; Martin, Erica L.; Stankevicius, Edgaras; Civiletti, Federica; Fontanella, Marco; Boccaletti, Riccardo; Berardino, Maurizio; Mazzeo, AnnaTeresa; Ducati, Alessandro; Simonsen, Ulf; Mascia, Luciana

2015-01-01

25

Enhanced vasoconstrictor responses in renal and femoral arteries of the golden hamster during hibernation  

PubMed Central

The present study assessed local regulation of vascular tone of euthermic (control), cold control and hibernating golden hamsters. Sympathetic neurotransmission in the renal artery, the long term effects of hibernation on perivascular nerve activity, and the responsiveness of femoral artery to a number of neurotransmitters and hormones with both constrictor and dilator actions during hibernation are described.The contractile responses of the renal arterial rings to transmural nerve stimulation (80 V, 0.1 ms, 4–64 Hz, for 1 s) were negligible in controls, significantly increased at higher frequencies of stimulation in cold controls and markedly enhanced in the hibernating group at all frequencies tested. The contractile responses to exogenous noradrenaline (NA; 0.1–100 ?m) were significantly increased in the renal arteries of hibernating hamsters compared with controls, but not compared with cold controls. Responses to exogenous ATP (1–3000 ?m) and KCl (120 mm) were similar among all experimental groups.The maximal contractile responses of femoral arterial rings to the sympathetic co-transmitter ATP and 5-hydroxytryptamine were increased by approximately 124 % and 99 %, respectively, in hibernating compared with cold control preparations without a change in the concentration of agonist that produces half-maximal response. However, the responses to NA were not altered during hibernation.Vasoconstriction of femoral arterial rings in response to arginine vasopressin was significantly enhanced in both cold controls and hibernating groups, while vasoconstriction in response to endothelin-1 and KCl was unaltered.The dilator responses of femoral arterial rings to acetylcholine, sodium nitroprusside and adenosine were not different among the groups.It is suggested that the marked augmentation of sympathetic neurotransmission, selective supersensitivity of the vascular smooth muscle to sympathetic contractile agents and unaltered vasodilatory mechanisms may provide a means for maintenance of vascular tone and peripheral resistance during hibernation. PMID:9769433

Karoon, Parastoo; Knight, Gillian; Burnstock, Geoffrey

1998-01-01

26

Use of arterial to equilibrium enhancement washout to predict viability in liver cancers treated with transcatheter arterial chemoembolization  

NASA Astrophysics Data System (ADS)

Liver cancers are very common in Korea and Computed Tomography (CT) imaging is commonly used to diagnose them. This study improves the diagnosis of liver cancer by using a novel parametric image combining various phases of dynamic CT imaging. The objective of this study is to investigate the diagnostic value of arterial to equilibrium enhancement washout (AEEW) obtained by image registration and dynamic subtraction in predicting tumor viability in a hepatocellular carcinoma (HCC) treated with transcatheter arterial chemoembolization (TACE). Forty patients who had forty-seven iodized-oil defect areas (IODAs) in HCCs treated with TACE were included. These patients were divided into two groups, one group with viable tumors (n = 27) and the other group with non-viable tumors (n = 20) in the IODAs. All the patients underwent triple-phase CT before and after TACE. The attenuation differences of the IODAs between the arterial and the equilibrium phases were measured and compared between two groups. Quantitative AEEW color maps of the whole liver were created from the triple-phase CT image by using prototype research software. Two radiologists independently analyzed following two sets of image: one with standard tri-phase CT images and the other with tri-phase CT images and quantitative AEEW color map images. The diagnostic performances in terms of mean sensitivity, specificity, and accuracy for identifying viable or non-viable tumors by using quantitative AEEW color map images in addition to tri-phase CT was larger than the performance obtained using tri-phase CT only. In conclusion, quantitative AEEW color map images improve the diagnostic performances of multiphasic CT for determining the viability of the IODA in a HCC treated with TACE.

Choi, Seung Joon; Kim, Hyung Sik; Kim, Jeong Ho; Choi, Hye Young; Park, Hyunjin

2013-04-01

27

A Novel Vascular Homing Peptide Strategy to Selectively Enhance Pulmonary Drug Efficacy in Pulmonary Arterial Hypertension  

PubMed Central

A major limitation in the pharmacological treatment of pulmonary arterial hypertension (PAH) is the lack of pulmonary vascular selectivity. Recent studies have identified a tissue-penetrating homing peptide, CARSKNKDC (CAR), which specifically homes to hypertensive pulmonary arteries but not to normal pulmonary vessels or other tissues. Some tissue-penetrating vascular homing peptides have a unique ability to facilitate transport of co-administered drugs into the targeted cells/tissues without requiring physical conjugation of the drug to the peptide (bystander effect). We tested the hypothesis that co-administered CAR would selectively enhance the pulmonary vascular effects of i.v. vasodilators in Sugen5416/hypoxia/normoxia-exposed PAH rats. Systemically administered CAR was predominantly detected in cells of remodeled pulmonary arteries. Intravenously co-administered CAR enhanced pulmonary, but not systemic, effects of the vasodilators, fasudil and imatinib, in PAH rats. CAR increased lung tissue imatinib concentration in isolated PAH lungs without increasing pulmonary vascular permeability. Sublingual CAR was also effective in selectively enhancing the pulmonary vasodilation by imatinib and sildenafil. Our results suggest a new paradigm in the treatment of PAH, using an i.v./sublingual tissue-penetrating homing peptide to selectively augment pulmonary vascular effects of nonselective drugs without the potentially problematic conjugation process. CAR may be particularly useful as an add-on therapy to selectively enhance the pulmonary vascular efficacy of any ongoing drug treatment in patients with PAH. PMID:24401613

Toba, Michie; Alzoubi, Abdallah; O’Neill, Kealan; Abe, Kohtaro; Urakami, Takeo; Komatsu, Masanobu; Alvarez, Diego; Järvinen, Tero A.H.; Mann, David; Ruoslahti, Erkki; McMurtry, Ivan F.; Oka, Masahiko

2015-01-01

28

A novel vascular homing peptide strategy to selectively enhance pulmonary drug efficacy in pulmonary arterial hypertension.  

PubMed

A major limitation in the pharmacological treatment of pulmonary arterial hypertension (PAH) is the lack of pulmonary vascular selectivity. Recent studies have identified a tissue-penetrating homing peptide, CARSKNKDC (CAR), which specifically homes to hypertensive pulmonary arteries but not to normal pulmonary vessels or other tissues. Some tissue-penetrating vascular homing peptides have a unique ability to facilitate transport of co-administered drugs into the targeted cells/tissues without requiring physical conjugation of the drug to the peptide (bystander effect). We tested the hypothesis that co-administered CAR would selectively enhance the pulmonary vascular effects of i.v. vasodilators in Sugen5416/hypoxia/normoxia-exposed PAH rats. Systemically administered CAR was predominantly detected in cells of remodeled pulmonary arteries. Intravenously co-administered CAR enhanced pulmonary, but not systemic, effects of the vasodilators, fasudil and imatinib, in PAH rats. CAR increased lung tissue imatinib concentration in isolated PAH lungs without increasing pulmonary vascular permeability. Sublingual CAR was also effective in selectively enhancing the pulmonary vasodilation by imatinib and sildenafil. Our results suggest a new paradigm in the treatment of PAH, using an i.v./sublingual tissue-penetrating homing peptide to selectively augment pulmonary vascular effects of nonselective drugs without the potentially problematic conjugation process. CAR may be particularly useful as an add-on therapy to selectively enhance the pulmonary vascular efficacy of any ongoing drug treatment in patients with PAH. PMID:24401613

Toba, Michie; Alzoubi, Abdallah; O'Neill, Kealan; Abe, Kohtaro; Urakami, Takeo; Komatsu, Masanobu; Alvarez, Diego; Järvinen, Tero A H; Mann, David; Ruoslahti, Erkki; McMurtry, Ivan F; Oka, Masahiko

2014-02-01

29

Enhanced vasoconstriction to ?1-adrenoceptor stimulation during cooling in mouse cutaneous plantar arteries.  

PubMed

Cutaneous arteries are known to constrict in response to cooling via ?2C-adrenoceptors. The involvement of ?1-adrenoceptors in the cooling response has also recently been suggested by in vivo studies in mice. The present study was thus aimed to confirm it in the isolated mouse cutaneous plantar artery. Changes in vessel diameter were measured by pressurized arteriography. Myogenic constriction was induced depending on intraluminal pressure, and was nearly abolished by the Ca(2+) channel blocker nifedipine or by lowering bath temperature to 24°C. The ?1-adrenoceptor agonist phenylephrine produced two-phase constriction composed of phasic and tonic components, both of which were enhanced by the cooling to 24°C. Nifedipine partly inhibited the phenylephrine constriction at 37°C, and the nifedipine-resistant constriction was further inhibited by the inositol 1,4,5-trisphosphate (IP3) receptor inhibitor xestospongin C. Although the cooling to 24°C still enhanced the phenylephrine constriction in the presence of nifedipine, the enhancement was not observed in the presence of both nifedipine and xestospongin C. In Ca(2+)-free solution, phenylephrine produced two-phase constriction at 37°C, which was abolished by 30-min treatment with thapsigargin, an inhibitor of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA). In contrast, short-term treatment with thapsigargin for 3min rather enhanced the phenylephrine constriction in Ca(2+)-free solution at 37°C; however, the enhanced constriction by the cooling to 24°C was not further enhanced by the SERCA inhibitor. These results suggest that cooling inhibits Ca(2+) re-uptake by SERCA, thereby enhancing constriction induced by Ca(2+) released via IP3 receptors in the mouse plantar artery. PMID:25176180

Goto, Kazunori; Saito, Shin-Ya; Ishikawa, Tomohisa

2014-11-01

30

Risk factors and therapeutic results of early local recurrence after transcatheter arterial chemoembolization  

PubMed Central

AIM: To identify factors affecting early local recurrence after transcatheter arterial chemoembolization (TACE) and investigate treatments and outcomes for local recurrence. METHODS: Early local recurrence and no early local recurrence groups drawn from 134 patients who were initially diagnosed with hepatocellular carcinoma (HCC) and showed a complete response (CR) to TACE treatment between January 1, 2006, and January 31, 2012, were analyzed by univariate and multivariate analyses. Additionally, the subsequent treatment for patients with recurrence was analyzed, and in cases in which TACE had been performed, the cumulative recurrence rates were calculated using the Kaplan-Meier method and compared with those of the primary lesion. RESULTS: The 1-, 2-, and 3-year survival rates were 92.3%, 60.2%, and 39.8%, respectively, in the early local recurrence group, which were significantly lower than those in both the late local and no local recurrence groups (P < 0.001). On multivariate analyses, non-compact lipiodol uptake, large tumor size, and an alpha-fetoprotein > 20 ng/mL after achieving a CR were significant predictors. When TACE was performed for early and late locally recurrent lesions, a CR was observed in 15 patients (41.7%) and 11 patients (78.6%), and the cumulative recurrence rates at 6, 12, and 24 mo were 17.9%, 43.3%, and 71.2%, respectively, which did not differ significantly from those after the first CR of 20.5%, 44.0%, and 58.6%, respectively (P = 0.639). CONCLUSION: Closer monitoring and active treatments must be provided to patients with risk factors for early local recurrence of HCC. PMID:24944494

Rou, Woo Sun; Lee, Byung Seok; Moon, Hee Seok; Lee, Eaum Seok; Kim, Seok Hyun; Lee, Heon Young

2014-01-01

31

Role of Lipoxygenase Metabolites of Arachidonic Acid in Enhanced Pulmonary Artery Contractions of Female Rabbits  

PubMed Central

Pulmonary arterial hypertension is characterized by elevated pulmonary artery pressure and vascular resistance. In women the incidence is 4 fold greater than that in men. Studies suggest sustained vasoconstriction is a factor in increased vascular resistance. Possible vasoconstrictor mediators include arachidonic acid-derived lipoxygenase metabolites. Our studies in rabbits showed enhanced endothelium-dependent contractions to arachidonic acid in pulmonary arteries from females compared to males. Because treatment with a non-specific lipoxygenase inhibitor reduced contractions in females but not males, the present study identified which lipoxygenase isoform contributes to sex-specific pulmonary artery vasoconstriction. 15- and 5- but not 12-lipoxygenase protein expression was greater in females. Basal and A23187-stimulated release of 15-, 5- and 12-hydroxyeicosatetraenoic acid from females and males was measured by liquid chromatography/mass spectrometry. Only 15-hydroxyeicosatetraenoic acid synthesis was greater in females compared to males under both basal and stimulated conditions. Vascular contractions to 15-hydroxyeicosatetraenoic acid were enhanced in females compared to males (maximal contraction; 44 ± 6% vs 25 ± 3%). The specific 15-lipoxygenase inhibitor PD146176 (12 ?mol/L) decreased arachidonic acid-induced contractions in females (maximal contraction; 93 ± 4% vs 57 ± 10%). If male pulmonary arteries were incubated with estrogen (1 ?mol/L, 18 hrs), protein expression of 15-lipoxygenase, and 15-hydroxyeicosatetraenoic acid production increased. Mechanisms to explain the increased incidence of pulmonary hypertension in women are not known. Results suggest the 15-lipoxygenase pathway is different between females and males and is regulated by estrogen. Understanding this novel sex-specific mechanism may provide insight into the increased incidence of pulmonary hypertension in females. PMID:21300669

Pfister, Sandra L.

2011-01-01

32

Peripheral Artery Wall Imaging Using Contrast-Enhanced, Susceptibility Weighted Phase Imaging  

PubMed Central

Purpose To demonstrate improved delineation of peripheral artery wall in susceptibility weighted imaging (SWI) phase images by utilizing gadolinium contrast agent. Materials and methods Superficial femoral arteries were imaged using high resolution SWI in 11 healthy volunteers before, and after injection of gadopentetate dimeglumine. Two post-contrast scans started 1 min and 11 mins after injection respectively. Eight out of the 11 volunteers also underwent double-inversion-recovery (DIR) turbo-spin-echo (TSE) scans. The same resolution and matrix size were used between SWI and TSE studies, and TSE locations were matched to SWI images. Arterial lumen-wall phase difference and phase contrast-to-noise ratio (CNR) were measured and compared between pre- and post-contrast SWI measurements. The lumen and wall areas measured on both TSE and matching SWI images were respectively analyzed for agreement. Another 2 volunteers participated in a double-echo gradient-echo study. Results were compared to SWI. Results By injecting gadolinium contrast agent, phase difference changed by 54.5% and ?1.6%, and phase CNR changed by 85.7% and 27.0%, for the 1st and 2nd post-contrast scans respectively. Morphological measurements showed insignificant difference between TSE and SWIs based on paired t-tests; good agreements in Bland-Altman plots were achieved. The double-echo gradient-echo study had similar phase measurements as SWI. Conclusion Contrast-enhanced phase imaging improves artery wall delineation in SWI of peripheral artery wall. Contrast-enhanced SWI is a promising vessel wall imaging technique. PMID:22261774

Liu, Qi; Fan, Zhaoyang; Yang, Qi; Li, Debiao

2011-01-01

33

The Feasibility of Contrast-Enhanced Ultrasound During Uterine Artery Embolization: A Pilot Study  

SciTech Connect

Purpose. To evaluate the feasibility of using contrast-enhanced ultrasound (CEUS) during uterine artery embolization (UAE) in order to define the correct end-point of embolization with complete devascularization of all fibroids. Methods. In this prospective study of 10 consecutive women undergoing UAE, CEUS was performed in the angiographic suite during embolization. When the angiographic end-point, defined as the 'pruned-tree' appearance of the uterine arteries was reached, CEUS was performed while the angiographic catheters to both uterine arteries were kept in place. The decision whether or not to continue the embolization was based on the findings at CEUS. The results of CEUS were compared with those of contrast-enhanced magnetic resonance imaging (MRI) 1 day as well as 3 months following UAE. Results. CEUS was successfully performed in all women. In 4 cases injection of particles was continued based on the findings at CEUS despite angiographically complete embolization. CEUS imaging at completion of UAE correlated well with the findings at MRI. Conclusion. The use of CEUS during UAE is feasible and may increase the quality of UAE.

Dorenberg, Eric J., E-mail: eric.dorenberg@rikshospitalet.no; Jakobsen, Jarl A.; Brabrand, Knut; Hafsahl, Geir; Smith, Hans-Jorgen [Rikshospitalet-Radiumhospitalet Medical Center, Department of Radiology (Norway)

2007-09-15

34

Maturation enhances fluid shear-induced activation of eNOS in perfused ovine carotid arteries.  

PubMed

The present study tests the hypothesis that age-dependent increases in endothelial vasodilator capacity are due to maturational increases in endothelial nitric oxide (NO) synthesis and release. Intact 4-cm carotid artery segments taken from term fetal lambs and nonpregnant adult sheep were perfused by using a closed system that enabled independent control of flow and inflow pressure and facilitated complete recovery of all NO released. Fluid shear stress induced a graded release of NO (in nmol NO x min x cm(-2) of luminal surface area) that was significantly greater in adult (890 +/- 140) than in fetal (300 +/- 40) carotid arteries at corresponding values of shear stress (5.9 +/- 0.3 dyn/cm2) but was independent of inflow pressure in both age groups. These age-related differences in NO release were not attributable to corresponding differences in endothelial NO synthase (eNOS) abundance, as eNOS protein levels (in ng of eNOS/cm2 of luminal surface area) were similar in adult (14 +/- 2) and fetal (12 +/- 1) arteries. Adult (80 +/- 15) and fetal (89 +/- 32) levels of eNOS mRNA (in 10(6) copies/cm2 of luminal surface area) were also similar. However, when NO release was normalized relative to the associated mass of eNOS protein to estimate eNOS-specific activity in situ, this value (in nmol NO x microg of eNOS(-1) x min(-1)) was significantly greater in adult (177 +/- 44) than in fetal (97 +/- 36) arteries when the endothelium was maximally activated by A-23187. Similarly, the slope of the relation between fluid shear stress and estimated eNOS-specific activity (in nmol NO x microg of eNOS(-1) x min(-1) per dyn/cm2) was also significantly greater in adult (6.8 +/- 0.1) than in fetal (2.9 +/- 0.1) arteries, which suggests that eNOS may be more sensitive to or more efficiently coupled to activating stimuli in adult compared with fetal arteries. We conclude that maturational increases in endothelial vasodilator capacity are attributable to age-dependent increases in NO release secondary to elevated eNOS-specific activity and involve more efficient coupling between endothelial activation and enhancement of eNOS activity in adult compared with fetal arteries. PMID:15923310

White, Charles Ray; Hamade, Mohammad Wael; Siami, Koushan; Chang, Melody M; Mangalwadi, Anandit; Frangos, John A; Pearce, William J

2005-11-01

35

Early Development of Arterial Spin Labeling to Measure Regional Brain Blood Flow by MRI  

PubMed Central

Two major avenues of work converged in the late 1980’s and early 1990’s to give rise to brain perfusion MRI. The development of anatomical brain MRI quickly had as a major goal the generation of angiograms using tricks to label flowing blood in macroscopic vessels. These ideas were aimed at getting information about microcirculatory flow as well. Over the same time course the development of in vivo magnetic resonance spectroscopy had as its primary goal the assessment of tissue function and in particular, tissue energetics. For this the measurement of the delivery of water to tissue was critical for assessing tissue oxygenation and viability. The measurement of the washin/washout of “freely” diffusible tracers by spectroscopic based techniques pointed the way for quantitative approaches to measure regional blood flow by MRI. These two avenues came together in the development of arterial spin labeling (ASL) MRI techniques to measure regional cerebral blood flow. The early use of ASL to measure brain activation to help verify BOLD fMRI led to a rapid development of ASL based perfusion MRI. Today development and applications of regional brain blood flow measurements with ASL continues to be a major area of activity. PMID:22245338

Koretsky, Alan P.

2014-01-01

36

A nanostructured genosensor for the early diagnosis of systemic arterial hypertension.  

PubMed

The rapid progress of nanomedicine, especially in areas related to medical imaging and diagnostics, has motivated the development of new nanomaterials that can be combined with biological materials for specific medical applications. One such area of research involves the detection of specific DNA sequences for the early diagnosis of genetic diseases, using nanoparticles-containing genosensors. Typical genosensors devices are based on the use of sensing electrodes - biorecognition platforms - containing immobilized capture DNA probes capable of hybridizing with specific target DNA sequences. In this paper we show that upon an appropriate design of the biorecognition platform, efficient sandwich-type genosensors based upon DNA-AuNPs nanocomplexes can be efficiently applied to the detection of a Systemic Arterial Hypertension (SAH) polymorphism located in intron 16 of the Angiotensin-converter enzyme (ACE) gene. Since SAH is intimately related to heart diseases, especially blood hypertension, its early detection is of great biomedical interest. The biorecognition platforms were assembled using mixed self-assembled monolayers (SAMmix), which provided the immobilization of organized architectures with molecular control. Detection of the DNA target sequence at concentrations down to 1 nM was carried out using electrochemical impedance spectroscopy (EIS). We show that the use of EIS combined with specific nanobiocomplexes represents an efficient method for the unambiguous detection of complementary DNA hybridization for preventative nanomedicine applications. PMID:25653060

Rolim, Thalita; Cancino, Juliana; Zucolotto, Valtencir

2015-02-01

37

Nogo-B expression, in arterial intima, is impeded in the early stages of atherosclerosis in humans.  

PubMed

Nogo-B (Reticulon 4B) is considered to be a novel vascular marker, which may have a protective role in injury-induced neointima formation and atherosclerosis. Nogo A/B is found to be crucial for monocyte/macrophage recruitment in acute inflammation and it is expressed in CD68 + macrophages. We hypothesize that macrophage infiltration in atherosclerosis is not dependent on Nogo-B expression in arterial wall. We have assessed Nogo-B expression and macrophage accumulation in the iliac arteries of healthy organ donors and organ donors with cardiovascular risk factors. Paraffin sections of 66 iliac arteries, from 44 deceased organ donors (17 women and 27 men), were studied. The healthy and cardiovascular risk (CVR) subgroups were created. With regard to staging of the atherosclerotic process, the thickness of arterial intima was measured in digitalized images of H+E stained tissue sections. Immunohistochemical reactions (Nogo-B and CD68) were carried out in all arteries (66 samples). Western blotting (WB-19 samples) and real-time PCR (27 samples) were performed on selected arteries. Significantly higher Nogo-B expression was demonstrated in the intima of the healthy subjects' subgroup, using immunohistochemistry. WB and real-time PCR revealed a trend toward lower Nogo-B expression in the adventitia of the CVR subgroup. Furthermore, the thickness of the intima was found to negatively correlate with the expression of Nogo-B in the intima and media (r = -0.32; p < 0.05; r = -0.32; p < 0.05). Macrophage infiltrates were more prominent in intima of CVR subjects (0.65 vs 3.52 a.u.; p < 0.01). Macrophage density in intima increased with atherosclerosis progression (r = 0.37; p < 0.01). CD68 macrophages density in adventitia was lower in CVR arteries than in healthy arteries. The expression of Nogo-B, in arterial intima, is impeded in the early stages of atherosclerosis. Accumulation of arterial intimal CD68 macrophages has been shown to progress; however, the overall macrophage density in the adventitia is reduced in arteries shown to have intimal thickening. Macrophage infiltration is not accompanied by Nogo-B expression in atherosclerotic arteries. PMID:24372562

Dro?d?, Katarzyna; Grzegorek, Irmina; Chmielewska, Magdalena; Gomu?kiewicz, Agnieszka; Jab?o?ska, Karolina; Piotrowska, Aleksandra; Karczewski, Maciej; Janczak, Dariusz; Patrza?ek, Dariusz; Dzi?giel, Piotr; Szuba, Andrzej

2014-09-01

38

A Multicenter, Prospective Study to Evaluate the Use of Contrast Stress Echocardiography in Early Menopausal Women at Risk for Coronary Artery Disease: Trial Design and Baseline Findings  

PubMed Central

Abstract Aims This multisite prospective trial, Stress Echocardiography in Menopausal Women At Risk for Coronary Artery Disease (SMART), aimed to evaluate the prognostic value of contrast stress echocardiography (CSE), coronary artery calcification (CAC), and cardiac biomarkers for prediction of cardiovascular events after 2 and 5 years in early menopausal women experiencing chest pain symptoms or risk factors. This report describes the study design, population, and initial test results at study entry. Methods From January 2004 through September 2007, 366 early menopausal women (age 54±5 years, Framingham risk score 6.51%±4.4 %, range 1%–27%) referred for stress echocardiography were prospectively enrolled. Image quality was enhanced with an ultrasound contrast agent. Tests for cardiac biomarkers [high-sensitivity C-reactive protein (hsCRP), atrial natriuretic protein (ANP), brain natriuretic protein (BNP), endothelin (ET-1)] and cardiac computed tomography (CT) for CAC were performed. Results CSE (76% exercise, 24% dobutamine) was abnormal in 42 women (11.5%), and stress electrocardiogram (ECG) was positive in 22 women (6%). Rest BNP correlated weakly with stress wall motion score index (WMSI) (r=0.189, p<0.001). Neither hsCRP, ANP, endothelin, nor CAC correlated with stress WMSI. Predictors of abnormal CSE were body mass index (BMI), diabetes mellitus, family history of premature coronary artery disease (CAD), and positive stress ECG. Twenty-four women underwent clinically indicated coronary angiography (CA); 5 had obstructive (?50%), 15 had nonobstructive (10%–49%), and 4 had no epicardial CAD. Conclusions The SMART trial is designed to assess the prognostic value of CSE in early menopausal women. Independent predictors of positive CSE were BMI, diabetes mellitus, family history of premature CAD, and positive stress ECG. CAC scores and biomarkers (with the exception of rest BNP) were not correlated with CSE results. We await the follow-up data. PMID:23398128

Abdelmoneim, Sahar S.; Bernier, Mathieu; Hagen, Mary E.; Eifert-Rain, Susan; Bott-Kitslaar, Dalene; Wilansky, Susan; Castello, Ramon; Bhat, Gajanan; Pellikka, Patricia A.; Best, Patricia J. M.; Hayes, Sharonne N.

2013-01-01

39

Comparison of intraoperative transit-time flow measurement with early postoperative magnetic resonance flow mapping in off-pump coronary artery surgery.  

PubMed

The purpose of this prospective study was to evaluate graft patency of off-pump coronary artery surgery intraoperatively by transit-time flow measurement and to compare this technique with postoperative magnetic resonance flow mapping. Twenty patients (13 men and 7 women; mean age, 679 +/- 76 yr) underwent off-pump coronary artery surgery. Intraoperative transit-time flow measurement of grafts was performed measuring maximum, minimum, and mean flows. For each graft, the pulsatile index was calculated by dividing the difference between the maximum and the minimum flow by the mean flow In the early postoperative period (1st week), magnetic resonance flow mapping was performed using phase contrast flow quantification. Mean intraoperative flow values and mean magnetic resonance flow mapping values were compared. At the same postoperative session, contrast-enhanced magnetic resonance angiography was performed to evaluate graft patency. In 20 patients, a total of 49 coronary graft flows were assessed with intraoperative transit-time flow measurement and postoperative magnetic resonance flow mapping. Upon comparison, there was a strong correlation between techniques, with stable and statistically significant differences between the intraoperative and postoperative flow mapping values. One saphenous vein graft was revised intraoperatively, due to graft failure. Our data suggest that the combined use of intraoperative transit-time flow measurement and postoperative magnetic resonance flow analysis has a potential role in the assessment of graft patency in off-pump coronary artery surgery although more study is required. PMID:12638668

Sanisoglu, Ilhan; Guden, Mustafa; Balci, Cem; Sagbas, Ertan; Duran, Cihan; Akpinar, Belhhan

2003-01-01

40

STIM2 contributes to enhanced store-operated Ca2+ entry in pulmonary artery smooth muscle cells from patients with idiopathic pulmonary arterial hypertension  

PubMed Central

Pulmonary vasoconstriction and vascular remodeling are two major causes for elevated pulmonary vascular resistance and pulmonary arterial pressure in patients with idiopathic pulmonary arterial hypertension (IPAH). An increase in cytosolic free Ca2+concentration ([Ca2+]cyt) in pulmonary artery smooth muscle cells (PASMC) is a major trigger for pulmonary vasoconstriction and an important stimulus for PASMC proliferation, which causes pulmonary vascular remodeling. Store-operated Ca2+ entry (SOCE), induced by depletion of stored Ca2+ in the sarcoplasmic reticulum (SR), can increase [Ca2+]cyt in PASMC, independent of other means of Ca2+ entry. Stromal interaction molecule (STIM) proteins, STIM1 and STIM2, were both recently identified as sensors for store depletion and also signaling molecules to open store-operated Ca2+ channels. We previously reported that SOCE was significantly enhanced in PASMC from IPAH patients compared to PASMC from normotensive control subjects. Enhanced SOCE plays an important role in the pathophysiological changes in PASMC associated with pulmonary arterial hypertension. In this study, we examine whether the expression levels of STIM1 and STIM2 are altered in IPAH-PASMC compared to control PASMC, and whether these putative changes in the STIM1 and STIM2 expression levels are responsible for enhanced SOCE and proliferation in IPAH-PASMC. Compared to control PASMC, the protein expression level of STIM2 was significantly increased in IPAH-PASMC, whereas STIM1 protein expression was not significantly changed. In IPAH-PASMC, the small interfering RNA (siRNA)-mediated knockdown of STIM2 decreased SOCE and proliferation, while knockdown of STIM2 in control PASMC had no effect on either SOCE or proliferation. Overexpression of STIM2 in the control PASMC failed to enhance SOCE or proliferation. These data indicate that enhanced protein expression of STIM2 is necessary, but not sufficient, for enhanced SOCE and proliferation of IPAH-PASMC. PMID:21709766

Song, Michael Y.; Makino, Ayako; Yuan, Jason X.-J.

2011-01-01

41

New phenotypic aspects of the decidual spiral artery wall during early post-implantation mouse pregnancy  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Spiral artery (SA) wall remodeling (SAR) is ill-defined and clinically important. Black-Right-Pointing-Pointer SA muscular phenotype prior to and during SAR in mice is underexplored. Black-Right-Pointing-Pointer SA muscular wall consists of contractile and non-contractile components. Black-Right-Pointing-Pointer SA wall non-contractile component may be synthetic smooth muscle. Black-Right-Pointing-Pointer Timing and extent of SA wall contractile component loss is revealed. -- Abstract: During pregnancy the walls of decidual spiral arteries (SAs) undergo clinically important structural modifications crucial for embryo survival/growth and maternal health. However, the mechanisms of SA remodeling (SAR) are poorly understood. Although an important prerequisite to this understanding is knowledge about the phenotype of SA muscular wall prior to and during the beginning of mouse SAR, this remains largely unexplored and was the main aim of this work. Using histological and immunohistochemical techniques, this study shows for the first time that during early mouse gestation, from embryonic day 7.5 (E7.5) to E10.5, the decidual SA muscular coat is not a homogeneous structure, but consists of two concentric layers. The first is a largely one cell-thick sub-endothelial layer of contractile mural cells (positive for {alpha}-smooth muscle actin, calponin and SM22{alpha}) with pericyte characteristics (NG2 positive). The second layer is thicker, and evidence is presented that it may be of the synthetic/proliferative smooth muscle phenotype, based on absence ({alpha}-smooth muscle actin and calponin) or weak (SM22{alpha}) expression of contractile mural cell markers, and presence of synthetic smooth muscle characteristics (expression of non-muscle Myosin heavy chain-IIA and of the cell proliferation marker PCNA). Importantly, immunohistochemistry and morphometrics showed that the contractile mural cell layer although prominent at E7.5-E8.5, becomes drastically reduced by E10.5 and is undetectable by E12.5. In conclusion, this study reveals novel aspects of the decidual SA muscular coat phenotype prior to and during early SAR that may have important implications for understanding the mechanisms of SAR.

Elia, Artemis; Charalambous, Fotini [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)] [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus); Georgiades, Pantelis, E-mail: pgeor@ucy.ac.cy [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)] [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)

2011-12-09

42

Enhancing the pulse contour analysis-based arterial stiffness estimation using a novel photoplethysmographic parameter.  

PubMed

In this paper, we propose a novel method for enhancing pulse contour analysis-based arterial stiffness estimation using a simple and low-complexity photoplethysmographic parameter (P2Ocd). The method first eliminates baseline wanders in the digital volume pulse (DVP) by applying a simple morphological filter. The filtered DVP signal is then transformed into a slope sum function signal to simplify the pulse peak detection process by enhancing the upslope of the DVP signal while suppressing its downslope. An adaptive thresholding scheme is applied to detect pulse peaks from the transformed signal. Pulse onsets are then identified as the minimum values between consecutive pulse peaks. The P2Ocd is finally calculated by dividing the time interval between the pulse peak and the pulse onset by the pulse length. In order to assess the agreement of the P2Ocd with an established technique, brachial-ankle pulse wave velocity, we performed Bland-Altman and correlation analyses. Furthermore, we evaluated the P2Ocd-based arterial stiffness estimation in terms of prediction accuracy (% error rate) and repeatability (coefficient of variation). The results show that the proposed measurement agrees well with the established technique and shows a high repeatability; it also has a better predictive accuracy than that of conventional methods. In addition, we show that the proposed parameter further improves the predictive accuracy by combining it with age. The proposed method is therefore highly applicable to small ubiquitous healthcare applications. PMID:25561448

Jang, Dae-Geun; Park, Seung-Hun; Hahn, Minsoo

2015-01-01

43

Sequence Comparison for Non-Enhanced MRA of the Lower Extremity Arteries at 7 Tesla  

PubMed Central

In this study three sequences for non-contrast-enhanced MRA of the lower extremity arteries at 7T were compared. Cardiac triggering was used with the aim to reduce signal variations in the arteries. Two fast single-shot 2D sequences, a modified Ultrafast Spoiled Gradient Echo (UGRE) sequence and a variant of the Quiescent-Interval Single-Shot (QISS) sequence were triggered via phonocardiogram and compared in volunteer examinations to a non-triggered 2D gradient echo (GRE) sequence. For image acquisition, a 16-channel transmit/receive coil and a manually positionable AngioSURF table were used. To tackle B1 inhomogeneities at 7T, Time-Interleaved Acquisition of Modes (TIAMO) was integrated in GRE and UGRE. To compare the three sequences quantitatively, a vessel-to-background ratio (VBR) was measured in all volunteers and stations. In conclusion, cardiac triggering was able to suppress flow artifacts satisfactorily. The modified UGRE showed only moderate image artifacts. Averaged over all volunteers and stations, GRE reached a VBR of 4.18±0.05, UGRE 5.20±0.06, and QISS 2.72±0.03. Using cardiac triggering and TIAMO imaging technique was essential to perform non-enhanced MRA of the lower extremities vessels at 7T. The modified UGRE performed best, as observed artifacts were only moderate and the highest average VBR was reached. PMID:24454963

Johst, Sören; Orzada, Stephan; Fischer, Anja; Schäfer, Lena C.; Nassenstein, Kai; Umutlu, Lale; Lauenstein, Thomas C.; Ladd, Mark E.; Maderwald, Stefan

2014-01-01

44

Dealing with Coronary Artery Disease in Early Encountering: A Qualitative Study  

PubMed Central

Background: The prevalence of cardiovascular diseases is rising in industrial and developing countries. Coronary Artery Disease (CAD) is the most common cardiovascular disease. Thus, understanding the signs and risk factors of CAD from the patients’ perspective and their ways of dealing with this disease is of vital importance. Objectives: This qualitative study aimed to explore the Iranian patients’ viewpoints about CAD and how they dealt with it in their first encounter. Patients and Methods: This study was a qualitative content analysis conducted on 18 patients with CAD. The data were collected through semi-structured interviews. Initially, purposeful sampling was performed followed by maximum variety. Sampling continued until data saturation. Then, all the interviews were recorded and transcribed verbatim. After all, the data were analyzed by constant comparative analysis using MAXQUDA2010 software. Results: The themes manifested in this study included “invasion of disease” with subthemes of “warning signs” and “risk factors” and “confrontation strategies” with subthemes of “seeking for information”, “follow-up”, and “control measures”. Conclusions: The results of this study described the patients’ perceptions of CAD and how they dealt with this disorder in early encountering. Based on the results, physicians and nurses should focus on empowerment of patients by facilitating this process as well as by educating them with regards to dealing with CAD.

Mojalli, Mohammad; Karimi Moonaghi, Hossein; Khosravan, Shahla; Mohammadpure, Ali

2014-01-01

45

Use of Intra-Arterial Carbon-Dioxide-Enhanced Ultrasonography for Guidance of Radiofrequency Ablation and Transcatheter Arterial Chemoembolization in Hepatocellular Carcinoma  

SciTech Connect

A 73-year-old man with hepatitis-C-related cirrhosis and an elevated alpha-fetoprotein level and tumor in segment 3 of his liver was referred for interventional radiologic treatment. He was not a candidate for surgical resection due to impaired liver function and his personal preferences. On conventional ultrasonography no lesion could be detected, but the tumor was clearly depicted by intra-arterial carbon-dioxide-enhanced ultrasonography. Radiofrequency ablation was performed safely and accurately under the guidance of carbon-dioxide-enhanced ultrasonography. By concomitant performance of transcatheter arterial chemoembolization with radiofrequency ablation, extensive necrosis was obtained and adequate tumor volume reduction achieved with only one treatment session.

Ohmoto, Kenji, E-mail: ohmotok@med.kawasaki-m.ac.jp; Yoshioka, Naoko; Tomiyama, Yasuyuki; Shibata, Norikuni; Kawase, Tomoya; Yoshida, Koji; Kuboki, Makoto; Yamamoto, Shinichiro [Kawasaki Medical School, Division of Hepatology, Department of Medicine (Japan)

2006-12-15

46

Impact of perioperative myocardial injury on early and long-term outcome after coronary artery bypass grafting  

Microsoft Academic Search

Aims To establish the influence of perioperative myocar- dial injury on short- and long-term survival after coronary artery bypass grafting (CABG). Methods and Results The correlation of postoperative serum aspartate aminotransferase and creatine kinase MB to early cardiac-related death and to late survival was evaluated in 4911 patients who underwent CABG consecu- tively during a 6-year period. There were 93

J. Steuer; L.-G. Horte; B. Lindahl; E. Sta

47

Maternal Characteristics, Mean Arterial Pressure and Serum Markers in Early Prediction of Preeclampsia  

PubMed Central

Objectives In a previous study, we have described the predictive value of first-trimester Pregnancy-Associated Plasma Protein-A (PAPP-A), free ?-subunit of human Chorionic Gonadotropin (f?-hCG), Placental Growth Factor (PlGF) and A Disintegrin And Metalloprotease 12 (ADAM12) for early onset preeclampsia (EO-PE; delivery <34 weeks). The objective of the current study was to obtain the predictive value of these serum makers combined with maternal characteristics and first-trimester maternal mean arterial blood pressure (MAP) in a large series of patients, for both EO-PE and late onset PE (LO-PE; delivery ? 34 weeks). Methods This was a nested case-control study, using stored first-trimester maternal serum from women who developed EO-PE (n?=?68) or LO-PE (n?=?99), and 500 uncomplicated singleton pregnancies. Maternal characteristics, MAP, and pregnancy outcome were collected for each individual woman and used to calculate prior risks for PE in a multiple logistic regression model. Models containing prior PE risks, serum markers, and MAP were developed for the prediction of EO-PE and LO-PE. The model-predicted detection rates (DR) for fixed 10% false-positive rates were calculated for EO-PE and LO-PE with or without the presence of a small-for-gestational age infant (SGA, birth weight <10th centile). Results The best prediction model included maternal characteristics, MAP, PAPP-A, ADAM12, and PlGF, with DR of 72% for EO-PE and 49% for LO-PE. Prediction for PE with concomitant SGA was better than for PE alone (92% for EO-PE and 57% for LO-PE). Conclusion First-trimester MAP, PAPP-A, ADAM12, and PlGF combined with maternal characteristics and MAP are promising markers in the risk assessment of PE, especially for EO-PE complicated by SGA. PMID:23717445

Kuc, Sylwia; Koster, Maria P. H.; Franx, Arie; Schielen, Peter C. J. I.; Visser, Gerard H. A.

2013-01-01

48

Early Repolarization and Myocardial Scar Predict Poorest Prognosis in Patients with Coronary Artery Disease  

PubMed Central

Purpose Recent studies show positive association of early repolarization (ER) with the risk of life-threatening arrhythmias in patients with coronary artery disease (CAD). This study was to investigate the relationships of ER with myocardial scarring and prognosis in patients with CAD. Materials and Methods Of 570 consecutive CAD patients, patients with and without ER were assigned to ER group (n=139) and no ER group (n=431), respectively. Myocardial scar was evaluated using cardiac single-photon emission computed tomography. Results ER group had previous history of myocardial infarction (33% vs. 15%, p<0.001) and lower left ventricular ejection fraction (57±13% vs. 62±13%, p<0.001) more frequently than no-ER group. While 74 (53%) patients in ER group had myocardial scar, only 121 (28%) patients had in no-ER group (p<0.001). During follow up, 9 (7%) and 4 (0.9%) patients had cardiac events in ER and no-ER group, respectively (p=0.001). All patients with cardiac events had ER in inferior leads and horizontal/descending ST-segment. Patients with both ER in inferior leads and horizontal/descending ST variant and scar had an increased adjusted hazard ratio of cardiac events (hazard ratio 16.0; 95% confidence interval: 4.1 to 55.8; p<0.001). Conclusion ER in inferior leads with a horizontal/descending ST variant was associated with increased risk of cardiac events. These findings suggest that ER in patients with CAD may be related to myocardial scar rather than pure ion channel problem. PMID:24954320

Lee, Hye-Young; Mun, Hee-Sun; Wi, Jin; Uhm, Jae-Sun; Shim, Jaemin; Kim, Jong-Youn; Pak, Hui-Nam; Lee, Moon-Hyoung

2014-01-01

49

[Hemodynamic features assessment in submental and facial arteries in patients with early atherosclerotic disease of brachycephalic arteries].  

PubMed

By ultrasonicduplex scanning nature estimated haemodynamics in the arteriessubmentalis and facial of patients with early signs of atherosclerotic changes in the brakhiotsefalarteries and periodontal pathology of different stages - for perfection of prophylaxis of periodontal diseases by the means of investigation of prophylaxis vascular diseases. It was established, that influence of risk factors is more important than the age of patients. PMID:25588335

Nadtochi?, A G; Grudianov, A I; Avraamova, T V

2014-01-01

50

Musicians' Enhanced Neural Differentiation of Speech Sounds Arises Early in Life: Developmental Evidence from Ages 3 to 30  

E-print Network

Musicians' Enhanced Neural Differentiation of Speech Sounds Arises Early in Life: Developmental; this training may generalize to speech processing given that adult musicians have enhanced neural. Results reveal that musicians exhibit enhanced neural differentiation of stop consonants early in life

Kraus, Nina

51

Relation of Subclinical Coronary Artery Atherosclerosis to Cerebral White Matter Disease in Healthy Individuals from Families with Early-Onset Coronary Artery Disease  

PubMed Central

White matter disease (WMD) of the brain is associated with incident stroke. Similarly subclinical calcified coronary artery plaque has been associated with incident coronary artery disease (CAD) events. Although atherogenesis in both vascular beds may share some common mechanisms, the extent to which subclinical CAD is associated with WMD across age ranges in individuals with a family history of early onset CAD remains unknown. We screened 405 apparently healthy participants in the Genetic Study of Atherosclerotic Risk (GeneSTAR) for CAD risk factors, and for the presence of noncalcified and calcified coronary plaque using dual-source multi-detector cardiac CT angiography. The presence and volumes of WMD were assessed by 3 Tesla brain MRI. Participants were 60% female, 36% African American; mean age 51.6 ± 10.6 years. The prevalence of coronary plaque overall was 43.0%. Individuals with coronary plaque had significantly higher WMD volumes (median 1222 mm3, IQR [448 to 3871]) compared to those without coronary plaque (median 551 mm3, IQR [105 to 1523], p<0.001). In multivariable regression analysis, adjusting for age, sex, race, traditional risk factors, total brain volume, and intrafamilial correlations, the presence of coronary plaque was independently associated with WMD volume (p=0.05). This study shows a significant association between WMD and noncalcified and calcified coronary plaque in healthy individuals, independent of age and risk factors. In conclusion, these findings support the premise of possible shared causal pathways in two vascular beds in families at increased risk for early-onset vascular disease. PMID:23742943

Kral, Brian G.; Nyquist, Paul; Vaidya, Dhananjay; Yousem, David; Yanek, Lisa R.; Fishman, Elliot K.; Becker, Lewis C.; Diane M., Becker

2013-01-01

52

Cutting-Balloon Angioplasty in Transplant Renal Artery Stenosis as First-Line Treatment in the Early Postoperative Period  

SciTech Connect

Percutaneous transluminal angioplasty has been successfully used for the treatment of transplant renal artery stenosis (RAS). Cutting-balloon angioplasty (CBA) is being used as a second option in pressure-resistant stenosis. It is thought that CBA is less traumatic and therefore restenosis occurs less frequently than in conventional angioplasty. This case report describes the unusual use of a cutting balloon in transplant RAS as a first option in the early postoperative period. Long-term follow-up data are also presented.

Ucar, Adem, E-mail: ucaradem@yahoo.com [Istanbul University, Interventional Radiology Department, Istanbul Faculty of Medicine (Turkey); Yahyayev, Aghakishi, E-mail: aghakishi@yahoo.com [Istanbul University, Radiology Department, Istanbul Faculty of Medicine (Turkey); Bakkaloglu, Huseyin, E-mail: drhuseyin@yahoo.com [Istanbul University, Transplantlogy Department, General Surgery, Istanbul Faculty of Medicine (Turkey); Agayev, Ayaz, E-mail: ayazagayev@gmail.com [Istanbul University, Radiology Department, Istanbul Faculty of Medicine (Turkey); Aydin, Ali Emin, E-mail: alieminaydin@hotmail.com [Istanbul University, Transplantlogy Department, General Surgery, Istanbul Faculty of Medicine (Turkey); Rozanes, Izzet, E-mail: rozanes@superonline.com [Istanbul University, Interventional Radiology Department, Istanbul Faculty of Medicine (Turkey)

2011-02-15

53

Operational real-time GPS-enhanced earthquake early warning  

NASA Astrophysics Data System (ADS)

Moment magnitudes for large earthquakes (Mw?7.0) derived in real time from near-field seismic data can be underestimated due to instrument limitations, ground tilting, and saturation of frequency/amplitude-magnitude relationships. Real-time high-rate GPS resolves the buildup of static surface displacements with the S wave arrival (assuming nonsupershear rupture), thus enabling the estimation of slip on a finite fault and the event's geodetic moment. Recently, a range of high-rate GPS strategies have been demonstrated on off-line data. Here we present the first operational system for real-time GPS-enhanced earthquake early warning as implemented at the Berkeley Seismological Laboratory (BSL) and currently analyzing real-time data for Northern California. The BSL generates real-time position estimates operationally using data from 62 GPS stations in Northern California. A fully triangulated network defines 170+ station pairs processed with the software trackRT. The BSL uses G-larmS, the Geodetic Alarm System, to analyze these positioning time series and determine static offsets and preevent quality parameters. G-larmS derives and broadcasts finite fault and magnitude information through least-squares inversion of the static offsets for slip based on a priori fault orientation and location information. This system tightly integrates seismic alarm systems (CISN-ShakeAlert, ElarmS-2) as it uses their P wave detections to trigger its processing; quality control runs continuously. We use a synthetic Hayward Fault earthquake scenario on real-time streams to demonstrate recovery of slip and magnitude. Reanalysis of the Mw7.2 El Mayor-Cucapah earthquake tests the impact of dynamic motions on offset estimation. Using these test cases, we explore sensitivities to disturbances of a priori constraints (origin time, location, and fault strike/dip).

Grapenthin, R.; Johanson, I. A.; Allen, R. M.

2014-10-01

54

Early Introduction of Everolimus Immunosuppressive Regimen in Liver Transplantation with Extra-Anatomic Aortoiliac-Hepatic Arterial Graft Anastomosis  

PubMed Central

Liver transplantation is the treatment of choice for patients with acute and chronic end-stage liver disease, when no other medical treatment is possible. Despite high rates of 1- to 5-year survival, long-term adverse effects of immunosuppressant agents remain of major concern. Current research and clinical efforts are made to develop immunosuppressant agents that minimize adverse effects along with a low rate of graft rejection. Tailoring immunosuppressive therapy to individual patients by the use of proliferation signal inhibitors seems to be the best way to minimize toxicity and increase efficacy. Recently everolimus has been introduced in clinical practice; among its adverse effects an increased incidence of arterial graft thrombosis in renal transplants, vascular anastomosis leakage, impaired wound healing, and thrombotic microangiopathy have been reported. We present the case of a 54-year-old patient submitted to liver transplantation for end-stage liver disease treated by an extra-anatomic aortoiliac-hepatic arterial graft anastomosis and early postoperative introduction of everolimus for acute renal failure. Postoperative period was characterized by two abdominal collections and reactivation of cytomegalovirus infection that were treated by percutaneous drainage and antiviral therapy, respectively; the patient is well after 8-month followup with patency of the arterial conduit and no leakage. PMID:25309771

Felli, Emanuele; Vennarecci, Giovanni; Colasanti, Marco; Santoro, Roberto; de Werra, Edoardo; Scotti, Andrea; Burocchi, Mirco; Levi Sandri, Giovanni B.; Campanelli, Alessandra; Lepiane, Pasquale; Ettorre, Giuseppe M.

2014-01-01

55

Splenic Artery Transposition Graft Usage for the Supply of the Right Hepatic Artery: A Case Report  

PubMed Central

Hepatic artery aneurysms are responsible for 12% to 20% of all visceral arterial aneurysms. Because most patients are asymptomatic, this disease is generally diagnosed incidentally during radiologic examination. Aneurysm rupture develops in 14% to 80% of cases, depending on the aneurysmatic segment's diameter and location, as well as other etiologic factors. Mortality rates associated with rupture range between 20% and 70%. Thus, early diagnosis and timely initiation of medical interventions are critical to improve survival rates. Here, we present a male patient, age 69 years, with a hepatic artery aneurysm that was detected incidentally. The 3-cm aneurysm was detected on contrast-enhanced computed tomography and extended from the common hepatic artery to the hepatic trifurcation. A laparotomy was performed using a right subcostal incision. After dissection of the hepatoduodenal ligament, the common, right, and left hepatic arteries, as well as the gastroduodenal artery, were suspended separately. Then, the aneurysmatic hepatic artery segment was resected, and the gastroduodenal artery stump was ligated. An end-to-end anastomosis was formed between the left and common hepatic arteries, followed by an end-to-end anastomosis formed between the right hepatic artery and splenic artery using a splenic artery transposition graft. Postoperative follow-up examinations showed that both hepatic arterial circulations were good, and no splenic infraction had developed. PMID:23971784

Odabasi, Mehmet; Eris, Cengiz; Yildiz, Mehmet Kamil; Abuoglu, Hasan; Akbulut, Sami; Saglam, Abdullah

2013-01-01

56

Automated quantification of carotid artery stenosis on contrast-enhanced MRA data using a deformable vascular tube model.  

PubMed

The purpose of this study was to develop and validate a method for automated segmentation of the carotid artery lumen from volumetric MR Angiographic (MRA) images using a deformable tubular 3D Non-Uniform Rational B-Splines (NURBS) model. A flexible 3D tubular NURBS model was designed to delineate the carotid arterial lumen. User interaction was allowed to guide the model by placement of forbidden areas. Contrast-enhanced MRA (CE-MRA) from 21 patients with carotid atherosclerotic disease were included in this study. The validation was performed against expert drawn contours on multi-planar reformatted image slices perpendicular to the artery. Excellent linear correlations were found on cross-sectional area measurement (r = 0.98, P < 0.05) and on luminal diameter (r = 0.98, P < 0.05). Strong match in terms of the Dice similarity indices were achieved: 0.95 ± 0.02 (common carotid artery), 0.90 ± 0.07 (internal carotid artery), 0.87 ± 0.07 (external carotid artery), 0.88 ± 0.09 (carotid bifurcation) and 0.75 ± 0.20 (stenosed segments). Slight overestimation of stenosis grading by the automated method was observed. The mean differences was 7.20% (SD = 21.00%) and 5.2% (SD = 21.96%) when validated against two observers. Reproducibility in stenosis grade calculation by the automated method was high; the mean difference between two repeated analyses was 1.9 ± 7.3%. In conclusion, the automated method shows high potential for clinical application in the analysis of CE-MRA of carotid arteries. PMID:22160666

Suinesiaputra, Avan; de Koning, Patrick J H; Zudilova-Seinstra, Elena; Reiber, Johan H C; van der Geest, Rob J

2012-08-01

57

Low-dose psoralen and UVA (PUVA) therapy-enhanced arterial shrinkage after balloon angioplasty in rabbits  

NASA Astrophysics Data System (ADS)

Restenosis after balloon angioplasty is caused by both intimal hyperplasia and arterial shrinkage (constrictive remodeling). Previous studies have indicated the inhibitory effect of photodynamic therapy on intimal hyperplasia development after angioplasty. The potential of a photoactivation regime (Psoralen + UVA irradiation: PUVA), which does not cause unwanted systemic side effects, for the prevention of both intimal hyperplasia formation and constrictive remodeling following balloon dilation was explored in the present study. In the rabbit iliac artery, balloon dilation followed by PUVA- therapy at a radiant exposure of 1 J/cm2 was performed (n equals 10). Control balloon dilation was performed in the contralateral arteries (n equals 10). After 4 weeks of survival, angiographic lumen renarrowing was determined in terms of intimal hyperplasia and constrictive remodeling. Late loss, but not intimal hyperplasia, was significantly larger in the PUVA group as compared to the control group (p less than 0.05). This difference in angiographic lumen loss can only be attributed to the difference in constrictive remodeling (arterial shrinkage). Thus, PUVA-therapy did not prevent intimal hyperplasia following balloon dilation. PUVA-therapy even enhanced luminal narrowing by augmented constrictive arterial remodeling.

Perree, Jop; van Leeuwen, Ton G. J. M.; Velema, Evelyn; Borst, Cornelius

1998-07-01

58

ACE inhibition enhances bradykinin relaxations through nitric oxide and B1 receptor activation in bovine coronary arteries.  

PubMed

Bradykinin causes vascular relaxations through release of endothelial relaxing factors including prostacyclin, nitric oxide (NO) and epoxyeicosatrienoic acids (EETs). Bradykinin is metabolized by angiotensin converting enzyme (ACE) and ACE inhibition enhances bradykinin relaxations. Our goal was to characterize the role of bradykinin receptors and endothelial factors in ACE inhibitor-enhanced relaxations in bovine coronary arteries. In U46619 preconstricted arteries, bradykinin (10-11-10-8m) caused concentration-dependent relaxations (maximal relaxation ?100%, log EC50=-9.8±0.1). In the presence of the NO synthase inhibitor, N-nitro-L-arginine (L-NA, 30 ?m) and the cyclooxygenase inhibitor, indomethacin (10 ?m), relaxations were reduced by an inhibitor of EET synthesis, miconazole (10 ?m) (maximal relaxation=55±10%). Bradykinin relaxations were inhibited by the bradykinin 2 (B2) receptor antagonist, D-Arg0-Hyp3-Thi5,8-D-Phe7-bradykinin (1 ?m) (log EC50=-8.5±0.1) but not altered by the B1 receptor antagonist, des-Arg9[Leu8]bradykinin (1 ?m). Mass spectrometric analysis of bovine coronary artery bradykinin metabolites revealed a time-dependent increase in bradykinin (1-5) and (1-7) suggesting metabolism by ACE. ACE inhibition with captopril (50 ?m) enhanced bradykinin relaxations (log EC50=-10.3±0.1). The enhanced relaxations were eliminated by L-NA or the B1 receptor antagonist but not the B2 receptor antagonist. Our results demonstrate that ACE inhibitor-enhanced bradykinin relaxations of bovine coronary arteries occur through endothelial cell B1 receptor activation and NO. PMID:23729620

Gauthier, Kathryn M; Cepura, Cody J; Campbell, William B

2013-09-01

59

Uterine artery blood flow characteristics assessed during oestrus and the early luteal phase of pregnant and non-pregnant bitches.  

PubMed

The aim of this study was to measure uterine artery blood velocity daily using Doppler ultrasonography in 10 young and 10 older clinically normal bitches throughout oestrus. Typical arterial waveforms identified in young bitches were characterised by a systolic peak and subsequent flow throughout diastole, whereas in older bitches, flow was sometimes absent in diastole. For 3 days immediately prior to ovulation, at the time of declining plasma oestrogen and increasing progesterone concentrations, resistance index (RI) increased, principally associated with decreased diastolic velocity; in some bitches there was absent late diastolic flow during this time. In older bitches, the waveform appearance was more variable, with absent late and early diastolic flow observed in some cases. Mean RI was higher throughout oestrus for older bitches compared with young bitches, although both groups had a similar 3-day duration increase before ovulation. Nine of the young bitches and five of the older bitches became pregnant; litter size was smaller for the older bitches. Non-pregnant bitches: (1) were significantly older; (2) had fewer waveforms with continuous diastolic flow 2 days before ovulation; (3) had lower end diastolic velocity, higher RI and fewer waveforms with continuous diastolic flow 2 days after ovulation, and (4) had lower plasma progesterone concentrations 5 days after ovulation. These are the first detailed observations of uterine artery blood velocity and waveform appearance throughout oestrus in bitches, and this is the first description of a link between impaired diastolic flow and reduced fertility. Assessment of uterine artery velocity could be useful to promote understanding of physiological mechanisms and could also become an important tool to assess potential infertility. PMID:23770397

Freeman, S L; Russo, M; England, G C W

2013-08-01

60

Early and late response-to-injury in patients undergoing transradial coronary angiography: arterial remodeling in smokers  

PubMed Central

Objectives: To investigate the effect of smoking on vascular response to transradial coronary angiography (TCA). Background: Cigarette smoking is the most important modifiable cardiovascular risk factor associated with endothelial dysfunction. Methods: Radial artery flow-mediated vasodilation (RA-FMD), local stiffness (fractional diameter change), intima-media thickness (IMT), luminal and external arterial diameter were measured in 40 current smokers (CS) and former smokers (FS) at 6-14 months at the site of previous TCA and contralateral control artery. Vascular regenerative capacity was studied as chemotactic cell migration in vitro and ex vivo (n=10) and the time course of endothelial functional recovery following RA-FMD up to 72 h after TCA (n=10). Results: At 10 ± 3 months after TCA, subjects exhibited significant local stiffening and increased IMT as compared to the control arm. These late structural changes were significantly more pronounced in CS as compared to FS. IMT thickening correlated with packyears, number of daily cigarettes, and inversely with RA-FMD. Nitric oxide synthase (NOS)-dependent chemotaxis of CS’ circulating angiogenic cells was impaired. Ex vivo incubation of endothelial cells with CS’ plasma inhibited NOS-dependent endothelial wound closure and chemotaxis. In vivo, TCA acutely decreased RA-FMD. At 24 h, RA-FMD had recovered in FS but remained impaired at 24 h and only recovered at 48 h in CS. Conclusion: In active smokers, transradial coronary angiography is associated with delayed early recovery from transient endothelial dysfunction, decreased NOS-dependent vascular regeneration, and late arterial remodeling pointing towards potential harmful effects of transradial coronary angiography on vascular function in distinct subsets of patients. PMID:25006532

Sansone, Roberto; Stegemann, Emilia; Özaslan, Göksen; Schuler, Dominik; Lukosz, Margarete; Rodriguez-Mateos, Ana; Lauer, Thomas; Westenfeld, Ralf; Kelm, Malte; Heiss, Christian

2014-01-01

61

Genetic polymorphisms associated with carotid artery intima-media thickness and coronary artery calcification in women of the Kronos Early Estrogen Prevention Study  

PubMed Central

Menopausal hormone treatment (MHT) may limit progression of cardiovascular disease (CVD) but poses a thrombosis risk. To test targeted candidate gene variation for association with subclinical CVD defined by carotid artery intima-media thickness (CIMT) and coronary artery calcification (CAC), 610 women participating in the Kronos Early Estrogen Prevention Study (KEEPS), a clinical trial of MHT to prevent progression of CVD, were genotyped for 13,229 single nucleotide polymorphisms (SNPs) within 764 genes from anticoagulant, procoagulant, fibrinolytic, or innate immunity pathways. According to linear regression, proportion of European ancestry correlated negatively, but age at enrollment and pulse pressure correlated positively with CIMT. Adjusting for these variables, two SNPs, one on chromosome 2 for MAP4K4 gene (rs2236935, ? = 0.037, P value = 2.36 × 10?06) and one on chromosome 5 for IL5 gene (rs739318, ? = 0.051, P value = 5.02 × 10?05), associated positively with CIMT; two SNPs on chromosome 17 for CCL5 (rs4796119, ? = ?0.043, P value = 3.59 × 10?05; rs2291299, ? = ?0.032, P value = 5.59 × 10?05) correlated negatively with CIMT; only rs2236935 remained significant after correcting for multiple testing. Using logistic regression, when we adjusted for waist circumference, two SNPs (rs11465886, IRAK2, chromosome 3, OR = 3.91, P value = 1.10 × 10?04; and rs17751769, SERPINA1, chromosome 14, OR = 1.96, P value = 2.42 × 10?04) associated positively with a CAC score of >0 Agatston unit; one SNP (rs630014, ABO, OR = 0.51, P value = 2.51 × 10?04) associated negatively; none remained significant after correcting for multiple testing. Whether these SNPs associate with CIMT and CAC in women randomized to MHT remains to be determined. PMID:23188791

Petterson, Tanya M.; Jeavons, Elysia N.; Lnu, Abhinita S.; Rider, David N.; Heit, John A.; Cunningham, Julie M.; Huggins, Gordon S.; Hodis, Howard N.; Budoff, Matthew J.; Santoro, Nanette; Hopkins, Paul N.; Lobo, Rogerio A.; Manson, JoAnn E.; Naftolin, Frederick; Taylor, Hugh S.; Harman, S. Mitchell; de Andrade, Mariza

2013-01-01

62

Effect of early exercise engagement on arterial stiffness in patients diagnosed with a transient ischaemic attack.  

PubMed

This study investigated the effects of regular exercise participation on common carotid artery stiffness in patients recently diagnosed with transient ischaemic attack (TIA). A total of 21 male and 4 female participants (mean±s.d.; 66±12 years, 1.72±0.07?m, 85.5±12.4?kg), recruited within 2 weeks of TIA diagnosis, completed a risk stratification assessment (including fasting blood glucose, cholesterol), a health history questionnaire and underwent measures of arterial stiffness (compliance and distensibility). Participants were then randomized to either an exercise (EX; 8-week intervention) or a usual-care control (CON) condition. Identical measures were obtained post intervention. Within-subject, repeated measures analysis of variance, with Condition as the between-subject factor (EX and CON), was used to assess measures of arterial stiffness at the baseline and postintervention assessment. Results revealed a significant interaction whereby an increase in compliance (0.71±0.24 vs 0.83±0.28?mm(2)?kPa(-1), P=0.048, partial ?(2)=0.159) and distensibility (15.98±5.95 vs 19.49±6.60 10(-3)?kPa(-1), P=0.023, partial ?(2)=0.204) was observed for EX but not for CON. The present study has demonstrated that engagement in exercise soon after TIA diagnosis leads to improved large artery health. These improvements in vascular health may reduce the risk of an ensuing or recurring cardio- or cerebrovascular event. PMID:24990421

Woolley, B; Stoner, L; Lark, S; Wong, L; Lanford, J; Faulkner, J

2015-02-01

63

Maternal alcohol consumption in pregnancy enhances arterial stiffness and alters vasodilator function that varies between vascular beds in fetal sheep.  

PubMed

While the impact of alcohol consumption by pregnant women on fetal neurodevelopment has received much attention, the effects on the cardiovascular system are not well understood. We hypothesised that repeated exposure to alcohol (ethanol) in utero would alter fetal arterial reactivity and wall stiffness, key mechanisms leading to cardiovascular disease in adulthood. Ethanol (0.75 g (kg body weight)(-1)) was infused intravenously into ewes over 1 h daily for 39 days in late pregnancy (days 95-133 of pregnancy, term ?147 days). Maternal and fetal plasma ethanol concentrations at the end of the hour were ?115 mg dl(-1), and then declined to apparent zero over 8 h. At necropsy (day 134), fetal body weight and fetal brain-body weight ratio were not affected by alcohol infusion. Small arteries (250-300 ?m outside diameter) from coronary, renal, mesenteric, femoral (psoas) and cerebral beds were isolated. Endothelium-dependent vasodilatation sensitivity was reduced 10-fold in coronary resistance arteries, associated with a reduction in endothelial nitric oxide synthase mRNA (P = 0.008). Conversely, vasodilatation sensitivity was enhanced 10-fold in mesenteric and renal resistance arteries. Arterial stiffness was markedly increased (P = 0.0001) in all five vascular beds associated with an increase in elastic modulus and, in cerebral vessels, with an increase in collagen I? mRNA. Thus, we show for the first time that fetal arteries undergo marked and regionally variable adaptations as a consequence of repeated alcohol exposure. These alcohol-induced vascular effects occurred in the apparent absence of fetal physical abnormalities or fetal growth restriction. PMID:24756643

Parkington, Helena C; Kenna, Kelly R; Sozo, Foula; Coleman, Harold A; Bocking, Alan; Brien, James F; Harding, Richard; Walker, David W; Morley, Ruth; Tare, Marianne

2014-06-15

64

Enhanced coronary vasoconstrictor responses to 5-hydroxytryptamine in the presence of a coronary artery stenosis in anaesthetized dogs.  

PubMed Central

1. In the anaesthetized dog, left circumflex coronary artery blood flow and external diameter were measured and the vascular responses to an injection of 5-hydroxytryptamine (5-HT, 0.02-2 micrograms kg-1) assessed, before and after a screw clamp had been placed on the artery to produce a severe stenosis. 2. In the normal coronary circulation, intra-coronary (i.c.) injection of 5-HT increased coronary blood flow (CBF) but decreased the external diameter of the large coronary artery (CD), without affecting systemic mean arterial pressure or heart rate. 3. In the normal coronary circulation, the 5-HT-induced increases in CBF were unaffected by blockade of 5-HT2-receptors with ketanserin (0.1 mg kg-1 i.c.) but were significantly attenuated by blockade of 5-HT1-like receptors with methysergide (0.1 mg kg-1 i.c.). 4. In the presence of a severe stenosis, the increase in CBF produced by 5-HT was markedly attenuated and a secondary decrease in CBF was revealed. The stenosis also caused a marked enhancement of the 5-HT-induced constriction of the large artery, such that the reduction of the CD was approximately doubled at all doses of 5-HT tested. The enhanced 5-HT-induced reduction in CD was similar with placement of the stenosis either proximal or distal to the site of diameter measurement. 5. In the presence of the stenosis, blockade of 5-HT 2-receptors with ketanserin (0.1 mg kg-1 i.c.) significantly attenuated the 5-HT-induced decreases in CD and CBF.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2372656

Woodman, O. L.

1990-01-01

65

Early and Midterm Outcome of Redo Coronary Artery Bypass Grafting: On-Pump versus Off-Pump Bypass  

PubMed Central

Background Redo coronary artery bypass grafting (CABG) is still associated with increased morbidity and mortality as compared to the first-time operation. Further, the application of the off-pump technique to redo CABG is limited due to technical difficulties. The aim of this retrospective study was to analyze early and midterm results after redo CABG and compare the outcome of redo on-pump and off-pump CABG. Methods From June 1996 to October 2011, elective redo CABG was performed in 32 patients. Mean age was 64.8 years (on pump 64.3 years vs. off pump 65.5 years; p=0.658), and 21 patients were male. Among these patients, 14 (43.8%) underwent on-pump CABG, and 18 (56.2%) underwent off-pump CABG. Results Internal thoracic artery was used in 22 patients (68.8%), and total arterial revascularization was achieved in 17 patients (53.1%). The average number of distal anastomoses was 2.13, and the rate of incomplete revascularization was 43.8%. The rate of total arterial revascularization was higher in the off-pump group (14.3% vs. 83.3%, p<0.001), and the use of saphenous vein graft was more in the on-pump group (78.6% vs. 16.7%, p<0.001). Overall hospital mortality was 3.1% (n=1) and was comparable in both groups (on pump 7.1% vs. off pump 0%; p=0.249). Postoperative complications occurred in 9 patients (64.2%), and the rate of complications was high in the on-pump group without statistical significance (64.2% vs. 33.3%, p=0.082). The mean follow-up duration was 5.4 years, and overall survival at 10 years was 86.0%±10.5%. There was no significant difference in the 10-year survival rate between the two groups (79.6% vs. 100%, p=0.225). Conclusion Redo CABG can be safely performed with acceptable mortality. Redo off-pump coronary artery bypass is feasible with low mortality and morbidity, comparable target vessel bypass grafting, and long-term survival. The off-pump technique might be considered a safe option for redo CABG in high-risk patients. PMID:25207219

Shin, Yu Rim; Lee, Sak; Joo, Hyun Chel; Youn, Young-Nam; Kim, Jong Gun; Yoo, Kyung-Jong

2014-01-01

66

Resistance to erythropoiesis-stimulating agents is associated with arterial microcalcification in early hemodialysis patients.  

PubMed

The aim of this study was to evaluate the relationship between arterial microcalcification (AMiC) and erythropoiesis-stimulating agents (ESA) hyporesponsiveness in hemodialysis patients. The presence of AMiC was confirmed by pathologic examination of von Kossa-stained arterial specimens acquired during vascular access surgery. We assessed the ESA hyporesponsiveness index (EHRI), defined as the weekly ESA dose per kilogram body weight divided by the hemoglobin level. AMiC was detected in 33 (40.2%) of 82 patients. Patients with diabetes had a higher incidence of AMiC than patients without diabetes. The serum levels of albumin and cholesterol were higher in patients without AMiC than in patients with AMiC. The serum levels of intact parathyroid hormone were lower in patients with AMiC than in patients without AMiC. The serum levels of phosphate and calcium-phosphorus product did not differ between the two groups. The mean EHRI value was higher in patients with AMiC than in patients without AMiC. In multivariate analyses, ESA hyporesponsiveness and diabetes showed a significant association with AMiC. In conclusion, ESA hyporesponsiveness may be a clinical relevant parameters related to AMiC in hemodialysis patients. PMID:24772434

Won, Hye Sung; Choi, Su Jin; Yun, Yu Seon; Shin, Ok-Ran; Ko, Yoon Ho; Kim, Young Soo; Yoon, Sun Ae; Kim, Young Ok

2014-01-01

67

Vasodilatation of multiple cerebral arteries in early stage of stroke-like episode with MELAS.  

PubMed

We describe a patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), with multiple cerebral vasodilatations in a stroke-like episode visualised by using magnetic resonance angiography (MRA) and CT angiography (CTA). In the acute stroke-like episode stage, T2-weighted and fluid-attenuated inversion recovery MRI showed high-intensity areas in the left occipital area. In addition, MRA and CTA revealed prominent dilatation of the left posterior cerebral artery and temporal branches of the middle cerebral artery with focal hyperperfusions using CT perfusion (CTP) that corresponded to the MRI. After 10days, with the development of aphasia, MRI indicated the lesions had spread to the temporal and parietal regions, and this distribution was not confined to major vascular territories. The patient's symptoms gradually improved, accompanied by the attenuation of MRI, CTA, and CTP findings. These characteristic features along with the MRI changes that spread beyond vascular boundaries and the multiple cerebral vasodilatations prior to the development of clinical symptoms are not fully explained by the mitochondrial angiopathy or cytopathy theories. These findings provide further evidence supporting neuronal hyperexcitability in stroke-like episodes of MELAS. PMID:25128282

Minobe, Shoko; Matsuda, Akiko; Mitsuhashi, Tetsuya; Ishikawa, Motonao; Nishimura, Yoshiko; Shibata, Koichi; Ito, Eiichi; Goto, Yu-Ichi; Nakaoka, Takashi; Sakura, Hiroshi

2015-02-01

68

Resistance to Erythropoiesis-Stimulating Agents Is Associated with Arterial Microcalcification in Early Hemodialysis Patients  

PubMed Central

The aim of this study was to evaluate the relationship between arterial microcalcification (AMiC) and erythropoiesis-stimulating agents (ESA) hyporesponsiveness in hemodialysis patients. The presence of AMiC was confirmed by pathologic examination of von Kossa-stained arterial specimens acquired during vascular access surgery. We assessed the ESA hyporesponsiveness index (EHRI), defined as the weekly ESA dose per kilogram body weight divided by the hemoglobin level. AMiC was detected in 33 (40.2%) of 82 patients. Patients with diabetes had a higher incidence of AMiC than patients without diabetes. The serum levels of albumin and cholesterol were higher in patients without AMiC than in patients with AMiC. The serum levels of intact parathyroid hormone were lower in patients with AMiC than in patients without AMiC. The serum levels of phosphate and calcium-phosphorus product did not differ between the two groups. The mean EHRI value was higher in patients with AMiC than in patients without AMiC. In multivariate analyses, ESA hyporesponsiveness and diabetes showed a significant association with AMiC. In conclusion, ESA hyporesponsiveness may be a clinical relevant parameters related to AMiC in hemodialysis patients. PMID:24772434

Won, Hye Sung; Choi, Su Jin; Yun, Yu Seon; Shin, Ok-Ran; Ko, Yoon Ho; Kim, Young Soo; Yoon, Sun Ae; Kim, Young Ok

2014-01-01

69

Enhanced External Counterpulsation Improves Peripheral Artery Flow Mediated Dilation in Patients With Chronic Angina: A Randomized Sham-Controlled Study  

PubMed Central

Background Mechanisms responsible for anti-ischemic benefits of enhanced external counterpulsation (EECP) remain unknown. This was the first randomized, sham controlled study to investigate the extra-cardiac effects of EECP on peripheral artery flow mediated dilation. Methods and Results Forty-two symptomatic patients with coronary artery disease (CAD) were randomized (2:1 ratio) to either 35 1-hr sessions of EECP (n=28) or Sham-EECP (n=14). Flow-mediated dilation of the brachial and femoral arteries was performed using ultrasound. Plasma levels of nitrate and nitrite (NOx), 6-keto prostaglandin F1? (PGF1?), endothelin-1 (ET-1), asymmetric dimethylarginine (ADMA), tumor necrosis factor–? (TNF-?), monocyte chemoattractant protein–1 (MCP-1), vascular cell adhesion molecule (sVCAM), C-reactive protein (hsCRP), and 8-Isoprostane (8-iso-PGF2?) were measured. EECP increased brachial (+51% vs. +2%) and femoral (+30% vs. +3%) artery flow mediated dilation, the nitric oxide turnover/production marker NOx (+36% vs. +2%) and PGF1? (+71% vs. +1%), while decreasing ET-1 (-25% vs. +5%) and the nitric oxide synthase inhibitor ADMA (-28% vs. +0.2%) in treatment vs. sham, respectively (all p<0.05). EECP decreased the pro-inflammatory cytokines TNF-? (-16% vs. +12%), MCP-1 (-13% vs. +0.2%), sVCAM-1 (-6% vs. +1%), hsCRP (-32% vs. +5%), and the lipid peroxidation marker 8-iso-PGF2? (-21% vs. +1.3%) in treatment vs. sham, respectively (all p<0.05). EECP reduced angina classification (-62% vs 0%; p<0.001) in treatment vs. sham, respectively. Conclusions Our findings provide novel mechanistic evidence that EECP has a beneficial effect on peripheral artery flow mediated dilation and endothelial-derived vasoactive agents in patients with symptomatic CAD. PMID:20921442

Braith, Randy W.; Conti, C. Richard; Nichols, Wilmer W.; Choi, Calvin Y.; Khuddus, Matheen A.; Beck, Darren T.; Casey, Darren P.

2010-01-01

70

Regional Ischemia and Ischemic Injury in Patients With Acute Middle Cerebral Artery Stroke as Defined by Early Diffusion-Weighted and Perfusion-Weighted MRI  

Microsoft Academic Search

Background and Purpose—We sought to map early regional ischemia and infarction in patients with middle cerebral artery (MCA) stroke and compare them with final infarct size using advanced MRI techniques. MRI can now delineate very early infarction by diffusion-weighted imaging (DWI) and abnormal tissue perfusion by perfusion-weighted imaging (PWI). Methods—Seventeen patients seen within 12 hours of onset of MCA stroke

Guy Rordorf; Walter J. Koroshetz; William A. Copen; Steven C. Cramer; Pamela W. Schaefer; Ronald F. Budzik; Lee H. Schwamm; Ferdinando Buonanno; A. Gregory Sorensen; Gilberto Gonzalez

71

Early experience of Cued Speech enhances speechreading performance in deaf.  

PubMed

It is known that deaf individuals usually outperform normal hearing subjects in speechreading; however, the underlying reasons remain unclear. In the present study, speechreading performance was assessed in normal hearing participants (NH), deaf participants who had been exposed to the Cued Speech (CS) system early and intensively, and deaf participants exposed to oral language without Cued Speech (NCS). Results show a gradation in performance with highest performance in CS, then in NCS, and finally NH participants. Moreover, error analysis suggests that speechreading processing is more accurate in the CS group than in the other groups. Given that early and intensive CS has been shown to promote development of accurate phonological processing, we propose that the higher speechreading results in Cued Speech users are linked to a better capacity in phonological decoding of visual articulators. PMID:21995589

Aparicio, Mario; Peigneux, Philippe; Charlier, Brigitte; Neyrat, Charlotte; Leybaert, Jacqueline

2012-02-01

72

Progesterone implants enhance SIV vaginal transmission and early virus load.  

PubMed

Simian immunodeficiency virus (SIV) can cross the intact vaginal epithelium to establish a systemic infection in macaques (mac). Using this SIVmac model, we found that subcutaneous progesterone implants, which could mimic hormonally based contraceptives, thinned the vaginal epithelium and enhanced SIV vaginal transmission 7.7-fold over that observed in macaques treated with placebo implants and exposed to SIV in the follicular phase of the menstrual cycle. Progesterone treatment also increased the number of SIV DNA-positive cells in the vaginal lamina propria as detected by in situ polymerase chain reaction analysis. Moreover, plasma viral RNA was elevated for the first three months in macaques with progesterone implants, and three of the progesterone-treated macaques developed relatively rapid disease courses. This study shows that SIV genital infection and disease course are enhanced by subcutaneous implants containing progesterone when compared with the rate of vaginal transmission in the follicular phase. PMID:8837605

Marx, P A; Spira, A I; Gettie, A; Dailey, P J; Veazey, R S; Lackner, A A; Mahoney, C J; Miller, C J; Claypool, L E; Ho, D D; Alexander, N J

1996-10-01

73

Early induction of secondary vortices for micromixing enhancement  

Microsoft Academic Search

In the present work a new type of micromixer has been proposed and its mixing characteristic has been analyzed. The micromixer\\u000a can be viewed as a U-tube with a side inlet. Here micromixing is enhanced by the secondary vortex generation induced by the\\u000a curvature of the tube. The flow in the mixer geometry is investigated theoretically to understand micro-mixing using

Ankur Gigras; S. Pushpavanam

2008-01-01

74

Chlorogenic Acid Enhances Abdominal Skin Flap Survival Based on Epigastric Artery in Nondiabetic and Diabetic Rats.  

PubMed

Previous studies showed that chlorogenic acid (CGA) accelerates wound healing via its antioxidant activity. We aimed to investigate the effect of CGA in an experimental epigastric abdominal skin flap model in nondiabetic and diabetic rats. Rats were firstly divided into 2 groups: nondiabetic and diabetic. Diabetes was induced by streptozotocin. Then, 4 subgroups were created for each group: vehicle as well as 0.2 mg/0.5 mL, 1 mg/0.5 mL, and 5 mg/0.5 mL CGA treatments. Right epigastric artery-based abdominal skin flaps were elevated and sutured back into their original position. Chlorogenic acid or vehicle was injected once into the femoral arteries by leaving the epigastric artery as the single artery feeding the flaps during the injection. On postoperative day 7, flap survivals were evaluated, and the rats were killed. Distal flap tissues were collected for histopathological and biochemical assays. Chlorogenic acid showed greater flap survival in both nondiabetic and diabetic rats. Capillary density was increased, and necrosis was reduced in the CGA-treated rats. Chlorogenic acid decreased malondialdehyde levels as well as increased reduced glutathione and superoxide dismutase levels in the flap tissues. This study showed that CGA significantly improved flap survival by its antioxidant activities with intra-arterial local injections. PMID:25356637

Bagdas, Deniz; Etoz, Betul Cam; Gul, Zulfiye; Ozyigit, Musa Ozgur; Cinkilic, Nilufer; Inan, Sevda; Buyukcoskun, Naciye Isbil; Ozluk, Kasim; Gurun, Mine Sibel

2014-10-28

75

Nitrogen-enhanced greenhouse warming on early Earth  

NASA Astrophysics Data System (ADS)

Early in Earth's history, the Sun provided less energy to the Earth than it does today. However, the Earth was not permanently glaciated, an apparent contradiction known as the faint young Sun paradox. By implication, the Earth must have been warmed by a stronger greenhouse effect or a lower planetary albedo. Here we use a radiative-convective climate model to show that more N2 in the atmosphere would have increased the warming effect of existing greenhouse gases by broadening their absorption lines. With the atmospheric CO2 and CH4 levels estimated for 2.5billion years ago, a doubling of the present atmospheric nitrogen (PAN) level would cause a warming of 4.4?C. Our new budget of Earth's geological nitrogen reservoirs indicates that there is a sufficient quantity of nitrogen in the crust (0.5 PAN) and mantle (>1.4 PAN) to have supported this, and that this nitrogen was previously in the atmosphere. In the mantle, N correlates with 40Ar, the daughter product of 40K, indicating that the source of mantle N is subducted crustal rocks in which NH4+ has been substituted for K+. We thus conclude that a higher nitrogen level probably helped warm the early Earth, and suggest that the effects of N2 should be considered in assessing the habitable zone for terrestrial planets.

Goldblatt, Colin; Claire, Mark W.; Lenton, Timothy M.; Matthews, Adrian J.; Watson, Andrew J.; Zahnle, Kevin J.

2009-12-01

76

Effects of Re-Arterialization on Early Graft Function and Regeneration in the Rat Model of Heterotopic Auxiliary Liver Transplantation  

Microsoft Academic Search

In the rat model of heterotopic auxiliary liver transplantation, graft re-arterialization may influence the outcome of inter-liver competition. This was investigated in the current study using two transplanted groups with or without graft re-arterialization. Immediately after reperfusion, the re-arterialized grafts showed significantly higher bile flow rate and bilirubin excretion than the grafts without re-arterialization. DNA synthesis rate was also increased

Y.-D. Fan; M. Praet; B. Vanzieleghem; D. Vanwynsberghe; D. Stoop; G. Leroux-Roels; J. Delanghe; B. de Hemptinne

2000-01-01

77

Two functional polymorphisms of ROCK2 enhance arterial stiffening through inhibiting its activity and expression.  

PubMed

Derangement of Rho-associated kinases (ROCKs) has been related to coronary artery disease and stroke. ROCK2, rather than ROCK1, plays a predominant role in vascular contractility. The present study aims to test (1) the associations between ROCK2 single nucleotide polymorphisms (SNPs) and arterial stiffness, and (2) the molecular mechanism accounting for their effects. Stiffness parameters including beta (?), elasticity modulus (Ep) and pulse wave velocity (PWV) were obtained by carotid ultrasonography. Seven tagging SNPs of ROCK2 were initially genotyped in 856 subjects and significant SNPs were replicated in another group of 527 subjects. Two SNPs in complete linkage disequilibrium were found to be significantly associated with arterial stiffness. The major alleles of rs978906 (A allele) and rs9808232 (C allele) were associated with stiffer arteries. SNP rs978906 was predicted to influence microRNA(miR)-1183 binding to ROCK2, while rs9808232 causes amino acid substitution. To determine their functional impact, plasmid constructs carrying different alleles of the significant SNPs were created. Compared to rs978906G-allele constructs, cells transfected with rs978906A-allele constructs had higher baseline luciferase activities and were less responsive to miR-1183 changes. Oxidized-low density lipoprotein (Ox-LDL) suppressed miR-1183 levels and increased ROCK2 protein amounts. For rs9808232, cells transfected with C-allele constructs had significantly higher ROCK activities than those with A-allele constructs. Leukocyte ROCK activities were further measured in 52 healthy subjects. The average ROCK activity was highest in human subjects with CC genotype at rs9808232, followed by those with AC and lowest in AA. Taken together, the present study showed that two functional SNPs of ROCK2 increase susceptibility of arterial stiffness in the Chinese population. Non-synonymous SNP rs9808232 influences ROCK2 activity, while 3' UTR SNP rs978906 affects the ROCK2 protein synthesis by interfering miR-1183 binding. PMID:25481646

Liao, Yi-Chu; Liu, Ping-Yen; Lin, Hsiu-Fen; Lin, Wen-Yi; Liao, James K; Juo, Suh-Hang H

2015-02-01

78

Early Postnatal EEG Features of Perinatal Arterial Ischaemic Stroke with Seizures  

PubMed Central

Background Stroke is the second most common cause of seizures in term neonates and is associated with abnormal long-term neurodevelopmental outcome in some cases. Objective To aid diagnosis earlier in the postnatal period, our aim was to describe the characteristic EEG patterns in term neonates with perinatal arterial ischaemic stroke (PAIS) seizures. Design Retrospective observational study. Patients Neonates >37 weeks born between 2003 and 2011 in two hospitals. Method Continuous multichannel video-EEG was used to analyze the background patterns and characteristics of seizures. Each EEG was assessed for continuity, symmetry, characteristic features and sleep cycling; morphology of electrographic seizures was also examined. Each seizure was categorized as electrographic-only or electroclinical; the percentage of seizure events for each seizure type was also summarized. Results Nine neonates with PAIS seizures and EEG monitoring were identified. While EEG continuity was present in all cases, the background pattern showed suppression over the infarcted side; this was quite marked (>50% amplitude reduction) when the lesion was large. Characteristic unilateral bursts of theta activity with sharp or spike waves intermixed were seen in all cases. Sleep cycling was generally present but was more disturbed over the infarcted side. Seizures demonstrated a characteristic pattern; focal sharp waves/spike-polyspikes were seen at frequency of 1–2 Hz and phase reversal over the central region was common. Electrographic-only seizure events were more frequent compared to electroclinical seizure events (78 vs 22%). Conclusions Focal electrographic and electroclinical seizures with ipsilateral suppression of the background activity and focal sharp waves are strong indicators of PAIS. Approximately 80% of seizure events were the result of clinically unsuspected seizures in neonates with PAIS. Prolonged and continuous multichannel video-EEG monitoring is advocated for adequate seizure surveillance. PMID:25051161

Low, Evonne; Mathieson, Sean R.; Stevenson, Nathan J.; Livingstone, Vicki; Ryan, C. Anthony; Bogue, Conor O.; Rennie, Janet M.; Boylan, Geraldine B.

2014-01-01

79

Hypoxia-induced 15-HETE enhances the constriction of internal carotid arteries by down-regulating potassium channels.  

PubMed

Severe hypoxia induces the constriction of internal carotid arteries (ICA), which worsens ischemic stroke in the brain. A few metabolites are presumably involved in hypoxic vasoconstriction, however, less is known about how such molecules provoke this vasoconstriction. We have investigated the influence of 15-hydroxyeicosatetrienoic acid (15-HETE) produced by 15-lipoxygenase (15-LOX) on vasoconstriction during hypoxia. As showed in our results, 15-LOX level increases in ICA endothelia and smooth muscles. 15-HETE enhances the tension of ICA ring in a dose-dependent manner, as well as attenuates the activities and expression of voltage-gated potassium channels (Kv 1.5 and Kv 2.1). Therefore, the down-regulation of Kv channels by 15-HETE during hypoxia may weaken the repolarization of action potentials and causes a dominant influx of calcium ions to enhance smooth muscle tension and ICA constriction. PMID:20483431

Zhu, Yanmei; Chen, Li; Liu, Wenjuan; Wang, Weizhi; Zhu, Daling; Zhu, Yulan

2010-08-15

80

Quantitative analysis of exercise-induced enhancement of early- and late-systolic retrograde coronary blood flow  

PubMed Central

Coronary blood flow (CBF) is reduced and transiently reversed during systole via cardiac contraction. Cardiac contractility, coronary tone, and arterial pressure each influence systolic CBF (CBFSYS), particularly by modulating the retrograde component of CBFSYS. The effect of concurrent changes in these factors on CBFSYS during dynamic exercise has not been examined. Using chronically instrumented swine, we hypothesized that dynamic exercise enhances retrograde CBFSYS. Phasic CBF was examined at rest and during treadmill exercise [2–5 miles/h (mph)]. Absolute values of mean CBF over the cardiac cycle (CBFCYCLE) as well as mean CBF in diastole (CBFDIAS) and mean CBFSYS were increased by exercise, while relative CBFDIAS and CBFSYS expressed as percentage of mean CBFCYCLE were principally unchanged. Early retrograde CBFSYS was present at rest and increased in magnitude (?33 ± 4 ml/min) and as a percent of CBFCYCLE (?0.6 ± 0.1%) at 5 mph. This reversal was transient, comprising 3.7 ± 0.3% of cardiac cycle duration at 5 mph. Our results also reveal that moderately intense exercise (>3 mph) induced a second CBF reversal in late systole before aortic valve closure. At 5 mph, late retrograde CBFSYS amounted to ?53 ± 11 ml/min (?3.1 ± 0.7% of CBFCYCLE) while occupying 11.1 ± 0.3% of cardiac cycle duration. Wave-intensity analysis revealed that the second flow reversal coincided with an enhanced aortic forward-going decompression wave (vs. rest). Therefore, our data demonstrate a predictable increase in early-systolic CBF reversal during exercise and additionally that exercise induces a late-systolic CBF reversal related to the hemodynamic effects of left ventricular relaxation that is not predictable using current models of phasic CBF. PMID:20007853

van Houwelingen, Marc J.; Merkus, Daphne; Duncker, Dirk J.; Laughlin, M. Harold

2010-01-01

81

Dual-mode microwave system to enhance early detection of cancer  

NASA Technical Reports Server (NTRS)

A dual-mode microwave system has been developed that will permit early detection of cancer. The system combines the use of the passive microwave radiometer with an active transmitter. The active transmitter will provide localized heating to enhance early detection by taking advantage of the differential heating (i.e., tumor temperature with respect to surrounding tissue) associated with the thermal characteristics of tumors.

Carr, K. L.; El-Mahdi, A. M.; Shaeffer, J.

1981-01-01

82

Wind and Rotation Enhanced Escape From the Early Terrestrial Atmospheres  

NASA Astrophysics Data System (ADS)

The earliest atmospheres of the terrestrial planets are thought to have been hotter, have stronger winds and rotate faster than atmospheres of today. Since these primitive atmospheres were weakly bound, they evolved rapidly because atmospheric escape was very strong, often referred to as "blowoff." Such escape has been treated as hydrodynamic, transonic flow, similar to solar wind flow dynamics. However, in many cases the outward flow is hydrodynamic at low altitudes only to become collisionless at higher altitudes, well before sonic speeds are ever attained. Recent models dealing with such transition from fluid to kinetic flow have applied the Jeans escape flux at the exobase. This approach has lead to escape rates that are too low due to the fact that thermospheric winds and planetary rotation increase escape fluxes considerably over the corresponding Jeans fluxes (1). In particular, for a given density and temperature at the exobase, the escape flux increases as the wind speed and/or the rotation rate increase. Also, for a given wind speed and rotation rate, the escape flux enhancement over the Jeans flux increases as the mass of an escaping constituent increases, an important factor in isotope fractionation, especially the enrichment of deuterium on Mars. Accounting for a range of possible temperatures, thermospheric wind speeds and planetary rotation rates in the primitive atmospheres of the terrestrial planets, estimates are made of light constituent escape flux increases over the corresponding Jeans fluxes. (1) Hartle, R. E. and H. G. Mayr, J. Geophys. Res., 81, 1207, 1976.

Hartle, R. E.

2001-05-01

83

Hydrophilic Polymers Enhance Early Functional Outcomes after Nerve Autografting  

PubMed Central

Background Approximately 12% of operations for traumatic neuropathy are for patients with segmental nerve loss and less than 50% of these injuries obtain meaningful functional recovery. Polyethylene glycol (PEG) therapy has been shown to improve functional outcomes after nerve severance and we hypothesized this therapy could also benefit nerve autografting. Methods A segmental rat sciatic nerve injury model was used, whereby a 0.5 cm defect was repaired with an autograft using microsurgery. Experimental animals were treated with solutions containing methylene blue (MB) and PEG; control animals did not receive PEG. Compound Actions Potentials (CAPs) were recorded before nerve transection, after solution therapy, and at 72 hours postoperatively. The animals underwent behavioral testing at 24 and 72 hours postoperatively. After sacrifice, nerves were fixed, sectioned, and immunostained to allow for quantitative morphometric analysis. Results The introduction of hydrophilic polymers greatly improved morphological and functional recovery of rat sciatic axons at 1–3 days following nerve autografting. PEG therapy restored CAPs in all animals and CAPs were still present 72 hours postoperatively. No CAPS were detectable in control animals. Footfall asymmetry scores and sciatic functional index scores were significantly improved for PEG therapy group at all time points (p <0.05 and p<0.001; p <0.001 and p <0.01). Sensory and motor axon counts were increased distally in nerves treated with PEG compared to control (p = 0.0189 and p = 0.0032). Conclusions PEG therapy improves early physiologic function, behavioral outcomes, and distal axonal density after nerve autografting. PMID:22521220

Sexton, Kevin W.; Pollins, Alonda C.; Cardwell, Nancy L.; Del Corral, Gabriel A.; Bittner, George D.; Shack, R. Bruce; Nanney, Lillian B.; Thayer, Wesley P.

2014-01-01

84

Peptide-coated liposomal fasudil enhances site specific vasodilation in pulmonary arterial hypertension.  

PubMed

This study sought to develop a liposomal delivery system of fasudil--an investigational drug for the treatment of pulmonary arterial hypertension (PAH)--that will preferentially accumulate in the PAH lungs. Liposomal fasudil was prepared by film-hydration method, and the drug was encapsulated by active loading. The liposome surface was coated with a targeting moiety, CARSKNKDC, a cyclic peptide; the liposomes were characterized for size, polydispersity index, zeta potential, and storage and nebulization stability. The in vitro drug release profiles and uptake by TGF-? activated pulmonary arterial smooth muscle cells (PASMC) and alveolar macrophages were evaluated. The pharmacokinetics were monitored in male Sprague-Dawley rats, and the pulmonary hemodynamics were studied in acute and chronic PAH rats. The size, polydispersity index (PDI), and zeta potential of the liposomes were 206-216 nm, 0.058-0.084, and -20-42.7 mV, respectively. The formulations showed minimal changes in structural integrity when nebulized with a commercial microsprayer. The optimized formulation was stable for >4 weeks when stored at 4 °C. Fasudil was released in a continuous fashion over 120 h with a cumulative release of 76%. Peptide-linked liposomes were taken up at a higher degree by TGF-? activated PASMCs; but alveolar macrophages could not engulf peptide-coated liposomes. The formulations did not injure the lungs; the half-life of liposomal fasudil was 34-fold higher than that of plain fasudil after intravenous administration. Peptide-linked liposomal fasudil, as opposed to plain liposomes, reduced the mean pulmonary arterial pressure by 35-40%, without influencing the mean systemic arterial pressure. This study establishes that CAR-conjugated inhalable liposomal fasudil offers favorable pharmacokinetics and produces pulmonary vasculature specific dilatation. PMID:25333706

Nahar, Kamrun; Absar, Shahriar; Gupta, Nilesh; Kotamraju, Venkata Ramana; McMurtry, Ivan F; Oka, Masahiko; Komatsu, Masanobu; Nozik-Grayck, Eva; Ahsan, Fakhrul

2014-12-01

85

Coronary artery remodeling in non-contrast CT images  

NASA Astrophysics Data System (ADS)

A significant cause of coronary artery disease is the coronary atherosclerosis which leads to stenosis of coronary arteries. It has been shown in recent studies, using intravascular ultrasound and contrast-enhanced CT, that early atherosclerosis causes positive coronary artery remodeling, defined as increases in the cross-sectional area. It is hypothesized that detection of artery remodeling using non-contrast CT can be an important factor in sub-clinical assessment of cardiac risk for asymptomatic subjects. However, measuring remodeling in coronary arteries in non-contrast CT images is a challenging task because coronary arteries are small and the intensity of coronary arteries is similar to that of surrounding tissues. Automatic segmentation algorithms that have been successful in segmenting coronary arteries in contrast-enhanced images do not perform well. To overcome these difficulties, we developed an interactive application to enable effective measurement of coronary artery remodeling in non-contrast CT images. This application is an extension to the 3D Slicer image analysis platform. It allows users to visualize and trace the centerline of arteries in cross sectional views. The artery centerlines are displayed in a three dimensional view overlaid on the original image volume and color-coded according to the artery labels. Using this 3D artery model, the user can sample the cross-sectional area of the arteries at selected points for remodeling assessment. Initial validation has demonstrated the effectiveness of this method. A pilot study also showed positive correlation of large coronary artery remodeling with highest lifetime risks. Further evaluation is underway using larger study size and more measurement points.

Xu, Haiyong; Zheng, Mingna; Yang, Yanhua; Carr, J. Jeffery; Ge, Yaorong

2012-03-01

86

Association of CD36 gene polymorphisms with echo- and electrocardiographic parameters in patients with early onset coronary artery disease  

PubMed Central

Introduction CD36 plays an important role in long-chain fatty acid homeostasis in skeletal muscle and the myocardium. CD36 deficiency may lead to reduced myocardial uptake of long-chain fatty acid. Therefore, different mutations of the CD36 gene may contribute to the clinical heterogeneity of cardiac hypertrophy. Material and methods The objective of the study was to investigate whether there is an association between the sequence changes in CD36 and echocardiographic and electrocardiographic parameters in Caucasian patients with early onset coronary artery disease. The study group comprised 100 patients. Electrocardiography and echocardiography were performed in all patients. Amplicons of exons 4 to 6 including fragments of introns were studied using the denaturing high-performance liquid chromatography technique. Results IVS3-6TC (rs3173798) heterozygotes had impaired left ventricle diastolic function. 573GA heterozygotes (rs5956) had higher frequency of pseudonormal left ventricular diastolic function and it was confirmed by the increase in wave A’ in the tissue Doppler. 591AT genotype was associated with borderline higher posterior wall end-diastolic thickness and lower E/A ratio. These results are consistent with electrocardiography parameters which could reflect left ventricular hypertrophy (higher RV5(6) and RV5(6) + SV1(2) parameters, depressed ST segments and tendency to longer Qtc II interval) in 591AT heterozygotes. Conclusions Detected variant alleles of CD36 may be associated with features of left ventricular hypertrophy and impaired diastolic function. PMID:24049523

Kurzawski, Grzegorz; Safranow, Krzysztof; Rac, Michal; Sagasz-Tysiewicz, Dagmara; Krzystolik, Andrzej; Poncyljusz, Wojciech; Olszewska, Maria; Dawid, Gra?yna; Chlubek, Dariusz

2012-01-01

87

Dynamic Contrast-Enhanced MRI Assessment of Hyperemic Fractional Microvascular Blood Plasma Volume in Peripheral Arterial Disease: Initial Findings  

PubMed Central

Objectives The aim of the current study was to describe a method that assesses the hyperemic microvascular blood plasma volume of the calf musculature. The reversibly albumin binding contrast agent gadofosveset was used in dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) to assess the microvascular status in patients with peripheral arterial disease (PAD) and healthy controls. In addition, the reproducibility of this method in healthy controls was determined. Materials and Methods Ten PAD patients with intermittent claudication and 10 healthy control subjects were included. Patients underwent contrast-enhanced MR angiography of the peripheral arteries, followed by one DCE MRI examination of the musculature of the calf. Healthy control subjects were examined twice on different days to determine normative values and the interreader and interscan reproducibility of the technique. The MRI protocol comprised dynamic imaging of contrast agent wash-in under reactive hyperemia conditions of the calf musculature. Using pharmacokinetic modeling the hyperemic fractional microvascular blood plasma volume (Vp, unit: %) of the anterior tibial, gastrocnemius and soleus muscles was calculated. Results Vp was significantly lower for all muscle groups in PAD patients (4.3±1.6%, 5.0±3.3% and 6.1±3.6% for anterior tibial, gastrocnemius and soleus muscles, respectively) compared to healthy control subjects (9.1±2.0%, 8.9±1.9% and 9.3±2.1%). Differences in Vp between muscle groups were not significant. The coefficient of variation of Vp varied from 10–14% and 11–16% at interscan and interreader level, respectively. Conclusions Using DCE MRI after contrast-enhanced MR angiography with gadofosveset enables reproducible assessment of hyperemic fractional microvascular blood plasma volume of the calf musculature. Vp was lower in PAD patients than in healthy controls, which reflects a promising functional (hemodynamic) biomarker for the microvascular impairment of macrovascular lesions. PMID:22662212

Versluis, Bas; Dremmen, Marjolein H. G.; Nelemans, Patty J.; Wildberger, Joachim E.; Schurink, Geert-Willem; Leiner, Tim; Backes, Walter H.

2012-01-01

88

Elastin-derived peptides stimulate trophoblast migration and invasion: a positive feedback loop to enhance spiral artery remodelling.  

PubMed

Elastin breakdown in the walls of uterine spiral arteries during early pregnancy facilitates their transformation into dilated, high-flow, low-resistance channels. Elastin-derived peptides (EDP) can influence cell migration, invasion and protease activity, and so we hypothesized that EDP released during elastolysis promote extravillous trophoblast (EVT) invasion and further elastin breakdown. Treatment of the trophoblast cell line SGHPL4 with the elastin-derived matrikine VGVAPG (1 ?g/ml) significantly increased total elastase activity, promoted migration in a wound healing assay and increased invasion through Matrigel-coated transwells compared with vehicle control (0.1% DMSO) or the scrambled sequence VVGPGA. Furthermore, treatment of first-trimester placental villous explants with this EDP significantly increased both the area of trophoblast outgrowth and distance of migration away from the villous tips. Primary first-trimester cytotrophoblast exposed to VGVAPG (1 ?g/ml) for 30 min showed increased phosphorylation of endothelial nitric oxide synthase and activation of the mitogen activated protein kinase pathway, events also associated with tumour cell migration and invasion. These in vitro observations suggest liberation of bioactive EDP during induction of elastolysis in the uterine spiral arteries may orchestrate a positive feedback loop that promotes EVT invasion and further elastin breakdown, contributing to the process of vascular remodelling. PMID:25245255

Desforges, Michelle; Harris, Lynda K; Aplin, John D

2015-01-01

89

Enhanced Visual Speech Perception in Individuals with Early-Onset Hearing Impairment  

ERIC Educational Resources Information Center

Purpose: L. E. Bernstein, M. E. Demorest, and P. E. Tucker (2000) demonstrated enhanced speechreading accuracy in participants with early-onset hearing loss compared with hearing participants. Here, the authors test the generalization of Bernstein et al.'s (2000) result by testing 2 new large samples of participants. The authors also investigated…

Auer, Edward T., Jr.; Bernstein, Lynne E.

2007-01-01

90

Enhancing Early Literacy Skills for Preschool Children: Bringing a Professional Development Model to Scale  

ERIC Educational Resources Information Center

A quasi-experimental, statewide intervention targeting preschool teachers' enhancement of children's language and early literacy was evaluated. Across 2 years and 20 Head Start sites, 750 teachers participated (500 target, 250 control), with 370 classrooms randomly selected to conduct pre- and posttest assessments (10 randomly selected children…

Landry, Susan H.; Swank, Paul R.; Smith, Karen E.; Assel, Michael A.; Gunnewig, Susan B.

2006-01-01

91

Feedback Seeking in Early Adolescence: Self-Enhancement or Self-Verification?  

ERIC Educational Resources Information Center

The authors examined whether early adolescents ("N" = 90) solicit self-enhancing feedback (i.e., positive feedback) or self-verifying feedback (i.e., feedback congruent with self-views, even when these views are negative). Sixth, seventh, and eighth graders first completed a self-perception measure and then selected whether to receive…

Rosen, Lisa H.; Principe, Connor P.; Langlois, Judith H.

2013-01-01

92

Early life antibiotic-driven changes in microbiota enhance susceptibility to allergic asthma  

E-print Network

Early life antibiotic-driven changes in microbiota enhance susceptibility to allergic asthma City, Quebec, Canada Allergic asthma rates have increased steadily in developed countries, arguing for an environmental aetiology. To assess the influence of gut microbiota on experimental murine allergic asthma, we

Strynadka, Natalie

93

Enhancement of Autophagy by Simvastatin through Inhibition of Rac1-mTOR Signaling Pathway in Coronary Arterial Myocytes  

PubMed Central

Background/Aims In addition to their action of lowering blood cholesterol levels, statins modulate biological characteristics and functions of arterial myocytes such as viability, proliferation, apoptosis, survival and contraction. The present study tested whether simvastatin, as a prototype statin, enhances autophagy in coronary arterial myocytes (CAMs) to thereby exert their beneficial effects in atherosclerosis. Methods and Results Using flow cytometry, we demonstrated that simvastatin significantly increased the autophagsome formation in CAMs. Western blot analysis confirmed that simvastatin significantly increased protein expression of typical autophagy markers LC3B and Beclin1 in these CAMs. Confocal microscopy further demonstrated that simvastatin increased fusion of autophagosomes with lysosomes, which was blocked by autophagy inhibitor 3-methyladenine or silencing of Atg7 genes. Simvastatin reduced mammalian target of rapamycin (mTOR) activity, which was reversed by Rac1-GTPase overexpression and the mTOR agonist phosphatidic acid. Moreover, both Rac1-GTPase overexpression and activation of mTOR by phosphatidic acid drastically blocked simvastatin-induced autophagosome formation in CAMs. Interestingly, simvastatin increased protein expression of a contractile phenotype marker calponin in CAMs, which was blocked by autophagy inhibitor 3-methyladenine. Simvastatin markedly reduced proliferation of CAMs under both control and proatherogenic stimulation. However, this inhibitory effect of simvastatin on CAM proliferation was blocked by by autophagy inhibitor 3-methyladenine or silencing of Atg7 genes. Lastly, animal experiments demonstrated that simvastatin increased protein expression of LC3B and calponin in mouse coronary arteries. Conclusion Our results indicate that simvastatin inhibits the Rac1-mTOR pathway and thereby increases autophagy in CAMs which may stabilize CAMs in the contractile phenotype to prevent proliferation and growth of these cells. PMID:23817226

Wei, Yu-Miao; Li, Xiang; Xu, Ming; Abais, Justine M.; Chen, Yang; Riebling, Christopher R.; Boini, Krishna M.; Li, Pin-Lan; Zhang, Yang

2013-01-01

94

Angiotensin-(1-9), the product of angiotensin I conversion in platelets, enhances arterial thrombosis in rats.  

PubMed

Angiotensin (Ang) (1-9) is the renin-angiotensin-system peptide found in the plasma of healthy volunteers and after angiotensin-converting-enzyme inhibitors therapy. In vitro experiments proved that Ang-(1-9) may be produced from Ang I. In our study, we tried to expand the poor data about the in vivo properties of Ang-(1-9). We revealed that Ang-(1-9) enhanced electrically stimulated arterial thrombosis in the carotid artery of Wistar rats. Losartan, a selective blocker of AT1 receptor for Ang II, abolished the prothrombotic activity of Ang-(1-9). This peptide increased plasma level of fibrinogen, augments fibrin generation, and similarly to Ang II, potentiated collagen induced platelet aggregation. Using HPLC, we found that after incubation of Ang-(1-9) with platelet homogenates or after intravenous administration this peptide is converted to Ang II. We concluded that Ang-(1-9) exerts an Ang II-like prothrombotic effect due to the conversion to Ang II in the circulatory system of rats and that platelets are involved in this process. PMID:20610862

Kramkowski, K; Mogielnicki, A; Leszczynska, A; Buczko, W

2010-06-01

95

Albumin therapy enhances collateral perfusion after laser-induced middle cerebral artery branch occlusion: a laser speckle contrast flow study  

PubMed Central

Laser speckle contrast (LSC) was used to compare the extent of cortical ischemia in two inbred mouse strains that differed in their degree of collateral circulation, after laser occlusion of the distal middle cerebral artery, and after treatment with 25% albumin (ALB) or saline (control). Sequential LSC images acquired over ?90?minutes were coaligned, converted to relative flow, and normalized to baseline. After 3-day survival, infarction was quantified by triphenyl tetrazolium chloride or magnetic resonance imaging. In the sparsely collateralized BALB/c strain, mean flow fell to 13% to 14% and 33% to 34% of baseline in central (core) and peripheral (penumbral) regions of interest, and ALB treatment at 30?minutes enhanced perfusion in both regions by ?2-fold relative to saline, restoring flow to the benign-oligemic range centrally, and to the hyperemic range peripherally. The ALB-induced increment in parenchymal perfusion was disproportionate to the subtle flow increase in the occluded artery itself, suggesting that ALB improved collateral circulation. Cortical infarction in BALB/c mice was reduced 45% by ALB treatment. In contrast to BALB/c mice, the better-collateralized CD-1 strain developed milder ischemia, had smaller infarcts, and showed no differential benefit of ALB. We conclude that where native collateralization is insufficient (BALB/c strain), ALB treatment exerts a significant therapeutic effect after ischemia by augmenting collateral perfusion. PMID:22781334

DeFazio, Richard A; Zhao, Weizhao; Deng, Xiaolu; Obenaus, Andre; Ginsberg, Myron D

2012-01-01

96

Comparison of model-based arterial input functions for dynamic contrast-enhanced MRI in tumor bearing rats.  

PubMed

When using tracer kinetic modeling to analyze dynamic contrast-enhanced MRI (DCE-MRI) it is necessary to identify an appropriate arterial input function (AIF). The measured AIF is often poorly sampled in both clinical and preclinical MR systems due to the initial rapid increase in contrast agent concentration and the subsequent large-scale signal change that occurs in the arteries. However, little work has been carried out to quantify the sensitivity of tracer kinetic modeling parameters to the form of AIF. Using a preclinical experimental data set, we sought to measure the effect of varying model forms of AIF on the extended Kety compartmental model parameters (K(trans), v(e), and v(p)) through comparison with the results of experimentally acquired high temporal resolution AIFs. The AIF models examined have the potential to be parameterized on lower temporal resolution data to predict the form of the true, higher temporal resolution AIF. The models were also evaluated through application to the population average AIF. It was concluded that, in the instance of low temporal resolution or noisy data, it may be preferable to use a bi-exponential model applied to the raw data AIF, or when individual measurements are not available a bi-exponential model of the average AIF. PMID:19253360

McGrath, Deirdre M; Bradley, Daniel P; Tessier, Jean L; Lacey, Tony; Taylor, Chris J; Parker, Geoffrey J M

2009-05-01

97

Modulation of the effects of norepinephrine uptake inhibitors on the norepinephrine-induced contractile response of the porcine uterine artery during early pregnancy.  

PubMed Central

The effects of norepinephrine (NE) uptake inhibitors on the porcine uterine artery's contractile response to NE and their potential alteration during early pregnancy (Day 13 postcoitus; day of coitus = Day 0) in comparison with the end of the luteal phase (Days 11-14; first day of behavioral estrus = Day 0) was investigated. This pregnancy time point is characterized by a transient increase in resting uterine blood flow dependent on the presence of blastocysts, an increased endometrial vascular permeability, and the beginning of the endometrial attachment of the blastocysts. A cumulative concentration-response curve (CCRC) to NE was produced in isometrically-mounted rings. Cocaine (5 microM) was used to inhibit neuronal NE uptake and hydrocortisone (30 microM) was used to inhibit extraneuronal NE uptake. Either drug alone induced a leftward shift of the CCRC to NE without affecting the maximal response. This shift had the same amplitude at the end of the luteal phase and in early pregnancy. However, the leftward shift induced by cocaine was larger than that induced by hydrocortisone only in early pregnancy, and the leftward shift induced by exposure to both hydrocortisone and cocaine was larger in early pregnancy than at the end of the luteal phase. These results suggest that a significant sensitization of the contractile response of the porcine uterine artery to NE is induced by neuronal and extraneuronal uptake inhibitors and that this effect is altered in early pregnancy, possibly reflecting the existence of a mechanism protecting the uterine artery against excessive sympathetic stimulation. PMID:9243002

Laporte, R; DeRoth, L

1997-01-01

98

Can contrast-enhanced ultrasound with second-generation contrast agents replace computed tomography angiography for distinguishing between occlusion and pseudo-occlusion of the internal carotid artery?  

PubMed Central

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of contrast-enhanced ultrasound with a second-generation contrast agent in distinguishing between occlusion and pseudo-occlusion of the cervical internal carotid artery, comparing it with that of conventional Doppler ultrasound and the gold standard, computed tomography angiography. METHOD: Between June 2006 and June 2012, we screened 72 symptomatic vascular surgery outpatients at a public hospital. Among those patients, 78 cervical internal carotid arteries were previously classified as occluded by Doppler ultrasound (without contrast). The patients were examined again with Doppler ultrasound, as well as with contrast-enhanced ultrasound and computed tomography angiography. The diagnosis was based on the presence or absence of flow. RESULTS: Among the 78 cervical internal carotid arteries identified as occluded by Doppler ultrasound, occlusion was confirmed by computed tomography angiography in only 57 (73.1%), compared with 59 (77.5%) for which occlusion was confirmed by contrast-enhanced ultrasound (p>0.5 vs. computed tomography angiography). Comparing contrast-enhanced ultrasound with Doppler ultrasound, we found that the proportion of cervical internal carotid arteries classified as occluded was 24.4% higher when the latter was used (p<0.001). CONCLUSIONS: We conclude that, in making the differential diagnosis between occlusion and pseudo-occlusion of the cervical internal carotid artery, contrast-enhanced ultrasound with a second-generation contrast agent is significantly more effective than conventional Doppler ultrasound and is equally as effective as the gold standard (computed tomography angiography). Our findings suggest that contrast-enhanced ultrasound could replace computed tomography angiography in this regard.

Ventura, Carlos Augusto Pinto; da Silva, Erasmo Simão; Cerri, Giovanni Guido; Leão, Pedro Puech; Tachibana, Adriano; Chammas, Maria Cristina

2015-01-01

99

Polycomb Binding Precedes Early-Life Stress Responsive DNA Methylation at the Avp Enhancer  

PubMed Central

Early-life stress (ELS) in mice causes sustained hypomethylation at the downstream Avp enhancer, subsequent overexpression of hypothalamic Avp and increased stress responsivity. The sequence of events leading to Avp enhancer methylation is presently unknown. Here, we used an embryonic stem cell-derived model of hypothalamic-like differentiation together with in vivo experiments to show that binding of polycomb complexes (PcG) preceded the emergence of ELS-responsive DNA methylation and correlated with gene silencing. At the same time, PcG occupancy associated with the presence of Tet proteins preventing DNA methylation. Early hypothalamic-like differentiation triggered PcG eviction, DNA-methyltransferase recruitment and enhancer methylation. Concurrently, binding of the Methyl-CpG-binding and repressor protein MeCP2 increased at the enhancer although Avp expression during later stages of differentiation and the perinatal period continued to increase. Overall, we provide evidence of a new role of PcG proteins in priming ELS-responsive DNA methylation at the Avp enhancer prior to epigenetic programming consistent with the idea that PcG proteins are part of a flexible silencing system during neuronal development. PMID:24599304

Murgatroyd, Chris; Spengler, Dietmar

2014-01-01

100

Polycomb binding precedes early-life stress responsive DNA methylation at the Avp enhancer.  

PubMed

Early-life stress (ELS) in mice causes sustained hypomethylation at the downstream Avp enhancer, subsequent overexpression of hypothalamic Avp and increased stress responsivity. The sequence of events leading to Avp enhancer methylation is presently unknown. Here, we used an embryonic stem cell-derived model of hypothalamic-like differentiation together with in vivo experiments to show that binding of polycomb complexes (PcG) preceded the emergence of ELS-responsive DNA methylation and correlated with gene silencing. At the same time, PcG occupancy associated with the presence of Tet proteins preventing DNA methylation. Early hypothalamic-like differentiation triggered PcG eviction, DNA-methyltransferase recruitment and enhancer methylation. Concurrently, binding of the Methyl-CpG-binding and repressor protein MeCP2 increased at the enhancer although Avp expression during later stages of differentiation and the perinatal period continued to increase. Overall, we provide evidence of a new role of PcG proteins in priming ELS-responsive DNA methylation at the Avp enhancer prior to epigenetic programming consistent with the idea that PcG proteins are part of a flexible silencing system during neuronal development. PMID:24599304

Murgatroyd, Chris; Spengler, Dietmar

2014-01-01

101

Milk production, plasma metabolite profiles and mammary arterial-venous differences of milk precursors in early lactation cows milked at different frequencies by an automatic milking system.  

PubMed

The objective of this study was to clarify the effect of different milking frequencies under an automatic milking system (AMS) on milk yield, plasma metabolite profiles and mammary arterial-venous (A-V) differences of milk precursors by mammary tissues in early lactation cows. Twelve Holstein cows were divided into two and four times milking frequency treatments by AMS after calving to 50 days postpartum. Cows were given a partial mixed ration ad libitum and a concentrate diet at every milking. Dry matter intake increased similarly in both treatments with advancing postpartum days. Milk yield was greater (P?Arterial concentrations of glucose and glutamate were lower (P?arterial concentration of nonesterified fatty acids did not differ between treatments. Although mammary A-V differences of plasma concentration for most milk precursors did not differ between treatments, estimated plasma flow was higher (P?early lactating cows from day 20 postpartum onward. PMID:25474097

Astuti, Andriyani; Obitsu, Taketo; Sugino, Toshihisa; Taniguchi, Kohzo; Okita, Miki; Kurokawa, Yuzo

2014-12-01

102

Automated coronary artery tree extraction in coronary CT angiography using a multiscale enhancement and dynamic balloon tracking (MSCAR-DBT) method  

PubMed Central

Rational and Objectives To evaluate our prototype method for segmentation and tracking of the coronary arterial tree, which is the foundation for a computer-aided detection (CADe) system to be developed to assist radiologists in detecting non-calcified plaques in coronary CT angiography (cCTA) scans. Materials and Methods The heart region was first extracted by a morphological operation and an adaptive thresholding method based on expectation-maximization (EM) estimation. The vascular structures within the heart region were enhanced and segmented using a multiscale coronary response (MSCAR) method that combined 3D multiscale filtering, analysis of the eigen values of Hessian matrices and EM estimation segmentation. After the segmentation of vascular structures, the coronary arteries were tracked by a 3D dynamic balloon tracking (DBT) method. The DBT method started at two manually identified seed points located at the origins of the left and right coronary arteries (LCA and RCA) for extraction of the arterial trees. The coronary arterial trees of a data set containing 20 ECG-gated contrast-enhanced cCTA scans were extracted by our MSCAR-DBT method and a clinical GE Advantage workstation. Two experienced thoracic radiologists visually examined the coronary arteries on the original cCTA scans and the rendered volume of segmented vessels to count the untracked false-negative (FN) segments and false positives (FPs) for both methods. Results For the visible coronary arterial segments in the 20 cases, the radiologists identified that 25 segments were missed by our MSCAR-DBT method, ranging from 0 to 5 FN segments in individual cases, and that 55 artery segments were missed by the GE software, ranging from 0 to 7 FN segments in individual cases. 19 and 15 FPs were identified in our and the GE coronary trees, ranging from 0 to 4 FPs for both methods in individual cases, respectively. Conclusion The preliminary study demonstrates the feasibility of our MSCAR-DBT method for segmentation and tracking coronary artery trees. The results indicated that both our method and GE software can extract coronary artery trees reasonably well and the performance of our method is superior to that of GE software in this small data set. Further studies are underway to develop methods for improvement of the segmentation and tracking accuracy. PMID:21601422

Zhou, Chuan; Chan, Heang-Ping; Chughtai, Aamer; Patel, Smita; Hadjiiski, Lubomir M.; Wei, Jun; Kazerooni, Ella A.

2011-01-01

103

Enhanced transcription and translation in clay hydrogel and implications for early life evolution  

PubMed Central

In most contemporary life forms, the confinement of cell membranes provides localized concentration and protection for biomolecules, leading to efficient biochemical reactions. Similarly, confinement may have also played an important role for prebiotic compartmentalization in early life evolution when the cell membrane had not yet formed. It remains an open question how biochemical reactions developed without the confinement of cell membranes. Here we mimic the confinement function of cells by creating a hydrogel made from geological clay minerals, which provides an efficient confinement environment for biomolecules. We also show that nucleic acids were concentrated in the clay hydrogel and were protected against nuclease, and that transcription and translation reactions were consistently enhanced. Taken together, our results support the importance of localized concentration and protection of biomolecules in early life evolution, and also implicate a clay hydrogel environment for biochemical reactions during early life evolution. PMID:24196527

Yang, Dayong; Peng, Songming; Hartman, Mark R.; Gupton-Campolongo, Tiffany; Rice, Edward J.; Chang, Anna Kathryn; Gu, Zi; Lu, G. Q. (Max); Luo, Dan

2013-01-01

104

Enhanced transcription and translation in clay hydrogel and implications for early life evolution  

NASA Astrophysics Data System (ADS)

In most contemporary life forms, the confinement of cell membranes provides localized concentration and protection for biomolecules, leading to efficient biochemical reactions. Similarly, confinement may have also played an important role for prebiotic compartmentalization in early life evolution when the cell membrane had not yet formed. It remains an open question how biochemical reactions developed without the confinement of cell membranes. Here we mimic the confinement function of cells by creating a hydrogel made from geological clay minerals, which provides an efficient confinement environment for biomolecules. We also show that nucleic acids were concentrated in the clay hydrogel and were protected against nuclease, and that transcription and translation reactions were consistently enhanced. Taken together, our results support the importance of localized concentration and protection of biomolecules in early life evolution, and also implicate a clay hydrogel environment for biochemical reactions during early life evolution.

Yang, Dayong; Peng, Songming; Hartman, Mark R.; Gupton-Campolongo, Tiffany; Rice, Edward J.; Chang, Anna Kathryn; Gu, Zi; Lu, G. Q. (Max); Luo, Dan

2013-11-01

105

3D GRASE pulsed arterial spin labeling at multiple inflow times in patients with long arterial transit times: comparison with dynamic susceptibility-weighted contrast-enhanced MRI at 3 Tesla.  

PubMed

Pulsed arterial spin labeling (PASL) at multiple inflow times (multi-TIs) is advantageous for the measurement of brain perfusion in patients with long arterial transit times (ATTs) as in steno-occlusive disease, because bolus-arrival-time can be measured and blood flow measurements can be corrected accordingly. Owing to its increased signal-to-noise ratio, a combination with a three-dimensional gradient and spin echo (GRASE) readout allows acquiring a sufficient number of multi-TIs within a clinically feasible acquisition time of 5?minutes. We compared this technique with the clinical standard dynamic susceptibility-weighted contrast-enhanced imaging-magnetic resonance imaging in patients with unilateral stenosis >70% of the internal carotid or middle cerebral artery (MCA) at 3 Tesla. We performed qualitative (assessment by three expert raters) and quantitative (region of interest (ROI)/volume of interest (VOI) based) comparisons. In 43 patients, multi-TI PASL-GRASE showed perfusion alterations with moderate accuracy in the qualitative analysis. Quantitatively, moderate correlation coefficients were found for the MCA territory (ROI based: r=0.52, VOI based: r=0.48). In the anterior cerebral artery (ACA) territory, a readout related right-sided susceptibility artifact impaired correlation (ROI based: r=0.29, VOI based: r=0.34). Arterial transit delay artifacts were found only in 12% of patients. In conclusion, multi-TI PASL-GRASE can correct for arterial transit delay in patients with long ATTs. These results are promising for the transfer of ASL to the clinical practice.Journal of Cerebral Blood Flow & Metabolism advance online publication, 19 November 2014; doi:10.1038/jcbfm.2014.200. PMID:25407272

Martin, Steve Z; Madai, Vince I; von Samson-Himmelstjerna, Federico C; Mutke, Matthias A; Bauer, Miriam; Herzig, Cornelius X; Hetzer, Stefan; Günther, Matthias; Sobesky, Jan

2014-11-19

106

Cerebrospinal Fluid Enhancement on Fluid Attenuated Inversion Recovery Images After Carotid Artery Stenting with Neuroprotective Balloon Occlusions: Hemodynamic Instability and Blood-Brain Barrier Disruption  

SciTech Connect

Purpose: A rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood-brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images. Methods: Nineteen patients-5 acute-phase and 14 scheduled-underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors were examined. Results: CSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients. Conclusions: Ischemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.

Ogami, Ryo, E-mail: ogami.r@mazda.co.jp; Nakahara, Toshinori [Mazda Hospital, Department of Neurosurgery (Japan); Hamasaki, Osamu [Shimane Prefectural Central Hospital, Department of Neurosurgery (Japan); Araki, Hayato [Mazda Hospital, Department of Neurosurgery (Japan); Kurisu, Kaoru [Hiroshima University Graduate School of Biomedical Sciences, Department of Neurosurgery (Japan)

2011-10-15

107

An arterial-specific enhancer of the human endothelin converting enzyme1 (ECE1) gene is synergistically activated by Sox17, FoxC2, and Etv2.  

PubMed

Endothelin-converting enzyme-1 (Ece-1), a crucial component of the Endothelin signaling pathway, is required for embryonic development and is an important regulator of vascular tone, yet the transcriptional regulation of the ECE1 gene has remained largely unknown. Here, we define the activity and regulation of an enhancer from the human ECE1 locus in vivo. The enhancer identified here becomes active in endothelial progenitor cells shortly after their initial specification and is dependent on a conserved FOX:ETS motif, a composite binding site for Forkhead transcription factors and the Ets transcription factor Etv2, for activity in vivo. The ECE1 FOX:ETS motif is bound and cooperatively activated by FoxC2 and Etv2, but unlike other described FOX:ETS-dependent enhancers, ECE1 enhancer activity becomes restricted to arterial endothelium and endocardium by embryonic day 9.5 in transgenic mouse embryos. The ECE1 endothelial enhancer also contains an evolutionarily-conserved, consensus SOX binding site, which is required for activity in transgenic mouse embryos. Importantly, the ECE1 SOX site is bound and activated by Sox17, a transcription factor involved in endothelial cell differentiation and an important regulator of arterial identity. Moreover, the ECE1 enhancer is cooperatively activated by the combinatorial action of FoxC2, Etv2, and Sox17. Although Sox17 is required for arterial identity, few direct transcriptional targets have been identified in endothelial cells. Thus, this work has important implications for our understanding of endothelial specification and arterial subspecification. PMID:25179465

Robinson, Ashley S; Materna, Stefan C; Barnes, Ralston M; De Val, Sarah; Xu, Shan-Mei; Black, Brian L

2014-11-15

108

Motor balance and coordination training enhances functional outcome in rat with transient middle cerebral artery occlusion.  

PubMed

The goal of this study was to determine if relatively complex motor training on Rota-rod involving balance and coordination plays an essential role in improving motor function in ischemic rats, as compared with simple locomotor exercise on treadmill. Adult male Sprague-Dawley rats with (n=40) or without (n=40) ischemia were trained under each of three conditions: (1) motor balance and coordination training on Rota-rod; (2) simple exercise on treadmill; and (3) non-trained controls. Motor function was evaluated by a series of tests (foot fault placing, parallel bar crossing, rope and ladder climbing) before and at 14 or 28 days after training procedures in both ischemic and normal animals. Infarct volume in ischemic animals was determined with Nissl staining. Compared with both treadmill exercised and non-trained animals, Rota-rod-trained animals with or without ischemia significantly (P<0.01) improved motor performance of all tasks except for foot fault placing after 14 days of training, with normal rats having better performance. Animals trained for up to 28 days on the treadmill did not show significantly improved function. With regard to foot fault placing task, performance on foot placing was improved in ischemic rats across the three measurements at 0, 14 and 28 days regardless of training condition, while the normal group reached their best performance at the beginning of measurement. No significant differences in infarct volume were found in rats trained either with Rota-rod (47+/-4%; mean+/-S.E.), treadmill (45+/-5%) or non-exercised control (45+/-3%). In addition, no obvious difference could be detected in the location of the damage which included the dorso-lateral portion of the neostriatum and the frontoparietal cortex, the main regions supplied by the middle cerebral artery. The data suggest that complex motor training rather than simple exercise effectively improves functional outcome. PMID:14706778

Ding, Y; Li, J; Lai, Q; Rafols, J A; Luan, X; Clark, J; Diaz, F G

2004-01-01

109

Arterial line pressure control enhanced extracorporeal blood flow prescription in hemodialysis patients  

PubMed Central

Background In hemodialysis, extracorporeal blood flow (Qb) recommendation is 300–500 mL/min. To achieve the best Qb, we based our prescription on dynamic arterial line pressure (DALP). Methods This prospective study included 72 patients with catheter Group 1 (G1), 1877 treatments and 35 arterio-venous (AV) fistulae Group 2 (G2), 1868 treatments. The dialysis staff was trained to prescribe Qb sufficient to obtain DALP between -200 to -250 mmHg. We measured ionic clearance (IK: mL/min), access recirculation, DALP (mmHg) and Qb (mL/min). Six prescription zones were identified: from an optimal A zone (Qb > 400, DALP -200 to -250) to zones with lower Qb E (Qb < 300, DALP -200 to -250) and F (Qb < 300, DALP > -199). Results Treatments distribution in A was 695 (37%) in G1 vs. 704 (37.7%) in G2 (P = 0.7). In B 150 (8%) in G1 vs. 458 (24.5%) in G2 (P < 0.0001). Recirculation in A was 10.0% (Inter quartile rank, IQR 6.5, 14.2) in G1 vs. 9.8% (IQR 7.5, 14.1) in G2 (P = 0.62). IK in A was 214 ± 34 (G1) vs. 213 ± 35 (G2) (P = 0.65). IK Anova between G2 zones was: A vs. C and D (P < 0.000001). Staff prescription adherence was 81.3% (G1) vs. 84.1% (G2) (P = 0.02). Conclusion In conclusion, an optimal Qb can de prescribed with DALP of -200 mmHg. Staff adherence to DLAP treatment prescription could be reached up to 81.3% in catheters and 84.1% in AV fistulae. PMID:19025625

Mora-Bravo, Franklin G; Mariscal, Alfonso; Herrera–Felix, Juan P; Magaña, Salvador; De-La-Cruz, Guadalupe; Flores, Nelly; Rosales, Laura; Franco, Martha; Pérez-Grovas, Héctor

2008-01-01

110

Exercise training reverses unparallel downregulation of MaxiK channel ?- and ?1-subunit to enhance vascular function in aging mesenteric arteries.  

PubMed

This study was designed to determine the effects of aerobic exercise training on aging-associated selective changes of the function and expression of the large-conductance Ca(2+)-activated K(+) (MaxiK) channels in mesenteric arteries. Male Wistar rats aged 19-21 months were randomly assigned to sedentary (O-SED) and exercise-trained groups (O-EX). Two-month-old rats were used as Young control. Addition of iberiotoxin (10(-8) M) increased the norepinephrine-induced arterial contraction in all three groups, with the greatest enhancement being in Young and the least in O-SED. Patch clamp study revealed the characteristics of aging on MaxiK channel function in mesenteric arteries, mainly including (a) decrease of iberiotoxin-sensitive whole-cell K(+) current, (b) decrease of open probability and Ca(2+)/voltage sensitivity of single MaxiK channel, and (c) reduction of tamoxifen-induced MaxiK activation. After exercise training, all of these changes were markedly inhibited. Western blotting revealed that the protein expression of MaxiK was significantly reduced with aging and the suppression of ?1-subunit was larger than that of ?-subunit, although exercise training diminished this alteration. Taken together, aerobic exercise training reverses the aging-related unparallel downregulation of MaxiK ?- and ?1-subunit expression on mesenteric arteries, which partly underlies the beneficial effect of exercise on restoring aging-associated reduction in mesenteric artery vasodilatory properties. PMID:24347614

Shi, Lijun; Liu, Bailin; Zhang, Yanyan; Xue, Zhimin; Liu, Yujia; Chen, Yu

2014-12-01

111

Orientation enhancement in early visual processing can explain time course of brightness contrast and White's illusion.  

PubMed

Dynamics of orientation tuning in V1 indicates that computational model of V1 should not only comprise of bank of static spatially oriented filters but also include the contribution for dynamical response facilitation or suppression along orientation. Time evolution of orientation response in V1 can emerge due to time- dependent excitation and lateral inhibition in the orientation domain. Lateral inhibition in the orientation domain suggests that Ernst Mach's proposition can be applied for the enhancement of initial orientation distribution that is generated due to interaction of visual stimulus with spatially oriented filters and subcortical temporal filter. Oriented spatial filtering that appears much early (<70 ms) in the sequence of visual information processing can account for many of the brightness illusions observed at steady state. It is therefore expected that time evolution of orientation response might be reflecting in the brightness percept over time. Our numerical study suggests that only spatio-temporal filtering at early phase can explain experimentally observed temporal dynamics of brightness contrast illusion. But, enhancement of orientation response at early phase of visual processing is the key mechanism that can guide visual system to predict the brightness by "Max-rule" or "Winner Takes All" (WTA) estimation and thus producing White's illusions at any exposure. PMID:23456306

Karmakar, Subhajit; Sarkar, Sandip

2013-06-01

112

Early detection of coronary artery disease in patients studied with magnetocardiography: an automatic classification system based on signal entropy.  

PubMed

We propose an automatic system for the classification of coronary artery disease (CAD) based on entropy measures of MCG recordings. Ten patients with coronary artery narrowing ? or ? 50% were categorized by a multilayer perceptron (MLP) neural network based on Linear Discriminant Analysis (LDA). Best results were obtained with MCG at rest: 99% sensitivity, 97% specificity, 98% accuracy, 96% and 99% positive and negative predictive values for single heartbeats. At patient level, these results correspond to a correct classification of all patients. The classifier's suitability to detect CAD-induced changes on the MCG at rest was validated with surrogate data. PMID:23260570

Steinisch, Martin; Torke, Paul R; Haueisen, Jens; Hailer, Birgit; Grönemeyer, Dietrich; Van Leeuwen, Peter; Comani, Silvia

2013-02-01

113

Detection of Coronary Artery Stenoses by Contrast-Enhanced, Retrospectively Electrocardiographically-Gated, Multislice Spiral Computed Tomography  

Microsoft Academic Search

Background—Multislice spiral computed tomography (MSCT) with retrospectively ECG-gated image reconstruction permits coronary artery visualization. We investigated the method's ability to identify high-grade coronary artery stenoses and occlusions. Methods and Results—A total of 64 consecutive patients were studied by MSCT (4 31 mm cross-sections, 500-ms rotation, table feed 1.5 mm\\/rotation, intravenous contrast agent, retrospectively ECG-gated image reconstruction). All coronary arteries and

Stephan Achenbach; Tom Giesler; Dieter Ropers; Stefan Ulzheimer; Hans Derlien; Christoph Schulte; Evelyn Wenkel; Werner Moshage; Werner Bautz; Werner G. Daniel; Willi A. Kalender; Ulrich Baum

114

Can we predict failure in couple therapy early enough to enhance outcome?  

PubMed

Feedback to therapists based on systematic monitoring of individual therapy progress reliably enhances therapy outcome. An implicit assumption of therapy progress feedback is that clients unlikely to benefit from therapy can be detected early enough in the course of therapy for corrective action to be taken. To explore the possibility of using feedback of therapy progress to enhance couple therapy outcome, the current study tested whether weekly therapy progress could detect off-track clients early in couple therapy. In an effectiveness trial of couple therapy, 136 couples were monitored weekly on relationship satisfaction and an expert derived algorithm was used to attempt to predict eventual therapy outcome. As expected, the algorithm detected a significant proportion of couples who did not benefit from couple therapy at Session 3, but prediction was substantially improved at Session 4 so that eventual outcome was accurately predicted for 70% of couples, with little improvement of prediction thereafter. More sophisticated algorithms might enhance prediction accuracy, and a trial of the effects of therapy progress feedback on couple therapy outcome is needed. PMID:25574777

Pepping, Christopher A; Halford, W Kim; Doss, Brian D

2015-02-01

115

Haploinsufficiency of insulin gene enhancer protein 1 (ISL1) is associated with d-transposition of the great arteries  

PubMed Central

Congenital heart defects are the most common malformation, and are the foremost causes of mortality in the first year of life. Among congenital heart defects, conotruncal defects represent about 20% and are severe malformations with significant morbidity. Insulin gene enhancer protein 1 (ISL1) has been considered a candidate gene for conotruncal heart defects based on its embryonic expression pattern and heart defects induced in Isl1 knockout mice. Nevertheless no mutation of ISL1 has been reported from any human subject with a heart defect. From a population base of 974,579 births during 1999–2004, we used multiplex ligation-dependent probe amplification to screen for microdeletions/duplications of ISL1 among 389 infants with tetralogy of Fallot or d-transposition of the great arteries (d-TGA). We also sequenced all exons of ISL1. We identified a novel 20-kb microdeletion encompassing the entire coding region of ISL1, but not including either flanking gene, from an infant with d-TGA. We confirmed that the deletion was caused by nonhomologous end joining mechanism. Sequencing of exons of ISL1 did not reveal any subject with a novel nonsynonymous mutation. This is the first report of an ISL1 mutation of a child with a congenital heart defect. PMID:25077177

Osoegawa, Kazutoyo; Schultz, Kathleen; Yun, Kenneth; Mohammed, Nebil; Shaw, Gary M; Lammer, Edward J

2014-01-01

116

Nonrigid motion compensation in B-mode and contrast enhanced ultrasound image sequences of the carotid artery  

NASA Astrophysics Data System (ADS)

In this work, we investigate nonrigid motion compensation in simultaneously acquired (side-by-side) B-mode ultrasound (BMUS) and contrast enhanced ultrasound (CEUS) image sequences of the carotid artery. These images are acquired to study the presence of intraplaque neovascularization (IPN), which is a marker of plaque vulnerability. IPN quantification is visualized by performing the maximum intensity projection (MIP) on the CEUS image sequence over time. As carotid images contain considerable motion, accurate global nonrigid motion compensation (GNMC) is required prior to the MIP. Moreover, we demonstrate that an improved lumen and plaque differentiation can be obtained by averaging the motion compensated BMUS images over time. We propose to use a previously published 2D+t nonrigid registration method, which is based on minimization of pixel intensity variance over time, using a spatially and temporally smooth B-spline deformation model. The validation compares displacements of plaque points with manual trackings by 3 experts in 11 carotids. The average (+/- standard deviation) root mean square error (RMSE) was 99+/-74?m for longitudinal and 47+/-18?m for radial displacements. These results were comparable with the interobserver variability, and with results of a local rigid registration technique based on speckle tracking, which estimates motion in a single point, whereas our approach applies motion compensation to the entire image. In conclusion, we evaluated that the GNMC technique produces reliable results. Since this technique tracks global deformations, it can aid in the quantification of IPN and the delineation of lumen and plaque contours.

Carvalho, Diego D. B.; Akkus, Zeynettin; Bosch, Johan G.; van den Oord, Stijn C. H.; Niessen, Wiro J.; Klein, Stefan

2014-03-01

117

Reliability of contrast-enhanced ultrasound for the assessment of muscle perfusion in health and peripheral arterial disease.  

PubMed

We investigated the reliability of contrast-enhanced ultrasound (CEUS) in assessing calf muscle microvascular perfusion in health and disease. Response to a post-occlusive reactive hyperaemia test was repeated on two occasions >48 h apart in healthy young (28 ± 7 y) and elderly controls (70 ± 5 y), and in peripheral arterial disease patients (PAD, 69 ± 7 y; n = 10, 9 and 8 respectively). Overall, within-individual reliability was poor (coefficient of variation [CV] range: 15-87%); the most reliable parameter was time to peak (TTP, 15-48% CV). Nevertheless, TTP was twice as long in elderly controls and PAD compared to young (19.3 ± 10.4 and 22.0 ± 8.6 vs. 8.9 ± 6.2 s respectively; p < 0.01), and area under the curve for contrast intensity post-occlusion (a reflection of blood volume) was ?50% lower in elderly controls (p < 0.01 versus PAD and young). Thus, CEUS assessment of muscle perfusion during reactive hyperaemia demonstrated poor reliability, yet still distinguished differences between PAD patients, elderly and young controls. PMID:25308937

Thomas, Kate N; Cotter, James D; Lucas, Samuel J E; Hill, Brigid G; van Rij, André M

2015-01-01

118

Gadolinium-Enhanced Angiography for Diagnosis and Interventional Treatment of Subclavian Artery Stenosis Prior to Fistula Creation  

SciTech Connect

We report the use of gadolinium-based contrast agent for both diagnostic and interventional subclavian angiography in two azotemic patients, presenting with an asymptomatic, high-grade stenosis of the left subclavian artery, ipsilateral to the site of choice for native fistula creation. Angiographic imaging performed with diluted gadolinium-based contrast material was clear enough to perform successful subclavian artery stenting, resulting in normalization of the arterial blood pressure in the afferent artery of the dialysis fistula. Clinically, no decrease in residual renal function and no other complication were noted immediately or a longer period after the interventional treatment.

Termote, Bruno; Maleux, Geert, E-mail: geert.maleux@uz.kuleuven.ac.be; Heye, Sam [University Hospitals, Department of Radiology (Belgium); Fourneau, Inge [University Hospitals, Department of Vascular Surgery (Belgium); Claes, Kathleen [University Hospitals, Department of Nephrology (Belgium)

2008-07-15

119

Enhancement of dynein-mediated autophagosome trafficking and autophagy maturation by ROS in mouse coronary arterial myocytes.  

PubMed

Dynein-mediated autophagosome (AP) trafficking was recently demonstrated to contribute to the formation of autophagolysosomes (APLs) and autophagic flux process in coronary arterial myocytes (CAMs). However, it remains unknown how the function of dynein as a motor protein for AP trafficking is regulated under physiological and pathological conditions. The present study tested whether the dynein-mediated autophagy maturation is regulated by a redox signalling associated with lysosomal Ca(2+) release machinery. In primary cultures of CAMs, reactive oxygen species (ROS) including H2 O2 and O2 (-.) (generated by xanthine/xanthine oxidase) significantly increased dynein ATPase activity and AP movement, which were accompanied by increased lysosomal fusion with AP and APL formation. Inhibition of dynein activity by (erythro-9-(2-hydroxy-3-nonyl)adenine) (EHNA) or disruption of the dynein complex by dynamitin (DCTN2) overexpression blocked ROS-induced dynein activation, AP movement and APL formation, and resulted in an accumulation of AP along with a failed breakdown of AP. Antagonism of nicotinic acid adenine dinucleotide phosphate (NAADP)-mediated Ca(2+) signalling with NED-19 and PPADS abolished ROS-enhanced lysosomal Ca(2+) release and dynein activation in CAMs. In parallel, all these changes were also enhanced by overexpression of NADPH oxidase-1 (Nox1) gene in CAMs. Incubation with high glucose led to a marked O2 (-.) production compared with normoglycaemic CAMs, while Nox1 inhibitor ML117 abrogated this effect. Moreover, ML117 and NED-19 and PPADS significantly suppressed dynein activity and APL formation caused by high glucose. Taken together, these data suggest that ROS function as important players to regulate dynein-dependent AP trafficking leading to efficient autophagic maturation in CAMs. PMID:24912985

Xu, Ming; Li, Xiao-Xue; Chen, Yang; Pitzer, Ashley L; Zhang, Yang; Li, Pin-Lan

2014-11-01

120

Enhancement of dynein-mediated autophagosome trafficking and autophagy maturation by ROS in mouse coronary arterial myocytes  

PubMed Central

Dynein-mediated autophagosome (AP) trafficking was recently demonstrated to contribute to the formation of autophagolysosomes (APLs) and autophagic flux process in coronary arterial myocytes (CAMs). However, it remains unknown how the function of dynein as a motor protein for AP trafficking is regulated under physiological and pathological conditions. The present study tested whether the dynein-mediated autophagy maturation is regulated by a redox signalling associated with lysosomal Ca2+ release machinery. In primary cultures of CAMs, reactive oxygen species (ROS) including H2O2 and O2?. (generated by xanthine/xanthine oxidase) significantly increased dynein ATPase activity and AP movement, which were accompanied by increased lysosomal fusion with AP and APL formation. Inhibition of dynein activity by (erythro-9-(2-hydroxy-3-nonyl)adenine) (EHNA) or disruption of the dynein complex by dynamitin (DCTN2) overexpression blocked ROS-induced dynein activation, AP movement and APL formation, and resulted in an accumulation of AP along with a failed breakdown of AP. Antagonism of nicotinic acid adenine dinucleotide phosphate (NAADP)-mediated Ca2+ signalling with NED-19 and PPADS abolished ROS-enhanced lysosomal Ca2+ release and dynein activation in CAMs. In parallel, all these changes were also enhanced by overexpression of NADPH oxidase-1 (Nox1) gene in CAMs. Incubation with high glucose led to a marked O2?. production compared with normoglycaemic CAMs, while Nox1 inhibitor ML117 abrogated this effect. Moreover, ML117 and NED-19 and PPADS significantly suppressed dynein activity and APL formation caused by high glucose. Taken together, these data suggest that ROS function as important players to regulate dynein-dependent AP trafficking leading to efficient autophagic maturation in CAMs. PMID:24912985

Xu, Ming; Li, Xiao-Xue; Chen, Yang; Pitzer, Ashley L; Zhang, Yang; Li, Pin-Lan

2014-01-01

121

Enhanced Cellular Responses and Distinct Gene Profiles in Human Fetoplacental Artery Endothelial Cells under Chronic Low Oxygen1  

PubMed Central

ABSTRACT Fetoplacental endothelial cells are exposed to oxygen levels ranging from 2% to 8% in vivo. However, little is known regarding endothelial function within this range of oxygen because most laboratories use ambient air (21% O2) as a standard culture condition (SCN). We asked whether human umbilical artery endothelial cells (HUAECs) that were steadily exposed to the physiological chronic normoxia (PCN, 3% O2) for ?20–25 days differed in their proliferative and migratory responses to FGF2 and VEGFA as well as in their global gene expression compared with those in the SCN. We observed that PCN enhanced FGF2- and VEGFA-stimulated cell proliferation and migration. In oxygen reversal experiments (i.e., when PCN cells were exposed to SCN for 24 h and vice versa), we found that preexposure to 21% O2 decreased the migratory ability, but not the proliferative ability, of the PCN-HUAECs in response to FGF2 and VEGFA. These PCN-enhanced cellular responses were associated with increased protein levels of HIF1A and NOS3, but not FGFR1, VEGFR1, and VEGFR2. Microarray analysis demonstrated that PCN up-regulated 74 genes and down-regulated 86, 14 of which were directly regulated by hypoxia-inducible factors as evaluated using in silico analysis. Gene function analysis further indicated that the PCN-regulated genes were highly related to cell proliferation and migration, consistent with the results from our functional assays. Given that PCN significantly alters cellular responses to FGF2 and VEGFA as well as transcription in HUAECs, it is likely that we may need to reexamine the current cellular and molecular mechanisms controlling fetoplacental endothelial functions, which were largely derived from endothelial models established under ambient O2. PMID:24152727

Jiang, Yi-Zhou; Wang, Kai; Li, Yan; Dai, Cai-Feng; Wang, Ping; Kendziorski, Christina; Chen, Dong-Bao; Zheng, Jing

2013-01-01

122

Rastelli procedure for transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction. Early and late results in 41 patients (1971 to 1978).  

PubMed Central

Forty-one children with transposition of the great arteries, ventricular septal defect, and left ventricular outflow tract obstruction underwent a Rastelli operation between 1971 and 1978. A homograft valve preserved in an antibiotic solution and extended with A dacron tube was the conduit of choice. Alternatively, conduits with porcine heterografts or valves constructed from calf pericardium were used. They were positioned to the left of the aorta whenever possible. The intraventricular tunnel from the left ventricle to the aorta was constructed from Dacron velour. There were four early and seven late deaths. The last 13 consecutive patients have survived. Early deaths were related to unfavourable anatomy, conduit compression, and sepsis. Residual ventricular septal defects and postoperative infection were the main factors contributing to the late deaths. Images PMID:7193040

Moulton, A L; de Leval, M R; Macartney, F J; Taylor, J F; Stark, J

1981-01-01

123

Early decompressive surgery in malignant infarction of the middle cerebral artery: a pooled analysis of three randomised controlled trials  

Microsoft Academic Search

Summary Background Malignant infarction of the middle cerebral artery (MCA) is associated with an 80% mortality rate. Non-randomised studies have suggested that decompressive surgery reduces this mortality without increasing the number of severely disabled survivors. To obtain suffi cient data as soon as possible to reliably estimate the eff ects of decompressive surgery, results from three European randomised controlled trials

Katayoun Vahedi; Jeannette Hofmeijer; Eric Juettler; Eric Vicaut; Bernard George; Ale Algra; G Johan Amelink; Peter Schmiedeck; Stefan Schwab; Peter M Rothwell; Marie-Germaine Bousser; H Bart van der Worp; Werner Hacke

2007-01-01

124

Swan-Ganz catheter-induced rupture of the pulmonary artery: successful early management by transcatheter embolization.  

PubMed

An 84-year-old patient with severe aortic valve stenosis suffered Swan-Ganz catheter-induced massive pulmonary hemorrhage. Immediate therapeutic embolism of the segmental artery by using a liquid, tissue-adhesive, occlusive agent (isobutyl-2-cyanoacrylate) controlled bleeding. PMID:2317860

Jondeau, G; Lacombe, P; Rocha, P; Rigaud, M; Hardy, A; Bourdarias, J P

1990-03-01

125

Early and transient sodium-hydrogen exchanger isoform 1 inhibition attenuates subsequent cardiac hypertrophy and heart failure following coronary artery ligation.  

PubMed

Na(+)/H(+) exchanger 1 (NHE-1) inhibition attenuates the hypertrophic response and heart failure in various experimental models. As the hypertrophic program is rapidly initiated following insult, we investigated whether early and transient administration of a NHE-1 inhibitor will exert salutary effects on cardiomyocyte hypertrophy or heart failure using both in vitro and in vivo approaches. Neonatal cardiomyocytes were treated with the novel, potent, and highly specific NHE-1 inhibitor BIX (N-[4-(1-acetyl-piperidin-4-yl)-3-trifluoromethyl-benzoyl]-guanidine; 100 nM) for 1 hour in the presence of 10 µM phenylephrine, after which the cells were maintained for a further 23 hours in the absence of NHE-1 inhibition. One-hour treatment with the NHE-1 inhibitor prevented phenylephrine-induced hypertrophy, which was associated with prevention of activation of calcineurin, a key component of the hypertrophic process. Experiments were then performed in rats subjected to coronary artery ligation, in which the NHE-1 inhibitor was administered immediately after infarction for a 1-week period followed by a further 5 weeks of sustained coronary artery occlusion in the absence of drug treatment. This approach significantly attenuated left ventricular hypertrophy and improved both left ventricular systolic and diastolic dysfunction, which was also associated with inhibition of calcineurin activation. Our findings indicate that early and transient administration of an NHE-1 inhibitor bestows subsequent inhibition of cardiomyocyte hypertrophy in culture as well as cardiac hypertrophy and heart failure in vivo, suggesting a critical early NHE-1-dependent initiation of the hypertrophic program. The study also suggests a preconditioning-like phenomenon in preventing hypertrophy and heart failure by early and transient NHE-1 inhibition. PMID:25216745

Kili?, Ana; Huang, Cathy X; Rajapurohitam, Venkatesh; Madwed, Jeffrey B; Karmazyn, Morris

2014-12-01

126

The ionic products of bioactive glass particle dissolution enhance periodontal ligament fibroblast osteocalcin expression and enhance early mineralized tissue development.  

PubMed

This study resulted in enhanced collagen type 1 and osteocalcin expression in human periodontal ligament fibroblasts (hPDLF) when exposed to bioactive glass conditioned media that subsequently may promote early mineralized tissue development. Commercial Bioglass™ (45S5) and experimental bioactive coating glass (6P53-b), were used to make a glass conditioned media (GCM) for comparison to control medium. ICP-MS analysis showed increased concentrations of Ca(2+), PO(4) (3-), Si(4+), and Na(+), for 45S5 GCM and Mg(2+), K(+), Ca(2+), PO(4)(3-), Si(4+), and Na(+) for 6P53-b GCM (relative to control medium). Differentiating hPDLF cultures exposed to 45S5 and 6P53-b GCM showed enhanced expression of collagen type 1 (Col1?1, Col1?2), osteocalcin, and alkaline phosphatase gene expression. These GCM also enhanced osteocalcin protein expression. After 16 d of culture, 45S5 and 6P53-b GCM treated cells showed regions of deep red Alizarin staining, indicating increased Ca within their respective extracellular matrices (ECM), while control-treated cells did not exhibit these features. SEM analysis showed more developed ECM in GCM treated cultures, indicated by multiple tissue layering and abundant collagen fiber bundle formation, while control treated cells did not exhibit these features. SEM analysis showed polygonal structures suggestive of CaP in 45S5 GCM treated cultures. These results indicate the osteogenic potential of bioactive coating glass in periodontal bone defect filling applications. PMID:21548068

Varanasi, Venu G; Owyoung, Jeremy B; Saiz, Eduardo; Marshall, Sally J; Marshall, Grayson W; Loomer, Peter M

2011-08-01

127

Addendum to `numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system'  

USGS Publications Warehouse

Two numerical models to simulate an enhanced very early time electromagnetic (VETEM) prototype system that is used for buried-object detection and environmental problems are presented. In the first model, the transmitting and receiving loop antennas accurately analyzed using the method of moments (MoM), and then conjugate gradient (CG) methods with the fast Fourier transform (FFT) are utilized to investigate the scattering from buried conducting plates. In the second model, two magnetic dipoles are used to replace the transmitter and receiver. Both the theory and formulation are correct and the simulation results for the primary magnetic field and the reflected magnetic field are accurate.

Cui, T.J.; Chew, W.C.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.; Abraham, J.D.

2000-01-01

128

Microglia Enhance Neurogenesis and Oligodendrogenesis in the Early Postnatal Subventricular Zone  

PubMed Central

Although microglia have long been considered as brain resident immune cells, increasing evidence suggests that they also have physiological roles in the development of the normal CNS. In this study, we found large numbers of activated microglia in the forebrain subventricular zone (SVZ) of the rat from P1 to P10. Pharmacological suppression of the activation, which produces a decrease in levels of a number of proinflammatory cytokines (i.e., IL-1?, IL-6, TNF-?, and IFN-?) significantly inhibited neurogenesis and oligodendrogenesis in the SVZ. In vitro neurosphere assays reproduced the enhancement of neurogenesis and oligodendrogenesis by activated microglia and showed that the cytokines revealed the effects complementarily. These results suggest that activated microglia accumulate in the early postnatal SVZ and that they enhance neurogenesis and oligodendrogenesis via released cytokines. PMID:24501362

Shigemoto-Mogami, Yukari; Hoshikawa, Kazue; Goldman, James E.; Sekino, Yuko

2014-01-01

129

ETS factors regulate Vegf-dependent arterial specification.  

PubMed

Vegf signaling specifies arterial fate during early vascular development by inducing the transcription of Delta-like 4 (Dll4), the earliest Notch ligand gene expressed in arterial precursor cells. Dll4 expression precedes that of Notch receptors in arteries, and factors that direct its arterial-specific expression are not known. To identify the transcriptional program that initiates arterial Dll4 expression, we characterized an arterial-specific and Vegf-responsive enhancer of Dll4. Our findings demonstrate that Notch signaling is not required for initiation of Dll4 expression in arteries and suggest that Notch instead functions as a maintenance factor. Importantly, we find that Vegf signaling activates MAP kinase (MAPK)-dependent E26 transformation-specific sequence (ETS) factors in the arterial endothelium to drive expression of Dll4 and Notch4. These findings identify a Vegf/MAPK-dependent transcriptional pathway that specifies arterial identity by activating Notch signaling components and illustrate how signaling cascades can modulate broadly expressed transcription factors to achieve tissue-specific transcriptional outputs. PMID:23830865

Wythe, Joshua D; Dang, Lan T H; Devine, W Patrick; Boudreau, Emilie; Artap, Stanley T; He, Daniel; Schachterle, William; Stainier, Didier Y R; Oettgen, Peter; Black, Brian L; Bruneau, Benoit G; Fish, Jason E

2013-07-15

130

Musical training during early childhood enhances the neural encoding of speech Dana L. Strait a,b  

E-print Network

Musical training during early childhood enhances the neural encoding of speech in noise Dana L propose that musicians' perceptual and neural enhance- ments are driven in a top-down manner to improve a child's access to a target signal in noise. Given adult musicians' perceptual and neural speech

131

Pre-dawn stomatal opening does not substantially enhance early-morning photosynthesis in Helianthus annuus.  

PubMed

Most C3 plant species have partially open stomata during the night especially in the 3-5 h before dawn. This pre-dawn stomatal opening has been hypothesized to enhance early-morning photosynthesis (A) by reducing diffusion limitations to CO2 at dawn. We tested this hypothesis in cultivated Helianthus annuus using whole-shoot gas exchange, leaf level gas exchange and modelling approaches. One hour pre-dawn low-humidity treatments were used to reduce pre-dawn stomatal conductance (g). At the whole-shoot level, a difference of pre-dawn g (0.40 versus 0.17 mol m(-2) s(-1)) did not significantly affect A during the first hour after dawn. Shorter term effects were investigated with leaf level gas exchange measurements and a difference of pre-dawn g (0.10 versus 0.04 mol m(-2) s(-1)) affected g and A for only 5 min after dawn. The potential effects of a wider range of stomatal apertures were explored with an empirical model of the relationship between A and intercellular CO2 concentration during the half-hour after dawn. Modelling results demonstrated that even extremely low pre-dawn stomatal conductance values have only a minimal effect on early-morning A for a few minutes after dawn. Thus, we found no evidence that pre-dawn stomatal opening enhances A. PMID:24895756

Auchincloss, Lisa; Easlon, Hsien M; Levine, Diedre; Donovan, Lisa; Richards, James H

2014-06-01

132

Complex interventional procedures for the management of early postoperative left main coronary artery embolism after bioprosthetic aortic valve insertion.  

PubMed

The incidence of calcified debris coronary embolism after aortic valve replacement (AVR) with a bioprosthesis is a rare but potentially life-threatening condition. We sought to describe a case of immediate postoperative left main coronary artery embolism, resulting to severe acute coronary syndrome and cardiogenic shock, after aortic valve surgery due to severe aortic valve stenosis, with the use of bioprosthesis. Complex interventional procedures and possible diagnostic challenges are being described. PMID:21241978

Gavrielatos, Gerasimos; Buttner, Heinz J; Lehane, Con; Neumann, Franz J

2011-01-01

133

Enhancement of the pulmonary arteries and thoracic aorta: comparison of a biphasic contrast injection and fixed delay protocol with a monophasic injection and a timing bolus protocol.  

PubMed

The definitive diagnosis of pulmonary embolism, a significant cause of morbidity and mortality, relies on imaging. In this study, we compare the conventional computed tomography pulmonary angiogram (CTPA) protocol to a double-rule out CT angiogram (DRO CTA) protocol in terms of vascular enhancement, radiation dose, and contrast volume delivered. The CTPA protocol involves injection of a timing bolus for localization of the pulmonary artery, whereas the DRO CTA protocol involves a biphasic contrast. We analyzed 248 consecutive CTPA studies and 242 consecutive DRO CTA studies. Vessel enhancement using region of interest (ROI) measurements, radiation dose delivered, and total contrast volume administered was recorded. The enhancement of all vessels measured was statistically significantly higher with the biphasic DRO CTA protocol than the CTPA protocol. The difference in mean vascular enhancement for the two protocols was greatest in the descending aorta (DA, P?artery (MPA, P?=?0.001). The percent of studies with vascular enhancement ?250 Hounsfield units (HU) was significantly greater in all vascular beds except the MPA when the DRO CTA protocol was used. Studies performed with the DRO CTA protocol led to less radiation exposure and used less contrast than those performed with the CTPA protocol (P?arterial and aortic vessels studied, with no greater delivery of radiation or contrast, than the monophasic CTPA protocol. PMID:25228282

Cornea, Anda M; McCullough, Brendan J; Mitsumori, Lee M; Gunn, Martin L D

2014-09-17

134

Coronary Arteries  

MedlinePLUS

... and animations for grades K-6. The Coronary Arteries | Share Coronary Circulation The heart muscle, like every ... into two main coronary blood vessels (also called arteries). These coronary arteries branch off into smaller arteries, ...

135

Early markers of cognitive enhancement: developing an implicit measure of cognitive performance.  

PubMed

There is intense interest in the development of effective cognitive enhancing drugs which would have therapeutic application across a number of neurological and psychological disorders including dementia, schizophrenia and depression. However, development in this area has been limited by the absence of sensitive biomarkers which can be used to detect and refine therapeutic-like action in phase 1 clinical studies. The aim of the present study was therefore to develop a measure of cognition relevant to the action of candidate cognitive enhancers which might be sensitive to pharmacological manipulation in healthy volunteers. Healthy volunteers (n?=?34) were randomised to receive a single dose of modafinil (100 mg) or placebo. Five hours post dose, attentional flexibility in learning was assessed using a novel implicit learning task. Volunteers also completed an auditory digit span task and visual analogue scales (VAS). Modafinil increased alertness as measured by the VAS. In the implicit learning task, modafinil enhanced learning rates in terms of both accuracy and reaction time, suggesting an increase in implicit rule learning. These results suggest that the novel learning task should be explored as a biomarker of early cognitive improvement which could be more sensitive than conventional measures. PMID:23820927

Pringle, Abbie; Browning, Michael; Parsons, Elizabeth; Cowen, Phil J; Harmer, Catherine J

2013-12-01

136

Manganese-enhanced MRI reveals early-phase radiation-induced cell alterations in vivo.  

PubMed

For tumor radiotherapy, the in vivo detection of early cellular responses is important for predicting therapeutic efficacy. Mn(2+) is used as a positive contrast agent in manganese-enhanced MRI (MEMRI) and is expected to behave as a mimic of Ca(2+) in many biologic systems. We conducted in vitro and in vivo MRI experiments with Mn(2+) to investigate whether MEMRI can be used to detect cell alterations as an early-phase tumor response after radiotherapy. Colon-26 cells or a subcutaneously grafted colon-26 tumor model were irradiated with 20 Gy of X-rays. One day after irradiation, a significant augmentation of G2-M-phase cells, indicating a cell-cycle arrest, was observed in the irradiated cells in comparison with the control cells, although both early and late apoptotic alterations were rarely observed. The MEMRI signal in radiation-exposed tumor cells (R1: 0.77 ± 0.01 s(-1)) was significantly lower than that in control cells (R1: 0.82 ± 0.01 s(-1)) in vitro. MEMRI signal reduction was also observed in the in vivo tumor model 24 hours after irradiation (R1 of radiation: 0.97 ± 0.02 s(-1), control: 1.10 ± 0.02 s(-1)), along with cell-cycle and proliferation alterations identified with immunostaining (cyclin D1 and Ki-67). Therefore, MEMRI after tumor radiotherapy was successfully used to detect cell alterations as an early-phase cellular response in vitro and in vivo. PMID:23695553

Saito, Shigeyoshi; Hasegawa, Sumitaka; Sekita, Aiko; Bakalova, Rumiana; Furukawa, Takako; Murase, Kenya; Saga, Tsuneo; Aoki, Ichio

2013-06-01

137

Requirements for enhanced transgene expression by untranslated sequences from the human cytomegalovirus immediate-early gene.  

PubMed Central

BACKGROUND: The cytomegalovirus immediate early (CMV IE) promoter has been widely used for heterologous expression. Further enhancements of gene expression from this potent promoter may allow for the development of improved gene transfer strategies. We aimed to determine whether inclusion of the first exon (5' untranslated) and first intron of the CMV IE gene would increase heterologous transgene expression in primary target cells and to determine the sequences required for any observed increases. MATERIALS AND METHODS: Comparisons of reporter gene expression were made following transient transfection of vascular smooth muscle cells (VSMCs) with plasmids containing the first exon and intron from the CMV IE gene or deletional mutations. Comparisons were also made using a heterologous promoter (RSV). RESULTS: Gene expression from the CMV IE promoter was increased 5.7-fold in VSMC with the inclusion of the first exon and intron. Similar increases were seen with other target cells and from the heterologous RSV promoter. This increase was associated with an increase in steady-state mRNA. Deletion analyses demonstrated that the enhancement was dependent on the presence of the 5' portion of the first exon while deletion of large segments within the intron was associated with similar levels of expression compared with the parental plasmid. CONCLUSIONS: Inclusion of the first exon and intron from the CMV IE gene increases expression from the CMV IE promoter. This enhancement is seen with the heterologous RSV promoter and is associated with an increase in steady-state mRNA. Deletion analyses suggest that this enhancement is associated with inclusion of sequences within the 5' portion of the first exon and inclusion of an intron. Images Fig. 1 Fig. 3 PMID:9932107

Simari, R. D.; Yang, Z. Y.; Ling, X.; Stephan, D.; Perkins, N. D.; Nabel, G. J.; Nabel, E. G.

1998-01-01

138

Coronary pressure notch: an early non-hyperemic visual indicator of the physiologic significance of a coronary artery stenosis.  

PubMed

The disappearance of a dichrotic notch on the peripheral arterial pulse wave has been associated with significant peripheral vascular disease. A similar observation has not been reported in the distal coronary pressure waveform. The purpose of this study was to investigate the significance of a coronary pressure notch distal to a coronary stenosis and its relationship to fractional flow reserve. Ninety-seven patients with 131 angiographically indeterminate lesions (40-80% diameter narrowing) underwent FFR measurements for physiological significance. Hemodynamic tracings were recorded prior to the administration of adenosine and visually analyzed for the presence or absence of a dicrotic notch in the distal coronary artery pressure tracing. The stenoses were then divided into two groups based on the presence or absence of a notch. Of the 54 lesions without a distal coronary pressure notch, 31 had a FFR greater than or equal to 0.75 and of the 77 lesions with a notch, 75 had a FFR greater than or equal to 0.76. The sensitivity and specificity of a pressure notch was 94% and 74%, respectively, with positive and negative predictive values of 57% and 97%, respectively. The presence of a distal coronary pressure notch was predictive of a FFR greater than or equal to 0.76. The distal dicrotic pressure notch may be used as an additional parameter without requiring hyperemia for FFR measurements of uncertain clinical significance. PMID:15550728

Holmes, David; Velappan, Priya; Kern, Morton J

2004-11-01

139

Early Detection of Therapeutic Response to Hepatic Arterial Infusion Chemotherapy of Liver Metastases from Colorectal Cancer Using Diffusion-Weighted MR Imaging  

SciTech Connect

The purpose of this study was to investigate whether diffusion-weighted magnetic resonance imaging (DWI) is useful for early detection of the response of hepatic colorectal metastases to hepatic arterial infusion chemotherapy (HAIC) with 5-fluorouracil (5-FU). The subjects were 12 patients with hepatic colorectal metastases. The indwelling catheter for HAIC was placed in the hepatic artery, and 1000 mg/m{sup 2} 5-FU was given repeatedly once a week. DWI was performed before and 9 days after HAIC. The minimum and mean apparent diffusion coefficient (ADC) values (minADC and meanADC) were measured. The relative change in ADC values (%ADC) and the relative change in tumor size on follow-up CT after 3 months (reduction ratio) were determined. Liver metastases were divided into two groups, responder and nonresponder. The correlation between %ADC and reduction ratio was determined, and %ADC was compared between the two groups. Eleven patients successfully completed HAIC over the 3-month period; 48 metastatic lesions were evaluated. Positive correlations were observed for relative change between %minADC and reduction ratio (r = 0.709) and between %meanADC and reduction ratio (r = 0.536). Both %minADC and %meanADC were significantly greater in the responder group than in the nonresponder group. With the threshold determined as < 3.5%, the receiver-operating curve analysis showed higher sensitivity and specificity values for %minADC (100% and 92.6%, respectively) than for %meanADC (66.7% and 74.1%, respectively). In conclusion, the relative change in minimum ADC values on DWI may be useful for early detection of the response of liver metastases to HAIC with 5-FU.

Marugami, Nagaaki; Tanaka, Toshihiro, E-mail: toshihir@bf6.so-net.ne.jp; Kitano, Satoru [Nara Medical University, Department of Radiology (Japan); Hirohashi, Shinji [Osaka Gyomeikan Hospital, Department of Radiology (Japan); Nishiofuku, Hideyuki [Nara Medical University, Department of Radiology (Japan); Takahashi, Aki; Sakaguchi, Hiroshi [Nara Prefectural Mimuro Hospital, Department of Radiology (Japan); Matsuoka, Masaki; Otsuji, Toshio [Dongo Hospital, Department of Gastrointestinal Medicine (Japan); Takahama, Junko; Higashiura, Wataru; Kichikawa, Kimihiko [Nara Medical University, Department of Radiology (Japan)

2009-07-15

140

On-versus Off-Pump Coronary Artery Bypass Grafting: No Difference in Early Postoperative Kidney Function Based on TNF-? or C-Reactive Protein  

PubMed Central

Background/Aims There are controversial data about renal function following off-pump coronary artery bypass grafting (CABG). The present study aimed to evaluate renal function changes 24 h after on- and off-pump CABG, as well as renal function correlated with high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor-? (TNF-?). Methods Ninety patients with coronary artery disease referred to our center for CABG from July 2006 to November 2007 were enrolled in the study. Patients were equally and randomly divided in two groups, on- and off-pump. Serum levels of creatinine (Cr), blood urea nitrogen, creatinine clearance (CrCl), hs-CRP, and TNF-? were determined immediately before and 24 h after surgery. Results Cr and CrCl changes after surgery were not significantly different between the two groups; however, blood urea nitrogen levels after surgery were significantly higher in the on-pump group (p = 0.035). No statistically significant difference was noted between the two groups in terms of changes in levels of hs-CRP and TNF-? (p = 0.350 and 0.805, respectively). The changes in CrCl levels had no significant correlation with hs-CRP and TNF-?. Conclusions The early Cr and CrCl levels after surgery are not significantly different in on- and off-pump groups. The early renal function after on- or off-pump CABG is not correlated with the levels of inflammatory markers including hs-CRP and TNF-?. PMID:22969775

Nezami, Nariman; Djavadzadegan, Hassan; Tabatabaie-Adl, Haleh; Hamdi, Amir; Ghobadi, Kazem; Ghorashi, Sona; Hajhosseini, Babak

2012-01-01

141

Enhancement of plasmid DNA transformation efficiencies in early stationary phase yeast cell cultures  

PubMed Central

Chemical-based methods have been developed for transformation of DNA into log phase cells of the budding yeast Saccharomyces cerevisiae with high efficiency. Transformation of early stationary phase cells, e.g., cells grown in overnight liquid cultures or as colonies on plates, is less efficient than log phase cells but is simpler and more adaptable to high throughput projects. In this study we have tested different approaches for transformation of early stationary phase cell cultures and identified a method utilizing polyethylene glycol (PEG), lithium acetate and dimethyl sulfoxide (DMSO) as most efficient. Plasmid DNA transformations using this method could be improved modestly by allowing cells to recover from the chemical treatment in rich broth before plating to selective media. Strong increases in transformation efficiencies were observed when cells were treated briefly with dithiothreitol (DTT). Tests using several different yeast strain backgrounds indicated that DTT treatment could enhance transformation efficiencies by up to 40-fold. Evaluation of multiple parameters affecting the efficiency of the method led to development of an optimized protocol achieving >50,000 transformants per µg DNA in most backgrounds tested. PMID:23483586

Tripp, Jennifer DeMars; Lilley, Jennifer L.; Wood, Whitney N.; Lewis, L. Kevin

2013-01-01

142

Emphysema early diagnosis using X-ray diffraction enhanced imaging at synchrotron light source  

PubMed Central

Background Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide, and emphysema is a common component of COPD. Currently, it is very difficult to detect early stage emphysema using conventional radiographic imaging without contrast agents, because the change in X-ray attenuation is not detectable with absorption-based radiography. Compared with the absorption-based CT, phase contrast imaging has more advantages in soft tissue imaging, because of its high spatial resolution and contrast. Methods In this article, we used diffraction enhanced imaging (DEI) method to get the images of early stage emphysematous and healthy samples, then extract X-ray absorption, refraction, and ultra-small-angle X-ray scattering (USAXS) information from DEI images using multiple image radiography (MIR). We combined the absorption image with the USAXS image by a scatter plot. The critical threshold in the scatter plot was calibrated using the linear discriminant function in the pattern recognition. Results USAXS image was sensitive to the change of tissue micro-structure, it could show the lesions which were invisible in the absorption image. Combined with the absorption-based image, the USAXS information enabled better discrimination between healthy and emphysematous lung tissue in a mouse model. The false-color images demonstrated that our method was capable of classifying healthy and emphysematous tissues. Conclusion Here we present USAXS images of early stage emphysematous and healthy samples, where the dependence of the USAXS signal on micro-structures of biomedical samples leads to improved diagnosis of emphysema in lung radiographs. PMID:24952622

2014-01-01

143

Endothelium-dependent relaxation and hyperpolarization evoked by bradykinin in canine coronary arteries: enhancement by exercise-training.  

PubMed Central

1. Kinins, which are produced locally in arterial walls, stimulate the release of endothelium-derived vasodilator substances. Therefore, they may participate in the metabolic adaptation to chronic exercise that occurs in the coronary circulation. Experiments were designed to compare the reactivity to bradykinin in coronary arteries isolated from sedentary and exercised-trained dogs (for 8-10 weeks). 2. The organ chambers used in this study were designed for measurement of isometric tension and cell membrane potential with glass microelectrodes. Rings of canine isolated coronary arteries with endothelium were suspended in the organ chambers filled with modified Krebs-Ringer bicarbonate solution (37 degrees C, gassed with 5% CO2 in 95 O2), and were all treated with indomethacin to prevent interference from prostaglandins. 3. Bradykinin evoked concentration-dependent relaxations of the coronary arteries. However, the kinin was significantly less potent in relaxing coronary arteries from the sedentary dogs than those from the trained ones. 4. In the presence of NG-nitro-L-arginine (an inhibitor of nitric oxide synthases), concentration-relaxation curves to bradykinin were shifted to the right in both types of preparations. Nonetheless, the peptide was still significantly more potent in arteries from exercise-trained animals. 5. In the electrophysiological experiments, concentration-hyperpolarization curves to bradykinin obtained in arteries from sedentary dogs were also significantly to the right of those in vessels from exercise-trained animals. Thus, in arteries from exercised animals, bradykinin more potently evoked the release of both nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF). 7. The angiotensin converting enzyme (ACE)-inhibitor, perindoprilat, shifted to the left the concentration-relaxation curves to bradykinin obtained under control conditions and in the presence of NG-nitro-L-arginine. The concentration-hyperpolarization curves to bradykinin were also shifted to the left by perindoprilat. The shift induced by the ACE-inhibitor in either type of preparation was not significantly different. 8. These findings demonstrate that exercise-training augments the sensitivity of the coronary artery of the dog to the endothelium-dependent effects of bradykinin. This sensitization to bradykinin may reflect an increased role of both NO and EDHF, and is not the consequence of differences in ACE activity in the receptor compartment. PMID:8821528

Mombouli, J. V.; Nakashima, M.; Hamra, M.; Vanhoutte, P. M.

1996-01-01

144

The human cytomegalovirus major immediate-early distal enhancer region is required for efficient viral replication and immediate-early gene expression.  

PubMed

The human cytomegalovirus (HCMV) major immediate-early (MIE) genes, encoding IE1 p72 and IE2 p86, are activated by a complex enhancer region (base positions -65 to -550) that operates in a cell type- and differentiation-dependent manner. The expression of MIE genes is required for HCMV replication. Previous studies analyzing functions of MIE promoter-enhancer segments suggest that the distal enhancer region variably modifies MIE promoter activity, depending on cell type, stimuli, or state of differentiation. To further understand the mechanism by which the MIE promoter is regulated, we constructed and analyzed several different recombinant HCMVs that lack the distal enhancer region (-300 to -582, -640, or -1108). In human fibroblasts, the HCMVs without the distal enhancer replicate normally at high multiplicity of infection (MOI) but replicate poorly at low MOI in comparison to wild-type virus (WT) or HCMVs that lack the neighboring upstream unique region and modulator (-582 or -640 to -1108). The growth aberrancy was normalized after restoring the distal enhancer in a virus lacking this region. For HCMVs without a distal enhancer, the impairment in replication at low MOI corresponds to a deficiency in production of MIE RNAs compared to WT or virus lacking the unique region and modulator. An underproduction of viral US3 RNA was also evident at low MOI. Whether lower production of IE1 p72 and IE2 p86 causes a reduction in expression of the immediate-early (IE) class US3 gene remains to be determined. We conclude that the MIE distal enhancer region possesses a mechanism for augmenting viral IE gene expression and genome replication at low MOI, but this regulatory function is unnecessary at high MOI. PMID:10644329

Meier, J L; Pruessner, J A

2000-02-01

145

The Human Cytomegalovirus Major Immediate-Early Distal Enhancer Region Is Required for Efficient Viral Replication and Immediate-Early Gene Expression  

PubMed Central

The human cytomegalovirus (HCMV) major immediate-early (MIE) genes, encoding IE1 p72 and IE2 p86, are activated by a complex enhancer region (base positions -65 to -550) that operates in a cell type- and differentiation-dependent manner. The expression of MIE genes is required for HCMV replication. Previous studies analyzing functions of MIE promoter-enhancer segments suggest that the distal enhancer region variably modifies MIE promoter activity, depending on cell type, stimuli, or state of differentiation. To further understand the mechanism by which the MIE promoter is regulated, we constructed and analyzed several different recombinant HCMVs that lack the distal enhancer region (-300 to -582, -640, or -1108). In human fibroblasts, the HCMVs without the distal enhancer replicate normally at high multiplicity of infection (MOI) but replicate poorly at low MOI in comparison to wild-type virus (WT) or HCMVs that lack the neighboring upstream unique region and modulator (-582 or -640 to -1108). The growth aberrancy was normalized after restoring the distal enhancer in a virus lacking this region. For HCMVs without a distal enhancer, the impairment in replication at low MOI corresponds to a deficiency in production of MIE RNAs compared to WT or virus lacking the unique region and modulator. An underproduction of viral US3 RNA was also evident at low MOI. Whether lower production of IE1 p72 and IE2 p86 causes a reduction in expression of the immediate-early (IE) class US3 gene remains to be determined. We conclude that the MIE distal enhancer region possesses a mechanism for augmenting viral IE gene expression and genome replication at low MOI, but this regulatory function is unnecessary at high MOI. PMID:10644329

Meier, Jeffery L.; Pruessner, Jonathan A.

2000-01-01

146

Complementary tumor vascularity imaging in a single PET-CT routine using FDG early dynamic blood flow and contrast-enhanced CT texture analysis  

NASA Astrophysics Data System (ADS)

A feasibility study of improved PET-CT tumor imaging approach is presented. A single PET-CT routine includes three different techniques: 18F-FDG early dynamic blood flow intended for perfusion assessment; standard late 18F-FDG uptake; and high-resolution contrast-enhanced CT enabling tissue texture analysis. Both PET protocols utilize the same single standard radiotracer dose administration. Quantitative volumetric arterial perfusion maps are derived from the reconstructed dynamic PET images corresponding to successive acquisition time intervals of 3 seconds only. For achieving high accuracy, the analysis algorithm differentiates the first-pass arterial flow from other interfering dynamic effects, and a noise reduction scheme based on adaptive total-variation minimization aims to provide appreciable quantitative map in physical conditions of high noise and low spatial resolution. The CT texture analysis comprises a practical and robust method for generating volumetric tissue irregularity maps. A local map value is represented by the entropy function which is derived from a weighted co-occurrence matrix histogram of the corresponding image voxel three-dimensional vicinity. Unique entropy scaling scheme and parameter optimization process, as well as appropriate scaling for varying image noise levels and contrast agent concentrations, improve the results toward quantitative absolute measure with respect to diverse scanning conditions and key analysis parameters. Representative imaging results are demonstrated on several clinical cases involving different organs and cancer types. In these cases, significant tumor characterization relative to the normal surrounding tissues is seen on the quantitative maps of all three imaging techniques. This proof of concept can lead the way to a new practical diagnostic imaging application.

Carmi, Raz; Yefremov, Nikolay; Bernstine, Hanna; Groshar, David

2014-03-01

147

Can late gadolinium enhancement by cardiovascular magnetic resonance identify coronary artery disease as the etiology of new onset congestive heart failure?  

Microsoft Academic Search

Background  New left ventricular systolic dysfunction affects 500,000 Americans and coronary artery disease (CAD) is responsible for two-thirds\\u000a of cases. Identifying CAD has both prognostic and therapeutic implications. We evaluated the ability of late gadolinium enhancement\\u000a (LGE) by cardiovascular magnetic resonance imaging (CMR) to detect CAD as the etiology of recent onset congestive heart failure\\u000a (CHF).\\u000a \\u000a \\u000a \\u000a Methods  CMR and LGE were performed

Brian J. Schietinger; Szilard Voros; David C. Isbell; Craig H. Meyer; John M. Christopher; Christopher M. Kramer

2007-01-01

148

Involvement of H2O2 in superoxide-dismutase-induced enhancement of endothelium-dependent relaxation in rabbit mesenteric resistance artery  

PubMed Central

The mechanism underlying the enhancement by superoxide dismutase (SOD) of endothelium-dependent relaxation was investigated in rabbit mesenteric resistance arteries. SOD (200 U ml?1) increased the production of H2O2 in smooth muscle cells (as indicated by the use of an H2O2-sensitive fluorescent dye). Neither SOD nor catalase (400 U ml?1) modified either the resting membrane potential or the hyperpolarization induced by acetylcholine (ACh, 1 ?M) in smooth muscle cells. In arteries constricted with noradrenaline, the endothelium-dependent relaxation induced by ACh (0.01–1 ?M) was enhanced by SOD (200 U ml?1) (P<0.01). This action of SOD was inhibited by L-NG-nitroarginine (nitric oxide (NO)-synthase inhibitor) but not by either charybdotoxin+apamin (Ca2+-activated-K+-channel blockers) or diclofenac (cyclooxygenase inhibitor). Neither ascorbate (50 ?M) nor tiron (0.3 mM), superoxide scavengers, had any effect on the ACh-induced relaxation, but each attenuated the enhancing effect of SOD on the ACh-induced relaxation. Similarly, catalase (400 U ml?1) inhibited the effect of SOD without changing the ACh-induced relaxation. In endothelium-denuded strips constricted with noradrenaline, SOD enhanced the relaxation induced by the NO donor 1-hydroxy-2-oxo-3-(N-methyl-3-aminopropyl)-3-methyl-1-triazene (NOC-7) (P<0.05). Ascorbate and catalase each attenuated this effect of SOD. H2O2 (1 ?M) enhanced the relaxation on the noradrenaline contraction induced by NOC-7 and that induced by 8-bromo-cGMP, a membrane-permeable analogue of guanosine 3?,5? cyclic monophosphate (cGMP). SOD had no effect on cGMP production, whether measured in endothelium-intact strips following an application of ACh (0.1 ?M) or in endothelium-denuded strips following an application of NOC-7 (0.1 ?M). It is suggested that in rabbit mesenteric resistance arteries, SOD increases the ACh-induced, endothelium-dependent relaxation by enhancing the action of NO in the smooth muscle via its H2O2-producing action (rather than via a superoxide-scavenging action). PMID:12770950

Itoh, Takeo; Kajikuri, Junko; Hattori, Tomonori; Kusama, Nobuyoshi; Yamamoto, Tamao

2003-01-01

149

Acute psychological and physical stress transiently enhances brachial artery flow-mediated dilation stimulated by exercise-induced increases in shear stress.  

PubMed

Exercise elevates conduit artery shear stress and stimulates flow-mediated dilation (FMD). However, little is known regarding the impact of acute psychological and physical stress on this response. The purpose of this study was to examine the impact of the Trier Social Stress Test (TSST (speech and arithmetic tasks)) and a cold pressor test (CPT) with and without social evaluation (SE) on exercise-induced brachial artery FMD (EX-FMD). A total of 59 healthy male subjects were randomly assigned to 1 of 3 conditions: TSST, CPT, or CPT with SE. During 6 min of handgrip exercise, brachial artery EX-FMD was assessed before and 15 and 35 min poststress with echo and Doppler ultrasound. Shear stress was estimated as shear rate, calculated as brachial artery mean blood velocity/brachial artery diameter. Results are means ± SD. All conditions elicited significant physiological stress responses. Salivary cortisol increased from 4.6 ± 2.4 nmol/L to 10.0 ± 5.0 nmol/L (p < 0.001; condition effect: p = 0.292). Mean arterial pressure increased from 98.6 ± 12.1 mm Hg to 131.9 ± 18.7 mm Hg (p < 0.001; condition effect: p = 0.664). Exercise shear rate did not differ between conditions (p = 0.592), although it was modestly lower poststress (prestress: 72.3 ± 4.5 s(-1); 15 min poststress: 70.8 ± 5.4 s(-1); 35 min poststress: 70.6 ± 6.1 s(-1); trial effect: p = 0.011). EX-FMD increased from prestress to 15 min poststress in all conditions (prestress: 6.2% ± 2.8%; 15 min poststress: 7.9% ± 3.2%; 35 min poststress: 6.6% ± 2.9%; trial effect: p < 0.001; condition effect: p = 0.611). In conclusion, all conditions elicited similar stress responses that transiently enhanced EX-FMD. This response may help to support muscle perfusion during stress. PMID:24921439

Szijgyarto, Ingrid C; Poitras, Veronica J; Gurd, Brendon J; Pyke, Kyra E

2014-08-01

150

Is social isolation/alienation confounded with, and non-independent of, emotional distress in its association with early onset of coronary artery disease?  

PubMed

Both emotional distress (ED) and social isolation/alienation (SI/A) have been found to prospectively predict adverse cardiac events, but few studies have tested the confounding/redundancy of these measures as correlates/predictors of outcomes. In this study, 163 patients with documented coronary artery disease (CAD) were interviewed for multiple indices of SI/A and administered the Symptom Checklist 90 - Revised (SCL90R). A spouse or friend provided an independent rating of ED using the spouse/friend version of the Ketterer Stress Symptom Frequency Checklist (KSSFC). The measures of ED and SI/A covaried. All three scales from the KSSFC (depression, anxiety, and "AIAI" - aggravation, irritation, anger, and impatience), and three scales from the SCL90R (anxiety, depression, and psychoticism), were associated with early Age at Initial Diagnosis (AAID) of CAD. Neither three scales derived from the SCL90R (shyness, feeling abused, and feeling lonely) nor the interview indices of SI/A (married, living alone, having a confidant, self description as a lone wolf, and self-description as lonely) were associated with early AAID. Thus, it is concluded that the present results indicate that ED and SI/A are confounded and that, even when tested head-to-head in a multivariate analysis, only ED is associated with AAID. PMID:21328150

Ketterer, Mark; Rose, Benjamin; Knysz, Walter; Farha, Amjad; Deveshwar, Sangita; Schairer, John; Keteyian, Steven J

2011-03-01

151

Quantitative assessment of regional cerebral blood flow by dynamic susceptibility contrast-enhanced MRI, without the need for arterial blood signals  

NASA Astrophysics Data System (ADS)

In dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI), an arterial input function (AIF) is usually obtained from a time-concentration curve (TCC) of the cerebral artery. This study was aimed at developing an alternative technique for reconstructing AIF from TCCs of multiple brain regions. AIF was formulated by a multi-exponential function using four parameters, and the parameters were determined so that the AIF curves convolved with a model of tissue response reproduced the measured TCCs for 20 regions. Systematic simulations were performed to evaluate the effects of possible error sources. DSC-MRI and positron emission tomography (PET) studies were performed on 14 patients with major cerebral artery occlusion. Cerebral blood flow (CBF) images were calculated from DSC-MRI data, using our novel method alongside conventional AIF estimations, and compared with those from 15O-PET. Simulations showed that the calculated CBF values were sensitive to variations in the assumptions regarding cerebral blood volume. Nevertheless, AIFs were reasonably reconstructed for all patients. The difference in CBF values between DSC-MRI and PET was -2.2 ± 7.4 ml/100 g/min (r = 0.55, p < 0.01) for our method, versus -0.2 ± 8.2 ml/100 g/min (r = 0.47, p = 0.01) for the conventional method. The difference in the ratio of affected to unaffected hemispheres between DSC-MRI and PET was 0.07 ± 0.09 (r = 0.82, p < 0.01) for our method, versus 0.07 ± 0.09 (r = 0.83, p < 0.01) for the conventional method. The contrasts in CBF images from our method were the same as those from the conventional method. These findings suggest the feasibility of assessing CBF without arterial blood signals.

Enmi, Jun-ichiro; Kudomi, Nobuyuki; Hayashi, Takuya; Yamamoto, Akihide; Iguchi, Satoshi; Moriguchi, Tetsuaki; Hori, Yuki; Koshino, Kazuhiro; Zeniya, Tsutomu; Shah, Nadim Jon; Yamada, Naoaki; Iida, Hidehiro

2012-12-01

152

Value of Single-Dose Contrast-Enhanced Magnetic Resonance Angiography Versus Intraarterial Digital Subtraction Angiography in Therapy Indications in Abdominal and Iliac Arteries  

SciTech Connect

The objective of the study was to prove the value of single-dose contrast-enhanced magnetic resonance angiography [three-dimensional (3D) ceMRA] in abdominal and iliac arteries versus the reference standard intra-arterial digital subtraction angiography (i.a.DSA) when indicating a therapy. Patients suspected of having abdominal or iliac artery stenosis were included in this study. A positive vote of the local Ethics Committee was given. After written informed consent was obtained, 37 patients were enrolled, of which 34 were available for image evaluation. Both 3D ceMRA and i.a. DSA were performed for each patient. The dosage for 3D ceMRA was 0.1 mmol/kg body weight in a 1.5-T scanner with a phased-array coil. The parameters of the 3D-FLASH sequence were as follows: TR/TE 4.6/1.8 ms, effective thickness 3.5 mm, matrix 512 x 200, flip angle 30{sup o}, field of view 420 mm, TA 23 s, coronal scan orientation. Totally, 476 vessel segments were evaluated for stenosis degree by two radiologists in a consensus fashion in a blinded read. For each patient, a therapy was proposed, if clinically indicated. Sensitivity, specificity, positive and negative predictive values, and accuracy for stenoses {>=}50% were 68%, 92%, 44%, 97%, and 90%, respectively. In 13/34 patients, a discrepancy was found concerning therapy decisions based on MRA findings versus therapy decisions based on the reference standard DSA. The results showed that the used MRA imaging technique of abdominal and iliac arteries is not competitive to i.a. DSA, with a high rate of misinterpretation of the MRAs resulting in incorrect therapies.

Schaefer, Philipp J., E-mail: jp.schaefer@rad.uni-kiel.de; Schaefer, Fritz K. W.; Mueller-Huelsbeck, Stefan; Both, Markus; Heller, Martin; Jahnke, Thomas [University Hospital Schleswig-Holstein Campus Kiel, Department of Diagnostic Radiology (Germany)

2007-06-15

153

In Vivo Replication of Recombinant Murine Cytomegalovirus Driven by the Paralogous Major Immediate-Early Promoter Enhancer of Human Cytomegalovirus  

Microsoft Academic Search

Transcription of the major immediate-early (MIE) genes of cytomegaloviruses (CMV) is driven by a strong promoter-enhancer (MIEPE) complex. Transactivator proteins encoded by these MIE genes are essential for productive infection. Accordingly, the MIEPE is a crucial control point, and its regulation by activators and repressors is pertinent to virus replication. Since the MIEPE contains multiple regulatory elements, it was reasonable

NATASCHA K. A. GRZIMEK; JURGEN PODLECH; HANS-PETER STEFFENS; RAFAELA HOLTAPPELS; SUSANNE SCHMALZ; MATTHIAS J. REDDEHASE

1999-01-01

154

Development of a severe model of early coronary artery ligation-induced dysrhythmias in the anaesthetized rat.  

PubMed Central

1. The potential use of catecholamines to increase the severity of dysrhythmias evoked by coronary artery ligation in the anaesthetized rat was investigated. Drugs were given intravenously prior to ligation. 2 Pressor doses of adrenaline (5 microgram/kg) noradrenaline (1 microgram/kg) phenylephrine (5-10 microgram/kg), and angiotensin (0.25 microgram/kg) conferred protection against the development of dysrhythmias. 3 Atropine (1 mg/kg) increased mortality from ventricular fibrilloflutter (VF) and abolished the protective effects of phenylephrine (10 micrograms/kg). 4 Administration of isoprenaline (10 microgram/kg) significantly increased the incidence of and the mortality from VF. 5 The order of antidysrhythmic drug potency of Org 6001 (1-10 mg/kg), disopyramide (2-10 mg/kg) and practolol (2-10 mg/kg) was similar in both the standard (without isoprenaline) and modified (with isoprenaline) models. 6 Use of the modified method for antidysrhythmic screening purpose allows demonstration of statistically meaningful results with the use of relatively few animals. 7 Comparison of the pattern of VF in the rat heart induced by various means suggests that the diagnosis of ventricular fibrillation can be made with more confidence in the modified method compared to the standard method. PMID:7272592

Marshall, R. J.; Muir, A. W.; Winslow, E.

1981-01-01

155

Helper-dependent adenoviral vector achieves prolonged, stable expression of interleukin-10 in rabbit carotid arteries but does not limit early atherogenesis.  

PubMed

Vascular gene therapy could potentially complement or replace current therapies for human atherosclerosis, while avoiding their side effects. However, development of vascular gene therapy is limited by lack of a useful vector. Helper-dependent adenovirus (HDAd) shows promise to overcome this barrier because, unlike first-generation adenovirus, HDAd achieves durable transgene expression in the artery wall with minimal inflammation. To begin to test whether HDAd, delivered to the artery wall, can limit atherosclerosis we constructed HDAd that expresses rabbit interleukin (IL)-10, a potent atheroprotective cytokine, and tested its activity in a rabbit model of early carotid atherogenesis. HDAd expressed immunoreactive, active IL-10 in vitro. In contrast to other HDAd-expressed transgenes, IL-10 expression from HDAd increased significantly between 3 days and 2 weeks after infusion and remained stable for at least 8 weeks. Rising, persistent IL-10 expression was associated with relative persistence of HDAdIL-10 genomes 4 weeks after infusion, compared with HDAdNull genomes. Surprisingly, IL-10 expression had no significant effects on atherosclerotic lesion size, macrophage content, or expression of either adhesion molecules or atherogenic cytokines. These results might be due to inadequate protein expression in vivo or lack of suitability of this rabbit model to reveal IL-10 therapeutic effects. IL-10 remains a promising agent for vascular gene therapy and HDAd remains a promising vector; however, proof of efficacy of HDAdIL-10 is elusive. Future preclinical studies will be aimed at increasing IL-10 expression levels and improving the sensitivity of this animal model to detect atheroprotective effects. PMID:21198399

Du, Liang; Dronadula, Nagadhara; Tanaka, Shinji; Dichek, David A

2011-08-01

156

Helper-Dependent Adenoviral Vector Achieves Prolonged, Stable Expression of Interleukin-10 in Rabbit Carotid Arteries but Does Not Limit Early Atherogenesis  

PubMed Central

Abstract Vascular gene therapy could potentially complement or replace current therapies for human atherosclerosis, while avoiding their side effects. However, development of vascular gene therapy is limited by lack of a useful vector. Helper-dependent adenovirus (HDAd) shows promise to overcome this barrier because, unlike first-generation adenovirus, HDAd achieves durable transgene expression in the artery wall with minimal inflammation. To begin to test whether HDAd, delivered to the artery wall, can limit atherosclerosis we constructed HDAd that expresses rabbit interleukin (IL)-10, a potent atheroprotective cytokine, and tested its activity in a rabbit model of early carotid atherogenesis. HDAd expressed immunoreactive, active IL-10 in vitro. In contrast to other HDAd-expressed transgenes, IL-10 expression from HDAd increased significantly between 3 days and 2 weeks after infusion and remained stable for at least 8 weeks. Rising, persistent IL-10 expression was associated with relative persistence of HDAdIL-10 genomes 4 weeks after infusion, compared with HDAdNull genomes. Surprisingly, IL-10 expression had no significant effects on atherosclerotic lesion size, macrophage content, or expression of either adhesion molecules or atherogenic cytokines. These results might be due to inadequate protein expression in vivo or lack of suitability of this rabbit model to reveal IL-10 therapeutic effects. IL-10 remains a promising agent for vascular gene therapy and HDAd remains a promising vector; however, proof of efficacy of HDAdIL-10 is elusive. Future preclinical studies will be aimed at increasing IL-10 expression levels and improving the sensitivity of this animal model to detect atheroprotective effects. PMID:21198399

Du, Liang; Dronadula, Nagadhara; Tanaka, Shinji

2011-01-01

157

Enhanced normalisation of CD4/CD8 ratio with early antiretroviral therapy in primary HIV infection  

PubMed Central

Introduction Despite normalization of total CD4 counts, ongoing immune dysfunction is noted amongst those on antiretroviral therapy (ART). Low CD4/CD8 ratio is associated with a high risk of AIDS and non-AIDS events and may act as a marker of immune senescence [1]. This ratio is improved by ART although normalization is uncommon (~7%) [2]. The probability of normalization of CD4 count is improved with immediate ART initiation in primary HIV infection (PHI) [3]. We examined whether CD4/CD8 ratio similarly normalized in immediate vs. deferred ART at PHI. Material and Methods Using data from the SPARTAC trial and the UK Register of HIV Seroconverters, we examined the effect of ART with time (continuous) from HIV seroconversion (SC) on CD4/CD8 ratio (?1) adjusted for sex, risk group, ethnicity, enrolment from an African site and both CD4 count and age at ART initiation. We also examined that effect by dichotomizing HIV duration at ART initiation (ART started within six months of SC: early ART; ART initiated>six months after SC: deferred). We also considered time to CD4 count normalization (?900 cells/mm3). Results In total, 353 initiated ART with median (IQR) 97.9 (60.5, 384.5) days from estimated seroconversion; 253/353 early ART, 100 deferred ART. At one year after starting ART, 114/253 (45%) early ART had normalized CD4/8 ratio, compared with 11/99 (11%) in the deferred group, whilst 83/253 (33%) of early ART had normalized CD4 counts, compared with 3/99 (3%) in the deferred group. Individuals initiating within six months of PHI were significantly more likely to reach normal ratio than those initiating later (HR, 95% CI 2.96, 1.75 – 5.01, p<0.001). The longer after SC ART was initiated, the reduced likelihood of achieving normalization of CD4/CD8 ratio (HR 0.98, 95% CI 0.96 – 0.99 for each 30-day increase). CD4 count at ART initiation was also associated with normalization, as expected (HR 1.002, 95% CI 1.001 – 1.002, p<0.001). There was an association between normal CD4/CD8 ratio and being virally suppressed (<400 copies HIV RNA/ml) p<0.001. CD4 count normalization was also significantly more likely for those initiating early (HR 5.00, 95% CI 1.52 – 16.41, p=0.008). Conclusions The likelihood of achieving normalization of CD4/CD8 ratios was increased if ART was initiated within six months of PHI. Higher CD4/CD8 ratio may reflect a more “normal” immune phenotype conferring enhanced prognosis and predict post-treatment control. PMID:25393989

Thornhill, John; Inshaw, Jamie; Oomeer, Soonita; Kaleebu, Pontiano; Cooper, David; Ramjee, Gita; Schechter, Mauro; Tambussi, Giuseppe; Fox, Julie; Maria Miro, Jose; Weber, Jonathan; Babiker, Abdel; Porter, Kholoud; Fidler, Sarah

2014-01-01

158

Early age strength enhancement of blended cement systems by CaCl{sub 2} and diethanol-isopropanolamine  

SciTech Connect

The enhancement of the 1 day strength of cementitious systems by a combination of calcium chloride (CaCl{sub 2}) and diethanol-isopropanolamine (DEIPA) was studied, particularly in blended cement systems. A combination of quantitative X-ray diffraction with Rietveld refinement (QXRD), scanning electron microscopy (SEM)/backscattered electron image analysis, thermogravimetric analysis (TGA), and isothermal calorimetry were used to investigate the mechanism of strength enhancement by the additives. The additives were found to increase the early age mortar strength by enhancing the cement hydration, with the DEIPA enhancing primarily the aluminate hydration. DEIPA also affected the morphology of portlandite which was formed as thin plates. In parallel, the calcium-to-silica ratio of the C-S-H was found to increase with the use of DEIPA, possibly because of the inclusion of microcrystalline portlandite. After 48 h DEIPA was found to directly enhance the rate of reaction of granulated blast-furnace slag and fly ash.

Riding, Kyle, E-mail: kyleriding@yahoo.co [Department of Civil Engineering, Kansas State University, Manhattan, KS 66506 (United States); Silva, Denise A. [W.R. Grace and Co., Cambridge, Massachusetts 02140 (United States); Scrivener, Karen [Laboratory of Construction Materials, Ecole Polytechnique Federale de Lausanne, CH-1015 (Switzerland)

2010-06-15

159

Activation of Notch signaling by short-term treatment with Jagged-1 enhances store-operated Ca(2+) entry in human pulmonary arterial smooth muscle cells.  

PubMed

Notch signaling plays a critical role in controlling proliferation and differentiation of pulmonary arterial smooth muscle cells (PASMC). Upregulated Notch ligands and Notch3 receptors in PASMC have been reported to promote the development of pulmonary vascular remodeling in patients with pulmonary arterial hypertension (PAH) and in animals with experimental pulmonary hypertension. Activation of Notch receptors by their ligands leads to the cleavage of the Notch intracellular domain (NICD) to the cytosol by ?-secretase; NICD then translocates into the nucleus to regulate gene transcription. In this study, we examined whether short-term activation of Notch functionally regulates store-operated Ca(2+) entry (SOCE) in human PASMC. Treatment of PASMC with the active fragment of human Jagged-1 protein (Jag-1) for 15-60 min significantly increased the amplitude of SOCE induced by passive deletion of Ca(2+) from the intracellular stores, the sarcoplasmic reticulum (SR). The Jag-1-induced enhancement of SOCE was time dependent: the amplitude was maximized at 30 min of treatment with Jag-1, which was closely correlated with the time course of Jag-1-mediated increase in NICD protein level. The scrambled peptide of Jag-1 active fragment had no effect on SOCE. Inhibition of ?-secretase by N-[N-(3,5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester (DAPT) significantly attenuated the Jag-1-induced augmentation of SOCE. In addition to the short-term effect, prolonged treatment of PASMC with Jag-1 for 48 h also markedly enhanced the amplitude of SOCE. These data demonstrate that short-term activation of Notch signaling enhances SOCE in PASMC; the NICD-mediated functional interaction with store-operated Ca(2+) channels (SOC) may be involved in the Jag-1-mediated enhancement of SOCE in human PASMC. PMID:24573085

Yamamura, Hisao; Yamamura, Aya; Ko, Eun A; Pohl, Nicole M; Smith, Kimberly A; Zeifman, Amy; Powell, Frank L; Thistlethwaite, Patricia A; Yuan, Jason X-J

2014-05-01

160

Early treatment response to sorafenib for rabbit VX2 orthotic liver tumors: evaluation by quantitative contrast-enhanced ultrasound.  

PubMed

The aim of our study was to investigate the application of contrast-enhanced ultrasound (CEUS) and its quantification analysis for the prediction of early treatment response of sorafenib on rabbit VX2 liver tumor model. Rabbits were implanted VX2 tumor mass to establish a liver tumor model. Fourteen days after tumor implantation, rabbits presented with single liver tumor were randomly divided into two groups. Rabbits in treatment group were given by gavage once a day for 14 days with sorafenib suspension at a dose of 30 mg/kg, whereas rabbits in control group were given saline by gavage of the same volume. CEUS was performed before treatment and 3, 7, 14 days after treatment for the analysis of tumor size, enhancement pattern, and necrosis range. The time intensity curve (TIC) was used to obtain quantitative parameters of enhancement patterns. Before sorafenib administration, tumor volumes ranged from 0.24 to 0.75 cm(3) (mean 0.49?±?0.18 cm(3)) in treatment group and 0.24 to 0.44 cm(3) (mean 0.30?±?0.12 cm(3)) in control group. The dynamic enhancement patterns of tumors were homogeneous hyper-enhancement (n?=?8), heterogeneous hyper-enhancement (n?=?4), and peripheral rim-like enhancement (n?=?2). All tumors of the treatment group presented with peripheral rim-like enhancement with large necrotic area after sorafenib administration, whereas tumors of the control group showed heterogeneous hyper-enhancement (n?=?5) and peripheral rim-like enhancement (n?=?2). There was a significant difference in area under the curve (AUC) before and after sorafenib treatment (P?=?0.045). CEUS may be of value in the evaluation of early therapeutic response after sorafenib administration. PMID:25448880

Kong, Wen-Tao; Yuan, Hai-Xia; Cai, Hao; Wang, Wen-Ping; Tang, Yang; Zhang, Xiao-Long

2014-12-01

161

Numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system  

USGS Publications Warehouse

In this paper, two numerical models are presented to simulate an enhanced very early time electromagnetic (VETEM) prototype system, which is used for buried-object detection and environmental problems. Usually, the VETEM system contains a transmitting loop antenna and a receiving loop antenna, which run on a lossy ground to detect buried objects. In the first numerical model, the loop antennas are accurately analyzed using the Method of Moments (MoM) for wire antennas above or buried in lossy ground. Then, Conjugate Gradient (CG) methods, with the use of the fast Fourier transform (FFT) or MoM, are applied to investigate the scattering from buried objects. Reflected and scattered magnetic fields are evaluated at the receiving loop to calculate the output electric current. However, the working frequency for the VETEM system is usually low and, hence, two magnetic dipoles are used to replace the transmitter and receiver in the second numerical model. Comparing these two models, the second one is simple, but only valid for low frequency or small loops, while the first modeling is more general. In this paper, all computations are performed in the frequency domain, and the FFT is used to obtain the time-domain responses. Numerical examples show that simulation results from these two models fit very well when the frequency ranges from 10 kHz to 10 MHz, and both results are close to the measured data.

Cui, T.J.; Chew, W.C.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.; Abraham, J.D.

2000-01-01

162

A Case Study of the Use of Internet Photobook Technology to Enhance Early Childhood "Scientist" Identity  

NASA Astrophysics Data System (ADS)

There are many influences on a child's identity. Photobook technology purposefully prepared around science explorations presents a modern opportunity to repeatedly trigger memories that reinforce the "me, as scientist" viewpoint. Semi-structured interviews at 6 and 8 years of age were conducted with a child who was the subject of a photobook of everyday science activities to gain insights into his thinking about the nature of science and how he interprets his younger self participating. Interview data were recorded, transcribed and analyzed using dimensions from the previously established parameters for the nature of science. The child's statements about his participation in the photos were matched to these dimensions to consider how he sees himself "doing science" through his early years. Preliminary findings suggest that the child recognizes elements of science and regards himself as an active participant. In both interviews, the child reinforces these views by the opportunity to revisit the experiences in the photobook. Affective components may motivate further science involvement as well: the child enjoyed the time and attention that the photos and discussion provided; the child took pride in being the subject of a book. This case study suggests that there is a fertile field of research to investigate how, for whom, and in what ways internet photobook technology may enhance a child's developing identity as capable science explorer.

Katz, Phyllis

2011-10-01

163

Detection of buried targets using a new enhanced very early time electromagnetic (VETEM) prototype system  

USGS Publications Warehouse

In this paper, numerical simulations of a new enhanced very early time electromagnetic (VETEM) prototype system are presented, where a horizontal transmitting loop and two horizontal receiving loops are used to detect buried targets, in which three loops share the same axis and the transmitter is located at the center of receivers. In the new VETEM system, the difference of signals from two receivers is taken to eliminate strong direct-signals from the transmitter and background clutter and furthermore to obtain a better SNR for buried targets. Because strong coupling exists between the transmitter and receivers, accurate analysis of the three-loop antenna system is required, for which a loop-tree basis function method has been utilized to overcome the low-frequency breakdown problem. In the analysis of scattering problem from buried targets, a conjugate gradient (CG) method with fast Fourier transform (FFT) is applied to solve the electric field integral equation. However, the convergence of such CG-FFT algorithm is extremely slow at very low frequencies. In order to increase the convergence rate, a frequency-hopping approach has been used. Finally, the primary, coupling, reflected, and scattered magnetic fields are evaluated at receiving loops to calculate the output electric current. Numerous simulation results are given to interpret the new VETEM system. Comparing with other single-transmitter-receiver systems, the new VETEM has better SNR and ability to reduce the clutter.

Cui, T.J.; Chew, W.C.; Aydiner, A.A.; Wright, D.L.; Smith, D.V.

2001-01-01

164

Increased salt intake during early ontogenesis lead to development of arterial hypertension in salt-resistant Wistar rats.  

PubMed

Abstract A direct relationship exists between salt consumption and hypertension. Increased sodium intake does not automatically lead to a rise in blood pressure (BP) because of marked intra-individual variability in salt sensitivity. Wistar rats are a salt-resistant strain and increased salt intake in adults does not induce hypertension. Mechanisms regulating BP develop during early ontogenesis and increased sodium consumption by pregnant females leads to an increase in BP of their offspring, but early postnatal stages have not been sufficiently analyzed in salt-resistant strains of rats. The aim of this work was to study the effects of increased salt during early ontogeny on cardiovascular characteristics of Wistar rats. We used 16 control (C; 8 males + 8 females) rats fed with a standard diet (0.2% sodium) and 16 experimental (S; 8 males + 8 females) rats fed with a diet containing 0.8% sodium. BP was measured weekly and plasma renin activity, aldosterone and testosterone concentrations were assayed by radioimmunoassay after the experiment in 16-week-old animals. In the kidney, AT1 receptors were determined by the western blot. BP was higher in the S as compared with the C rats and did not differ between males and females. The relative left ventricle mass was increased in S as compared with C males and no differences were recorded in females. No significant differences between groups were found in hormonal parameters and AT1 receptors. Results indicate that moderately increased salt intake during postnatal ontogeny results in a BP rise even in salt-resistant rats. PMID:25050593

Svitok, Pavel; Molcan, Lubos; Vesela, Anna; Kruzliak, Peter; Moravcik, Roman; Zeman, Michal

2014-07-22

165

Early Career Boot Camp: a novel mechanism for enhancing early career development for psychologists in academic healthcare.  

PubMed

The purpose of this article is to describe a pilot mentoring program for Early Career Psychologists (ECPs) working in Academic Health Centers (AHCs) and synthesize the lessons learned to contribute to future ECP and AHC career development training programs. The authors describe an early career development model, named the Early Career Boot Camp. This intensive experience was conducted as a workshop meant to build a supportive network and to provide mentorship and survival tools for working in AHCs. Four major components were addressed: professional effectiveness, clinical supervision, strategic career planning, and academic research. Nineteen attendees who were currently less than 5 years post completion of doctoral graduate programs in psychology participated in the program. The majority of boot camp components were rated as good to excellent, with no component receiving below average ratings. Of the components offered within the boot camp, mentoring and research activities were rated the strongest, followed by educational activities, challenges in AHCS, and promotion and tenure. The article describes the purpose, development, implementation, and assessment of the program in detail in an effort to provide an established outline for future organizations to utilize when mentoring ECPs. PMID:22327238

Foran-Tuller, Kelly; Robiner, William N; Breland-Noble, Alfiee; Otey-Scott, Stacie; Wryobeck, John; King, Cheryl; Sanders, Kathryn

2012-03-01

166

A Single Dose of Antenatal Betamethasone Enhances Isoprenaline and Prostaglandin E2Induced Relaxation of Preterm Ovine Pulmonary Arteries  

Microsoft Academic Search

?-Adrenergic agonists and prostaglandin E2 (PGE2) play an important role in perinatal pulmonary circulation. We have determined the effect of antenatal glucocorticoid treatment on isoprenaline- and PGE2-mediated relaxation of pulmonary arteries of newborn preterm lambs. Ovine fetuses (121 days of gestation; term = 150 days) received a single intramuscular dose of betamethasone (0.5 mg\\/kg) or saline. Fifteen hours after the

Yuansheng Gao; Jean-Francois Tolsa; Hai Shen; J. Usha Raj

1998-01-01

167

Determination of time-course change rate for arterial xenon using the time course of tissue xenon concentration in xenon-enhanced computed tomography  

SciTech Connect

In calculating tissue blood flow (TBF) according to the Fick principle, time-course information on arterial tracer concentration is indispensable and has a considerable influence on the accuracy of calculated TBF. In TBF measurement by xenon-enhanced computed tomography (Xe-CT), nonradioactive xenon gas is administered by inhalation as a tracer, and end-tidal xenon is used as a substitute for arterial xenon. There has been the assumption that the time-course change rate for end-tidal xenon concentration (Ke) and that for arterial xenon concentration (Ka) are substantially equal. Respiratory gas sampling is noninvasive to the patient and Ke can be easily measured by exponential curve fitting to end-tidal xenon concentrations. However, it is pointed out that there would be a large difference between Ke and Ka in many cases. The purpose of this work was to develop a method of determining the Ka value using the time course of tissue xenon concentration in Xe-CT. The authors incorporated Ka into the Kety autoradiographic equation as a parameter to be solved, and developed a method of least-squares to obtain the solution for Ka from the time-course changes in xenon concentration in the tissue. The authors applied this method of least-squares to the data from Xe-CT abdominal studies performed on 17 patients; the solution for Ka was found pixel by pixel in the spleen, and its Ka map was created for each patient. On the one hand, the authors obtained the average value of the Ka map of the spleen as the calculated Ka (Ka{sub calc}) for each patient. On the other hand, the authors measured Ka (Ka{sub meas}) using the time-course changes in CT enhancement in the abdominal aorta for each patient. There was a good correlation between Ka{sub calc} and Ka{sub meas} (r=0.966, P<0.0001), and these two Ka values were close to each other (Ka{sub calc}=0.935xKa{sub meas}+0.089). This demonstrates that Ka{sub calc} would be close to the true Ka value. Accuracy of TBF by Xe-CT can be improved with use of the average value of the Ka map of an organ like the spleen that has a single blood supply (only arterial inflow)

Sase, Shigeru; Takahashi, Hideaki; Ikeda, Hiroki; Kobayashi, Minoru; Matsumoto, Nobuyuki; Suzuki, Michihiro [Anzai Medical Co., Ltd., 3-9-15 Nishi-Shinagawa, Shinagawa-ku, Tokyo 141-0033 (Japan); Department of Internal Medicine, Division of Gastroenterology and Hepatology, School of Medicine, St. Marianna University, 2-16-1 Miyamae-ku, Sugao, Kawasaki 216-5811 (Japan)

2008-06-15

168

78 FR 13294 - Enhanced Prudential Standards and Early Remediation Requirements for Foreign Banking...  

Federal Register 2010, 2011, 2012, 2013

...Early Remediation Requirements for Foreign Banking Organizations and Foreign Nonbank Financial...under section 166 of the Act for foreign banking organizations and foreign nonbank financial...Early Remediation Requirements for Foreign Banking Organizations and Foreign Nonbank...

2013-02-27

169

Music and Speech Listening Enhance the Recovery of Early Sensory Processing after Stroke  

Microsoft Academic Search

Our surrounding auditory environment has a dramatic influence on the development of basic auditory and cognitive skills, but little is known about how it influences the recovery of these skills after neural damage. Here, we studied the long-term effects of daily music and speech listening on auditory sensory memory after middle cerebral artery (MCA) stroke. In the acute recovery phase,

Teppo Särkämö; Elina Pihko; Sari Laitinen; Anita Forsblom; Seppo Soinila; Mikko Mikkonen; Taina Autti; Heli M. Silvennoinen; Jaakko Erkkilä; Matti Laine; Isabelle Peretz; Marja Hietanen; Mari Tervaniemi

2010-01-01

170

Chronic hypoxia-induced upregulation of Ca2+-activated Cl? channel in pulmonary arterial myocytes: a mechanism contributing to enhanced vasoreactivity  

PubMed Central

Chronic hypoxic pulmonary hypertension (CHPH) is associated with altered expression and function of cation channels in pulmonary arterial smooth muscle cells (PASMCs), but little is known for anion channels. The Ca2+-activated Cl? channel (CaCC), recently identified as TMEM16A, plays important roles in pulmonary vascular function. The present study sought to determine the effects of chronic hypoxia (CH) on the expression and function of CaCCs in PASMCs, and their contributions to the vascular hyperreactivity in CHPH. Male Wistar rats were exposed to room air or 10% O2 for 3–4 weeks to generate CHPH. CaCC current (ICl.Ca) elicited by caffeine-induced Ca2+ release or by depolarization at a constant high [Ca2+]i (500 or 750 nm) was significantly larger in PASMCs of CH rats compared to controls. The enhanced ICl.Ca density in CH PASMCs was unrelated to changes in amplitude of Ca2+ release, Ca2+-dependent activation, voltage-dependent properties or calcineurin-dependent modulation of CaCCs, but was associated with increased TMEM16A mRNA and protein expression. Maximal contraction induced by serotonin, an important mediator of CHPH, was potentiated in endothelium-denuded pulmonary arteries of CH rats. The enhanced contractile response was prevented by the CaCC blockers niflumic acid and T16Ainh-A01, or by the L-type Ca2+ channel antagonist nifedipine. The effects of niflumic acid and nifedipine were non-additive. Our results demonstrate for the first time that CH increases ICl.Ca density, which is attributable to an upregulation of TMEM16A expression in PASMCs. The augmented CaCC activity in PASMCs may potentiate membrane depolarization and L-type channel activation in response to vasoconstrictors and enhance pulmonary vasoreactivity in CHPH. PMID:22674716

Sun, Hui; Xia, Yang; Paudel, Omkar; Yang, Xiao-Ru; Sham, James S K

2012-01-01

171

THE EFFECT OF HELIUM-ENHANCED STELLAR POPULATIONS ON THE ULTRAVIOLET-UPTURN PHENOMENON OF EARLY-TYPE GALAXIES  

SciTech Connect

Recent observations and modeling of globular clusters (GCs) with multiple populations strongly indicate the presence of super-helium-rich subpopulations in old stellar systems. Motivated by this, we have constructed new population synthesis models with and without helium-enhanced subpopulations to investigate their impact on the UV-upturn phenomenon of quiescent early-type galaxies (ETGs). We find that our models with helium-enhanced subpopulations can naturally reproduce the strong UV-upturns observed in giant elliptical galaxies assuming an age similar to that of old GCs in the Milky Way. The major source of far-UV (FUV) flux, in this model, is relatively metal-poor and helium-enhanced hot horizontal-branch stars and their progeny. The Burstein et al. relation of the FUV - V color with metallicity is also explained either by the variation of the fraction of helium-enhanced subpopulations or by the spread in mean age of stellar populations in ETGs.

Chung, Chul; Yoon, Suk-Jin; Lee, Young-Wook, E-mail: ywlee2@yonsei.ac.kr [Center for Galaxy Evolution Research and Department of Astronomy, Yonsei University, Seoul 120-749 (Korea, Republic of)

2011-10-20

172

Diagnosis of extent of early gastric cancer using flexible spectral imaging color enhancement.  

PubMed

The demarcation line between the cancerous lesion and the surrounding area could be easily recognized with flexible spectral imaging color enhancement (FICE) system compared with conventional white light images. The characteristic finding of depressed-type early gastric cancer (EGC) in most cases was revealed as reddish lesions distinct from the surrounding yellowish non-cancerous area without magnification. Conventional endoscopic images provide little information regarding depressed lesions located in the tangential line, but FICE produces higher color contrast of such cancers. Histological findings in depressed area with reddish color changes show a high density of glandular structure and an apparently irregular microvessel in intervening parts between crypts, resulting in the higher color contrast of FICE image between cancer and surrounding area. Some depressed cancers are shown as whitish lesion by conventional endoscopy. FICE also can produce higher color contrast between whitish cancerous lesions and surrounding atrophic mucosa. For nearly flat cancer, FICE can produce an irregular structural pattern of cancer distinct from that of the surrounding mucosa, leading to a clear demarcation. Most elevated-type EGCs are detected easily as yellowish lesions with clearly contrasting demarcation. In some cases, a partially reddish change is accompanied on the tumor surface similar to depressed type cancer. In addition, the FICE system is quite useful for the detection of minute gastric cancer, even without magnification. These new contrasting images with the FICE system may have the potential to increase the rate of detection of gastric cancers and screen for them more effectively as well as to determine the extent of EGC. PMID:22912909

Osawa, Hiroyuki; Yamamoto, Hironori; Miura, Yoshimasa; Yoshizawa, Mitsuyo; Sunada, Keijiro; Satoh, Kiichi; Sugano, Kentaro

2012-08-16

173

Lumen Segmentation and Motion Estimation in B-mode and Contrast-Enhanced Ultrasound Images of the Carotid Artery in Patients with Atherosclerotic Plaque.  

PubMed

In standard B-mode ultrasound (BMUS), segmentation of the lumen of atherosclerotic carotid arteries and studying the lumen geometry over time are difficult owing to irregular lumen shapes, noise, artifacts, and echolucent plaques. Contrast enhanced ultrasound (CEUS) improves lumen visualization, but lumen segmentation remains challenging owing to varying intensities, CEUS-specific artifacts and lack of tissue visualization. To overcome these challenges, we propose a novel method using simultaneously acquired BMUS&CEUS image sequences. Initially, the method estimates nonrigid motion (NME) from the image sequences, using intensity-based image registration. The motion-compensated image sequence is then averaged to obtain a single 'epitome' image with improved signal-to-noise ratio. The lumen is segmented from the epitome image through an intensity joint-histogram classification and a graph-based segmentation. NME was validated by comparing displacements with manual annotations in eleven carotids. The average root-mean-squareerror (RMSE) was 112 73 ?m. Segmentation results were validated against manual delineations in the epitome images of two different datasets, respectively containing eleven (RMSE 191 43 ?m) and ten (RMSE 351 176 ?m) carotids. From the deformation fields, we derived arterial distensibility with values comparable to the literature. The average errors in all experiments were in the inter-observer variability range. To the best of our knowledge, this is the first study exploiting combined BMUS&CEUS images for atherosclerotic carotid lumen segmentation. PMID:25423650

Dias Bispo Carvalho, Diego; Akkus, Zeynettin; van den Oord, Stijn; Schinkel, Arend; van der Steen, Ton; Niessen, Wiro; Bosch, Hans; Klein, Stefan

2014-11-21

174

Effects of Org 7797 on early, late and inducible arrhythmias following coronary artery occlusion in rats and dogs.  

PubMed Central

1. The class Ic steroidal antiarrhythmic agent, Org 7797, was compared with two other Ic agents, flecainide and propafenone for intravenous activity against ischaemia-related cardiac arrhythmias and for electrophysiological actions in vivo. In addition the haemodynamic effects of Org 7797 were assessed in greyhounds. 2. Org 7797 (0.5 mg kg-1) significantly reduced the expected incidence of early ischaemia-induced ventricular fibrillation (VF) in rats and greyhound dogs and at doses of 0.5-1.0 mg kg-1 antagonized reperfusion-induced arrhythmias. Comparative studies in rats showed Org 7797 to be 2-4 times more potent than flecainide or propafenone. 3. Org 7797 (0.5 mg kg-1) slowed intracardiac conduction in anaesthetized beagles and again was at least 2-4 times more potent than flecainide or propafenone. 4. Org 7797 (0.5 and 2.0 mg kg-1), flecainide (1.0 and 2.0 mg kg-1) or propafenone (0.5 and 2.0 mg kg-1), did not significantly prevent induction of tachyarrhythmias (VT) in dogs with 5-6 day old myocardial infarcts although all 3 drugs appeared to prevent induced VF. All 3 drugs (notably flecainide) did however reduce the VT rate. 5. All 3 drugs (1-2 mg kg-1) suppressed spontaneous tachyarrhythmias in conscious beagle dogs with 1-2 day old infarcts. Propafenone was the least effective. 6. In an antifibrillatory dose (0.5 mg kg-1), the major haemodynamic effect of Org 7797 was a 10% increase in peripheral vascular resistance. Stroke volume, cardiac output and coronary blood flow were unchanged. In therapeutic doses, Org 7797 was also less negatively chronotropic than flecainide.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1810599

Winslow, E.; Campbell, J. K.; Barron, E.; Marshall, R. J.; Muir, A. W.

1991-01-01

175

Early Re-Do Surgery for Glioblastoma Is a Feasible and Safe Strategy to Achieve Complete Resection of Enhancing Tumor  

PubMed Central

Background Complete resection of enhancing tumor as assessed by early (<72 hours) postoperative MRI is regarded as the optimal result in glioblastoma surgery. As yet, there is no consensus on standard procedure if post-operative imaging reveals unintended tumor remnants. Objective The current study evaluated the feasibility and safety of an early re-do surgery aimed at completing resections with the aid of 5-ALA fluorescence and neuronavigation after detection of enhancing tumor remnants on post-operative MRI. Methods From October 2008 to October 2012 a single center institutional protocol offered a second surgery within one week to patients with unintentional incomplete glioblastoma resection. We report on the feasibility of the use 5-ALA fluorescence guidance, the extent of resection (EOR) rates and complications of early re-do surgery. Results Nine of 151 patients (6%) with glioblastoma resections had an unintentional tumor remnant with a volume >0.175 cm3. 5-ALA guided re-do surgery completed the resection (CRET) in all patients without causing neurological deficits, infections or other complications. Patients who underwent a re-do surgery remained hospitalized between surgeries, resulting in a mean length of hospital stay of 11 days (range 7-15), compared to 9 days for single surgery (range 3-23; p=0.147). Conclusion Our early re-do protocol led to complete resection of all enhancing tumor in all cases without any new neurological deficits and thus provides a similar oncological result as intraoperative MRI (iMRI). The repeated use of 5-ALA induced fluorescence, used for identification of small remnants, remains highly sensitive and specific in the setting of re-do surgery. Early re-do surgery is a feasible and safe strategy to complete unintended subtotal resections. PMID:24348904

Schucht, Philippe; Murek, Michael; Jilch, Astrid; Seidel, Kathleen; Hewer, Ekkehard; Wiest, Roland; Raabe, Andreas; Beck, Jürgen

2013-01-01

176

Assessing the end-organ in peripheral arterial occlusive disease—from contrast—enhanced ultrasound to blood-oxygen-level-dependent MR imaging  

PubMed Central

Peripheral arterial occlusive disease (PAOD) is a result of atherosclerotic disease which is currently the leading cause of morbidity and mortality in the western world. Patients with PAOD may present with intermittent claudication or symptoms related to critical limb ischemia. PAOD is associated with increased mortality rates. Stenoses and occlusions are usually detected by macrovascular imaging, including ultrasound and cross-sectional methods. From a pathophysiological view these stenoses and occlusions are affecting the microperfusion in the functional end-organs, such as the skin and skeletal muscle. In the clinical arena new imaging technologies enable the evaluation of the microvasculature. Two technologies currently under investigation for this purpose on the end-organ level in PAOD patients are contrast-enhanced ultrasound (CEUS) and blood-oxygen-level-dependent (BOLD) MR imaging (MRI). The following article is providing an overview about these evolving techniques with a specific focus on skeletal muscle microvasculature imaging in PAOD patients. PMID:24834413

Partovi, Sasan; Jacobi, Bjoern; Fergus, Nathan; Schulte, Anja-Carina; Robbin, Mark R.; Bilecen, Deniz; Staub, Daniel

2014-01-01

177

Right Pulmonary Artery Distensibility Index (RPAD Index). A field study of an echocardiographic method to detect early development of pulmonary hypertension and its severity even in the absence of regurgitant jets for Doppler evaluation in heartworm-infected dogs.  

PubMed

Despite the term "heartworm disease" Dirofilaria immitis infection in dogs should be considered a pulmonary arterial disease that might only involve the right heart structures in its late stage. Chronic infection by adult heartworms in dogs results in proliferative endoarteritis leading to progressively increasing pulmonary artery pressure due to reduced elasticity. Elasticity allows the pulmonary arteries to stretch in response to each pulse and helps maintain a relatively constant pressure in the arteries despite the pulsating nature of the blood flow. Pulmonary artery distensibility for both acute and chronic pulmonary hypertension has been investigated in humans using MRI and has been correlated with the severity of hypertension and its outcome and treatment response. The aim of the present study was to investigate whether echocardiographic measurement of the percentage change in diameter of the right pulmonary artery in systole and diastole (distensibility) may be of value in assessing the presence and severity of pulmonary hypertension in heartworm-infected dogs. The Right Pulmonary Artery Distensibility Index (RPAD Index) (which is calculated as the difference in diameter of the right pulmonary artery in systole and diastole) was calculated in healthy and naturally infected heartworm-positive dogs. The right pulmonary artery was chosen because it is usually affected earlier and to a greater degree. Data were obtained from healthy heartworm-free dogs without any clinical, radiographic, or echocardiographic signs of pulmonary hypertension; naturally infected heartworm-positive dogs in different stages of the disease in which pulmonary pressure could be measured by Doppler echocardiography (using tricuspid and or pulmonary regurgitation velocity and pressure gradient); and naturally infected heartworm-positive dogs in different stages of the disease (with or without tricuspid and or pulmonary regurgitation) in which the pulmonary pressure was measured invasively and noninvasively if possible. Results of these evaluations indicated that RPAD Index is a valuable method for early detection of the presence and severity of pulmonary hypertension in heartworm-infected dogs even in the absence of regurgitant jets for Doppler evaluation and that there is a strong correlation between the RPAD Index and the level of pulmonary hypertension. PMID:25218885

Venco, Luigi; Mihaylova, Liliya; Boon, June A

2014-11-15

178

Enhancing the Early Childhood Development System in Yakutia (Russia): Meeting the Challenges  

ERIC Educational Resources Information Center

The Yakutia Republic is currently working to update its early childhood development (ECD) system. Its goal is to ensure a high quality environment for early learning and child care and to enable higher enrolment levels. Currently, a high priority for the Government of Yakutia is to increase access to pre-school education, given the significant…

Kotnik, Jure; Shmis, Tigran

2011-01-01

179

Improving Early Adaptation Following Long Duration Spaceflight by Enhancing Vestibular Information  

NASA Technical Reports Server (NTRS)

Crewmember adapted to the microgravity state may need to egress the vehicle within a few minutes for safety and operational reasons after g-transitions. The transition from one sensorimotor state to another consists of two main mechanisms: strategic and plastic-adaptive and have been demonstrated in astronauts returning after long duration space flight. Strategic modifications represent "early adaptation" -immediate and transitory changes in control that are employed to deal with short-term changes in the environment. If these modifications are prolonged then plastic-adaptive changes are evoked that modify central nervous system function, automating new behavioral responses. More importantly, this longer term adaptive recovery mechanism was significantly associated with their strategic ability to recover on the first day after return to Earth G. We are developing a method based on stochastic resonance (SR) to enhance information transfer by improving the brain's ability to detect vestibular signals especially when combined with balance training exercises for rapid improvement in functional skill, for standing and mobility. The countermeasure to improve post-flight balance and locomotor disturbances is a stimulus delivery system that is wearable/portable providing low imperceptible levels of white noise based binaural bipolar electrical stimulation of the vestibular system (stochastic vestibular stimulation, SVS). The techniques for improving signal detection using SVS may thus provide additional information to improve such strategic abilities and thus help in significantly reducing the number of days required to recover functional performance to preflight levels after long duration space flight. We have conducted a series of studies to document the efficacy of SVS stimulation on balance/locomotion tasks on unstable surfaces and motion tracking tasks during intra-vestibular system conflicts. In an initial study, we showed that SVS improved overall balance performance while standing on an unstable surface indicating that SVS may be sufficient to provide a comprehensive countermeasure approach for improving postural stability. In a second study, we showed that SVS improved locomotor performance on a treadmill mounted on an oscillating platform indicating that SVS may also be used to maximize locomotor performance during walking in unstable environments. In a third study, SVS was evaluated during an otolith-canal conflict scenario in a variable radius centrifuge at low frequency of oscillation (0.1 Hz) on both eye movements and perceptual responses (using a joystick) to track imposed oscillations. The variable radius centrifuge provides a selective tilting sensation that is detectable only by the otolith organs providing conflicting information from the canal organs of the vestibular system (intra-vestibular conflict). Results show that SVS significantly reduced the timing difference between both the eye movement responses as well as the perceptual tracking responses with respect to the imposed tilt sensations. These results indicate that SVS can improve performance in sensory conflict scenarios like that experienced during space flight. Such a SR countermeasure will act synergistically along with the pre-and in-flight adaptability training protocols providing an integrated, multi-disciplinary countermeasure capable of fulfilling multiple requirements making it a comprehensive and cost effective countermeasure approach to enhance sensorimotor capabilities following long-duration space flight.

Mulavara, Ajitkumar; Kofman, Igor; DeDios, Yiri E.; Galvan, Raquel; Miller, Chris; Peters, Brian; Cohen, Helen; Jeevarajan, Jerome; Reschke, Millard; Wood, Scott; Bloomberg, Jacob

2014-01-01

180

Enhancing Drought Early Warning System for Sustainable Water Resources and Agricultural Management through Apllication of Space Science - Nigeria in Perspective  

NASA Astrophysics Data System (ADS)

Enhancing Drought Early Warning System for Sustainable Water Resources and Agriculture Management through Application of Space Science - Nigeria in Perspective BY J N Okpara L E Akeh Anuforom P B Aribo and S O Olayanju Directorate of Applied Meteorological Services Nigerian Meteorological Agency NIMET P M B 615 Garki Abuja Nigeria e-mail underline Juddy Okpara yahoo co uk and underline tonycanuforom yahoo com underline Abstract This paper attempts to highlight the importance of drought early warning system in water resources and agricultural management in Nigeria Various studies have shown that the negative impacts of droughts and other forms of extreme weather phenomena can be substantially reduced by providing early warning on any impending weather extremes X-rayed in this study are the various techniques presently used by the Nigerian Meteorological Agency NIMET in generating information for meteorological Early Warning System EWS which are based on models that make use of ground-based raingauge data and sea surface temperatures SST Komuscu standardized precipitation index SPI inclusive These methods are often limited by such factors as network density of stations limited communication infrastructure human inefficiency etc NIMET is therefore embarking on the development of a new Satellite Agrometeorological Information System SAMIS-Nigeria for famine and drought early warning The system combines satellite data with raingauge data to give a range of

Okpara, J. N.; Akeh, L. E.; Anuforom, A. C.; Aribo, P. B.; Olayanju, S. O.

181

Decreased flow-mediated dilatation with increased arterial stiffness and thickness as early signs of atherosclerosis in polymyositis and dermatomyositis patients.  

PubMed

Several autoimmune rheumatic diseases have been associated with accelerated atherosclerosis or other different types of vasculopathy depending on the underlying disease, leading to increased cardio- and cerebrovascular disease risk. Polymyositis (PM) and dermatomyositis (DM), members of idiopathic inflammatory myopathies (IIMs), a group of systemic autoimmune diseases are also associated with elevated risk of cardiovascular diseases (CVD). Up until now, no specific data is known on the mechanisms, risk factors, or possible vasculopathy leading to increased CVD risk. The aims of the present study were to assess the flow-mediated dilatation of the brachial artery by a TensioClinic arteriograph and to measure the thickness of carotid artery intima-media, the augmentation index, and the pulse wave velocity using high-resolution ultrasonography in a cohort of PM and DM patients. We also investigated the correlation of these parameters with the traditional risk factors of atherosclerosis and overall cardiovascular status within PM and DM patients. Twenty-seven patients (21 females, six males) with IIMs were enrolled in this study, and 38 healthy individuals matched for sex and age served as controls. We found a decreased flow-mediated dilatation in the brachial artery (6.36 vs. 8.39 %) with increased arterial stiffness and carotid artery thickness in our patients compared to healthy controls. We found significantly decreased flow-mediated dilatation of the brachial artery (5.57 vs. 8.39 %) in DM patients. We also detected a correlation between these parameters and the traditional cardiovascular risk factors, as well as hypertriglyceridemy, hypertension, and peripheral arterial disease. In DM, overall, more vascular abnormalities were found than in PM. Our findings suggest that flow-mediated dilatation of the brachial artery, arterial stiffness, and carotid artery thickness measurements could be beneficial for predicting the CVD risk in myositis patients. Further investigations need to find the potential differences and role of inflammation and immune mechanisms in atherosclerotic processes in DM and PM. PMID:24615538

Vincze, Melinda; Dér, H; Kerekes, Gy; Szodoray, P; Zeher, M; Dankó, K; Soltész, P

2014-11-01

182

Early methylphenidate exposure enhances cocaine self-administration but not cocaine-induced conditioned place preference in young adult rats  

PubMed Central

Rationale Previous studies in rodents show that early exposure to methylphenidate alters later responsiveness to drugs of abuse. An interesting feature of these studies is that early methylphenidate treatment decreases the rewarding value of cocaine when measured by conditioned place preference (CPP), but the same treatment increases cocaine self-administration. Objective The goal of the present study was to examine the effects of early methylphenidate exposure on cocaine-induced responding using both reward paradigms. Methods Rats were treated with methylphenidate (0, 2, or 5 mg/kg) from postnatal day (PD) 11 to PD 20 and then cocaine-induced CPP or cocaine self-administration was measured in separate groups of rats in adulthood. The CPP procedure included eight days of acquisition training, eight days of extinction training, and a reinstatement test. Rats were conditioned with 0, 10 or 20 mg/kg cocaine. Reinstatement was assessed after a priming dose of cocaine (10 mg/kg). For the self-administration experiment, a jugular catheter was implanted and rats were trained to press a lever reinforced with cocaine (0.25 or 0.75 mg/kg/infusion) on a fixed ratio (FR) 1 schedule. Rats were gradually moved from an FR1 to an FR10 schedule and, after criterion was reached, rats were placed on a progressive ratio schedule for five days. Results Cocaine produced robust rewarding effects as determined by both the CPP and self-administration experiments; however, early methylphenidate exposure only enhanced the reinforcing effects of cocaine on the self-administration paradigm. Interestingly, this methylphenidate enhancement was only seen in male rats. Conclusions These data suggest that in males methylphenidate enhances the reinforcing value of cocaine, but not cocaine-associated cues. PMID:20848087

Crawford, Cynthia A.; Baella, Shelley A.; Farley, Cristal M.; Herbert, Matthew S.; Horn, Leslie R.; Campbell, Rachel H.; Zavala, Arturo R.

2010-01-01

183

Arterial insufficiency  

MedlinePLUS

... is hard for blood to flow through your arteries. Blood flow may be suddenly stopped due to a ... may have a stroke . If it affects the arteries that bring blood to your legs, you may have frequent leg ...

184

Improved early stroke detection: Wavelet-based perception enhancement of computerized tomography exams  

Microsoft Academic Search

Nonenhanced computerized tomography (CT) exams were used to detect acute stroke by notification of hypodense area. Infarction perception improvement by data denoising and local contrast enhancement in multi-scale domain was proposed. The wavelet-based image processing method enhanced the subtlest signs of hypodensity, which were often invisible in standard CT scan review. Thus improved detection efficiency of perceptual ischemic changes was

A. Przelaskowski; K. Sklinda; P. Bargie?; J. Walecki; M. Biesiadko-Matuszewska; M. Kazubek

2007-01-01

185

Arterialization, coronariogenesis and arteriogenesis  

Microsoft Academic Search

During embryonic life, the early vascular system consists of a network of immature endothelial channels called the primary plexus, which irrigates the growing embryo. Conducting vessels (arteries and veins) develop later, following the metabolic demand of the organ primordia. Embryologists described the development of conducting vessels as a process of investment of the primary plexus with undifferentiated mesenchymal cells, which

Borja Fernández

186

Enhancement by exogenous and locally generated angiotensin II of purinergic neurotransmission via angiotensin type 1 receptor in the guinea-pig isolated mesenteric artery  

PubMed Central

Angiotensin II is known to enhance sympathetic neurotransmission in the vasculature by increasing the release of noradrenaline, but little is known about the effect on the co-released transmitter, adenosine 5?-triphosphate (ATP). In the present study we have examined the effect of angiotensin II on the excitatory junction potential (e.j.p.) elicited by repetitive field stimulation in the guinea-pig isolated mesenteric artery, to establish the angiotensin II receptor subtype involved in modulating the release of ATP and the role of the endothelium in converting angiotensin I to angiotensin II. Suramin (300??M), a P2 purinoceptor antagonist, abolished both the e.j.ps and depolarizing response to ?,?-methylene-ATP, a stable analogue of ATP, without affecting the resting membrane potential and noradrenaline-induced depolarization. Angiotensin II (0.1??M) affected neither the resting membrane potential nor the amplitude of the first e.j.p., but increased the amplitudes of the subsequent e.j.ps. This enhancing effect of angiotensin II was abolished by CV-11974 (0.1??M), an angiotensin II type 1 (AT1) receptor antagonist, but unaffected by PD?123319 (1??M), an angiotensin II type 2 (AT2) receptor antagonist, or CGP?42112A (1??M), AT2 receptor ligand. Angiotensin I (0.1??M) exerted a similar effect on e.j.ps to that of angiotensin II. CV-11974 (0.1??M) or temocaprilat (10??M), an angiotensin converting enzyme (ACE) inhibitor, abolished the effect of angiotensin I. Removal of the endothelium did not alter the action of angiotensin I. The results of the present study indicate that the release of ATP from sympathetic nerves innervating the guinea-pig isolated mesenteric artery, as determined from the magnitude of the e.j.p., can be enhanced by angiotensin II via activation of prejunctional AT1 receptors. Qualitatively similar effects were observed with angiotensin I, which appears to be converted into angiotensin II by a subendothelial process. PMID:9384513

Onaka, Uran; Fujii, Koji; Abe, Isao; Fujishima, Masatoshi

1997-01-01

187

Musicians' enhanced neural differentiation of speech sounds arises early in life: developmental evidence from ages 3 to 30.  

PubMed

The perception and neural representation of acoustically similar speech sounds underlie language development. Music training hones the perception of minute acoustic differences that distinguish sounds; this training may generalize to speech processing given that adult musicians have enhanced neural differentiation of similar speech syllables compared with nonmusicians. Here, we asked whether this neural advantage in musicians is present early in life by assessing musically trained and untrained children as young as age 3. We assessed auditory brainstem responses to the speech syllables /ba/ and /ga/ as well as auditory and visual cognitive abilities in musicians and nonmusicians across 3 developmental time-points: preschoolers, school-aged children, and adults. Cross-phase analyses objectively measured the degree to which subcortical responses differed to these speech syllables in musicians and nonmusicians for each age group. Results reveal that musicians exhibit enhanced neural differentiation of stop consonants early in life and with as little as a few years of training. Furthermore, the extent of subcortical stop consonant distinction correlates with auditory-specific cognitive abilities (i.e., auditory working memory and attention). Results are interpreted according to a corticofugal framework for auditory learning in which subcortical processing enhancements are engendered by strengthened cognitive control over auditory function in musicians. PMID:23599166

Strait, Dana L; O'Connell, Samantha; Parbery-Clark, Alexandra; Kraus, Nina

2014-09-01

188

The enhancer landscape during early neocortical development reveals patterns of dense regulation and co-option.  

PubMed

Genetic studies have identified a core set of transcription factors and target genes that control the development of the neocortex, the region of the human brain responsible for higher cognition. The specific regulatory interactions between these factors, many key upstream and downstream genes, and the enhancers that mediate all these interactions remain mostly uncharacterized. We perform p300 ChIP-seq to identify over 6,600 candidate enhancers active in the dorsal cerebral wall of embryonic day 14.5 (E14.5) mice. Over 95% of the peaks we measure are conserved to human. Eight of ten (80%) candidates tested using mouse transgenesis drive activity in restricted laminar patterns within the neocortex. GREAT based computational analysis reveals highly significant correlation with genes expressed at E14.5 in key areas for neocortex development, and allows the grouping of enhancers by known biological functions and pathways for further studies. We find that multiple genes are flanked by dozens of candidate enhancers each, including well-known key neocortical genes as well as suspected and novel genes. Nearly a quarter of our candidate enhancers are conserved well beyond mammals. Human and zebrafish regions orthologous to our candidate enhancers are shown to most often function in other aspects of central nervous system development. Finally, we find strong evidence that specific interspersed repeat families have contributed potentially key developmental enhancers via co-option. Our analysis expands the methodologies available for extracting the richness of information found in genome-wide functional maps. PMID:24009522

Wenger, Aaron M; Clarke, Shoa L; Notwell, James H; Chung, Tisha; Tuteja, Geetu; Guturu, Harendra; Schaar, Bruce T; Bejerano, Gill

2013-08-01

189

In vivo mn-enhanced MRI for early tumor detection and growth rate analysis in a mouse medulloblastoma model.  

PubMed

Mouse models have increased our understanding of the pathogenesis of medulloblastoma (MB), the most common malignant pediatric brain tumor that often forms in the cerebellum. A major goal of ongoing research is to better understand the early stages of tumorigenesis and to establish the genetic and environmental changes that underlie MB initiation and growth. However, studies of MB progression in mouse models are difficult due to the heterogeneity of tumor onset times and growth patterns and the lack of clinical symptoms at early stages. Magnetic resonance imaging (MRI) is critical for noninvasive, longitudinal, three-dimensional (3D) brain tumor imaging in the clinic but is limited in resolution and sensitivity for imaging early MBs in mice. In this study, high-resolution (100 ?m in 2 hours) and high-throughput (150 ?m in 15 minutes) manganese-enhanced MRI (MEMRI) protocols were optimized for early detection and monitoring of MBs in a Patched-1 (Ptch1) conditional knockout (CKO) model. The high tissue contrast obtained with MEMRI revealed detailed cerebellar morphology and enabled detection of MBs over a wide range of stages including pretumoral lesions as early as 2 to 3 weeks postnatal with volumes close to 0.1 mm(3). Furthermore, longitudinal MEMRI allowed noninvasive monitoring of tumors and demonstrated that lesions within and between individuals have different tumorigenic potentials. 3D volumetric studies allowed quantitative analysis of MB tumor morphology and growth rates in individual Ptch1-CKO mice. These results show that MEMRI provides a powerful method for early in vivo detection and longitudinal imaging of MB progression in the mouse brain. PMID:25499213

Suero-Abreu, Giselle A; Praveen Raju, G; Aristizábal, Orlando; Volkova, Eugenia; Wojcinski, Alexandre; Houston, Edward J; Pham, Diane; Szulc, Kamila U; Colon, Daniel; Joyner, Alexandra L; Turnbull, Daniel H

2014-12-01

190

Gamma Interferon Enhances Internalization and Early Nonoxidative Killing of Salmonella enterica Serovar Typhimurium by Human Macrophages and Modifies Cytokine Responses  

PubMed Central

Gamma interferon (IFN-?) is a critical cytokine in host defense against salmonella infections, but its role in phagocytic killing of intracellular Salmonella spp. has been investigated mainly in animal rather than human cells. We measured the effect of recombinant IFN-? (rIFN-?) priming on bacterial internalization, intracellular killing, oxidative burst, and cytokine release during phagocytosis of Salmonella enterica serovar Typhimurium by human monocyte-derived macrophages (MDM). Eleven-day-old MDM, primed for 72 h with rIFN-? (100 ng/ml) exhibited an increased proportion of cells with associated bacteria (31% versus 26%, P = 0.036) and a 67% increase in internalized bacteria per cell compared to unprimed cells (P = 0.025). Retrieval of viable bacteria following internalization was reduced 3.6-fold in 72-h primed versus unprimed MDM (interquartile range, 3.1 to 6.4) at 0.5 h due to enhanced early intracellular killing, and this difference was maintained up to 24 h. In contrast, cells primed for only 24 h exhibited no increase in early killing. MDM were competent to produce an early oxidative burst when stimulated with phorbol myristate acetate, which was fully abrogated by the respiratory burst inhibitor diphenyleneiodonium chloride (DPI), but infection of MDM with S. enterica serovar Typhimurium did not cause an increase in the early respiratory burst under unprimed or primed conditions, and DPI had no effect on the early killing of bacteria by primed or unprimed MDM. During 24 h following infection, rIFN-?-primed MDM released more interleukin-12 (IL-12) and less IL-10 relative to unprimed cells. We conclude that 72-h priming with rIFN-? increases the efficiency of internalization and nonoxidative early intracellular killing of S. enterica serovar Typhimurium by human macrophages and modifies subsequent cytokine release. PMID:15908373

Gordon, Melita A.; Jack, Dominic L.; Dockrell, David H.; Lee, Margaret E.; Read, Robert C.

2005-01-01

191

In Vivo Mn-Enhanced MRI for Early Tumor Detection and Growth Rate Analysis in a Mouse Medulloblastoma Model12  

PubMed Central

Mouse models have increased our understanding of the pathogenesis of medulloblastoma (MB), the most common malignant pediatric brain tumor that often forms in the cerebellum. A major goal of ongoing research is to better understand the early stages of tumorigenesis and to establish the genetic and environmental changes that underlie MB initiation and growth. However, studies of MB progression in mouse models are difficult due to the heterogeneity of tumor onset times and growth patterns and the lack of clinical symptoms at early stages. Magnetic resonance imaging (MRI) is critical for noninvasive, longitudinal, three-dimensional (3D) brain tumor imaging in the clinic but is limited in resolution and sensitivity for imaging early MBs in mice. In this study, high-resolution (100 ?m in 2 hours) and high-throughput (150 ?m in 15 minutes) manganese-enhanced MRI (MEMRI) protocols were optimized for early detection and monitoring of MBs in a Patched-1 (Ptch1) conditional knockout (CKO) model. The high tissue contrast obtained with MEMRI revealed detailed cerebellar morphology and enabled detection of MBs over a wide range of stages including pretumoral lesions as early as 2 to 3 weeks postnatal with volumes close to 0.1 mm3. Furthermore, longitudinal MEMRI allowed noninvasive monitoring of tumors and demonstrated that lesions within and between individuals have different tumorigenic potentials. 3D volumetric studies allowed quantitative analysis of MB tumor morphology and growth rates in individual Ptch1-CKO mice. These results show that MEMRI provides a powerful method for early in vivo detection and longitudinal imaging of MB progression in the mouse brain. PMID:25499213

Suero-Abreu, Giselle A.; Praveen Raju, G.; Aristizábal, Orlando; Volkova, Eugenia; Wojcinski, Alexandre; Houston, Edward J.; Pham, Diane; Szulc, Kamila U.; Colon, Daniel; Joyner, Alexandra L.; Turnbull, Daniel H.

2014-01-01

192

Fiber optic probe enabled by surface-enhanced Raman scattering for early diagnosis of potential acute rejection of kidney transplant  

NASA Astrophysics Data System (ADS)

We have explored the use of a fiber-optic probe with surface-enhanced Raman scattering (SERS) sensing modality for early, noninvasive and, rapid diagnosis of potential renal acute rejection (AR) and other renal graft dysfunction of kidney transplant patients. Multimode silica optical fiber immobilized with colloidal Ag nanoparticles at the distal end was used for SERS measurements of as-collected urine samples at 632.8 nm excitation wavelength. All patients with abnormal renal graft function (3 AR episodes and 2 graft failure episodes) who were clinically diagnosed independently show common unique SERS spectral features in the urines collected just one day after transplant. SERS-based fiber-optic probe has excellent potential to be a bedside tool for early diagnosis of kidney transplant patients for timely medical intervention of patients at high risk of transplant dysfunction.

Chi, Jingmao; Chen, Hui; Tolias, Peter; Du, Henry

2014-06-01

193

Acute arterial occlusion - kidney  

MedlinePLUS

Acute renal arterial thrombosis; Renal artery embolism; Acute renal artery occlusion; Embolism - renal artery ... kidneys need a good blood supply. The main artery to the kidney is called the renal artery. ...

194

Early experiences of endoscopic procedures in general surgery assisted by a computer-enhanced surgical system  

Microsoft Academic Search

  We performed a variety of complete total endoscopic general surgical procedures, including colon resection, distal gastrectomy,\\u000a and splenectomy, successfully with the assistance of the da Vinci computer-enhanced surgical system. The robotic system allowed\\u000a us to manipulate the endoscopic instruments as effectively as during open surgery. It enhanced visualization of both the operative\\u000a field and precision of the necessary techniques, as

M. Hashizume; M. Shimada; M. Tomikawa; Y. Ikeda; I. Takahashi; R. Abe; F. Koga; N. Gotoh; K. Konishi; S. Maehara; K. Sugimachi

2002-01-01

195

15-HETE mediates sub-acute hypoxia-induced TRPC1 expression and enhanced capacitative calcium entry in rat distal pulmonary arterial myocytes.  

PubMed

Sub-acute hypoxia causes pulmonary vasoconstriction (HPV) is associated with increased intracellular Ca(2+) concentration ([Ca(2+)](i)) and contraction of pulmonary arterial smooth muscle cells (PASMCs). We previous have demonstrated that 15-hydroxyeicosatetraenoic acid (15-HETE), a metabolite of arachidonic acid by 15-lipoxygenase (15-LO), causes elevated [Ca(2+)](i) in PASMCs partly through Ca(2+) entry via other than L-type Ca(2+) channels. In this study, we used SKF96365/La(3+) (SOCC antagonists) and Nordihydro-guiairetic acid (NDGA, a blockage of 15-LO) to examine the effect of 15-HETE on capacitative Ca(2+) entry and activity/expression of store-operated Ca(2+) channels (SOCCs) during sub-acute hypoxic procedure and the contribution of SOCCs on the maintenance of vascular tones. The results showed that the 15-HETE induced constriction of PA rings from normoxic and sub-acute hypoxic rats can be abolished by SKF96365 and La(3+). Capacitative Ca(2+) entry (CCE) was also enhanced in PASMCs cultured with 15-HETE under sub-acute hypoxic condition (3% O(2), 48h) and incubation with NDGA in PASMCs can greatly suppress this enhancement. Moreover, TRPC1, not TRPC4 and TRPC6, mRNA and protein expression were increased in PASMCs during these procedures. Meanwhile, the effect of 15-HETE on CCE and TRPC1 expression under sub-acute hypoxic cultivation were greatly suppressed in 15-LO knockdown PASMCs and PAs. These results suggest that 15-HETE mediated HPV through increased TRPC1 expression, leading to enhanced CCE, contributing to the maintenance of vascular tone. PMID:20599518

Li, Shanshan; Ran, Yajuan; Zheng, Xiaodong; Pang, Xiaoping; Wang, Zhigang; Zhang, Rong; Zhu, Daling

2010-09-01

196

The 21bp repeat element of the human cytomegalovirus major immediate early enhancer is a negative regulator of gene expression in undifferentiated cells.  

PubMed Central

The major immediate early regulatory region of human cytomegalovirus (HCMV) has a complex set of DNA sites through which both cellular and viral factors coordinately regulate immediate early gene expression. In undifferentiated human teratocarcinoma (T2) cells we have previously shown that major immediate early gene expression is repressed by a differentiation specific nuclear factor MBF1, which binds to the imperfect dyad symmetry located upstream of the enhancer. However, upon differentiation MBF1 decreases resulting in immediate early gene expression. In this study we show, by mobility shift analysis that the same or similar factor(s) also binds to the 21bp repeat of the major immediate early enhancer. Deletion of this 21bp repeat from the immediate early enhancer expression vectors results in increased CAT expression in undifferentiated T2 cells, to levels similar to that in differentiated cells. Consequently, the 21bp repeat of the HCMV enhancer also acts to negatively regulate major immediate early enhancer function in non-permissive cells. Images PMID:1851560

Kothari, S; Baillie, J; Sissons, J G; Sinclair, J H

1991-01-01

197

Assessment of early tumor response to cytotoxic chemotherapy with dynamic contrast-enhanced ultrasound in human breast cancer xenografts.  

PubMed

There is a strong need to assess early tumor response to chemotherapy in order to avoid adverse effects from unnecessary chemotherapy and allow early transition to second-line therapy. This study was to quantify tumor perfusion changes with dynamic contrast-enhanced ultrasound (CEUS) in the evaluation of early tumor response to cytotoxic chemotherapy. Sixty nude mice bearing with MCF-7 breast cancer were administrated with either adriamycin or sterile saline. CEUS was performed on days 0, 2, 4 and 6 of the treatment, in which time-signal intensity (SI) curves were obtained from the intratumoral and depth-matched liver parenchyma. Four perfusion parameters including peak enhancement (PE), area under the curve of wash-in (WiAUC), wash-in rate (WiR) and wash-in perfusion index (WiPI) were calculated from perfusion curves and normalized with respect to perfusion of adjacent liver parenchyma. Histopathological analysis was conducted to evaluate tumor perfusion, tumor cell density, microvascular density (MVD) and proliferating cell density. Significant decreases of tumor normalized perfusion parameters (i.e., nPE, nWiAUC, nWiR and nWiPI) were noticed between adriamycin-treated and control groups (P<0.01) 2 days after therapy. There were significant differences of tumor volumes between control and treated groups on day 6 (P<0.001) while there were no significant differences in tumor volume on days 0, 2 and 4 (P>0.05). Significant decreases of tumor perfusion, tumor cell density, MVD and proliferating cell density were seen in adrianycin-treated group 2 days after therapy when compared to control group (P<0.001). Dynamic CEUS for quantification of tumor perfusion could be used for early detection of cancer response to cytotoxic chemotherapy prior to notable tumor shrinkage. PMID:23469274

Wang, Jian-Wei; Zheng, Wei; Liu, Ji-Bin; Chen, Yao; Cao, Long-Hui; Luo, Rong-Zhen; Li, An-Hua; Zhou, Jian-Hua

2013-01-01

198

Brief Report: Can Metrics of Reporting Bias Enhance Early Autism Screening Measures?  

ERIC Educational Resources Information Center

The goal of the current study was to develop and pilot the utility of two simple internal response bias metrics, over-reporting and under-reporting, in terms of additive clinical value within common screening practices for early detection of autism spectrum disorder risk. Participants were caregivers and children under 36 months of age (n = 145)…

Taylor, Cora M.; Vehorn, Alison; Noble, Hylan; Weitlauf, Amy S.; Warren, Zachary E.

2014-01-01

199

Enhancing the passing moments: An educational criticism of family visits to an early childhood science exhibition  

Microsoft Academic Search

This educational criticism describes and interprets the nature of family visits to an early childhood science exhibition, Working Wonders, at The Science Centre in Calgary, Alberta. The specific exhibits are described and features that contributed to exhibit popularity are examined. Examples of visitors' interactions with each exhibit are given. The visit experiences of four families are described in detail and

Elizabeth Ann Munroe

1997-01-01

200

Enhancing Early Numeracy by Promoting the Abstract Thought Involved in the Oddity Principle, Seriation, and Conservation  

ERIC Educational Resources Information Center

Although many students who enter kindergarten are cognitively ready to meet the demands of the kindergarten mathematics curriculum, some students arrive without the early abstract reasoning abilities necessary to benefit from the instruction provided. Those who do not possess key cognitive abilities, including understandings of conservation,…

Kidd, Julie K.; Pasnak, Robert; Gadzichowski, Marinka; Ferral-Like, Melissa; Gallington, Debbie

2008-01-01

201

Enhancing Student Services at Owens Community College: Early Results from the Opening Doors Demonstration in Ohio  

ERIC Educational Resources Information Center

MDRC launched Opening Doors in 2003 to study the effects of community college programs designed to help students persist in school and earn a credential. This report presents early results from the Opening Doors program at Owens Community College in Toledo, Ohio, which operated from 2004 through 2006. The two-semester program served students whose…

Scrivener, Susan; Pih, Michael

2007-01-01

202

Genetic Enhancement of Cold Tolerance in Sorghum: Mapping of QTL's for early season cold tolerance  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sorghum is known for its drought tolerance and overall adaptation to high temperature. However, it generally lacks cold tolerance and is vulnerable to cooler temperature specifically during stand establishment in early season planting from April to May in most areas of the US sorghum belt. Stand e...

203

Enhanced early-life nutrition promotes hormone production and reproductive development in Holstein bulls.  

PubMed

Holstein bull calves often reach artificial insemination centers in suboptimal body condition. Early-life nutrition is reported to increase reproductive performance in beef bulls. The objective was to determine whether early-life nutrition in Holstein bulls had effects similar to those reported in beef bulls. Twenty-six Holstein bull calves were randomly allocated into 3 groups at approximately 1 wk of age to receive a low-, medium-, or high-nutrition diet, based on levels of energy and protein, from 2 to 31 wk of age. Calves were on their respective diets until 31 wk of age, after which they were all fed a medium-nutrition diet. To evaluate secretion profiles and concentrations of blood hormones, a subset of bulls was subjected to intensive blood sampling every 4 wk from 11 to 31 wk of age. Testes of all bulls were measured once a month; once scrotal circumference reached 26cm, semen collection was attempted (by electroejaculation) every 2 wk to confirm puberty. Bulls were maintained until approximately 72 wk of age and then slaughtered at a local abattoir. Testes were recovered and weighed. Bulls fed the high-nutrition diet were younger at puberty (high=324.3 d, low=369.3 d) and had larger testes for the entire experimental period than bulls fed the low-nutrition diet. Bulls fed the high-nutrition diet also had an earlier and more substantial early rise in LH than those fed the low-nutrition diet and had increased concentrations of insulin-like growth factor-I (IGF-I) earlier than the bulls fed the low-nutrition diet. Furthermore, we detected a temporal association between increased IGF-I concentrations and an early LH rise in bulls fed the high-nutrition diet. Therefore, we inferred that IGF-I had a role in regulating the early gonadotropin rise (in particular, LH) and thus reproductive development of Holstein bulls. Overall, these results support our hypothesis that Holstein bull calves fed a high-nutrition diet reach puberty earlier and have larger testes than those fed a low-nutrition diet, and they provide clear evidence that nutritional modulation of Holstein bull calves during early life has profound effects on reproductive development. PMID:25497791

Dance, Alysha; Thundathil, Jacob; Wilde, Randy; Blondin, Patrick; Kastelic, John

2015-02-01

204

Arterial conduits for hepatic artery revascularisation in adult liver transplantation.  

PubMed

Arterial complications after orthotopic liver transplantation (OLT), including hepatic artery thrombosis (HAT), are important causes of early graft failure. The use of an arterial conduit is an accepted alternative to the utilisation of native recipient hepatic artery for specific indications. This study aims to determine the efficacy of arterial conduits and the outcome in OLT. We retrospectively reviewed 1,575 cadaveric adult OLTs and identified those in which an arterial conduit was used for hepatic revascularisation. Data on the primary disease, indication for using arterial conduit, type of vascular graft, operative technique and outcome were obtained. Thirty-six (2.3%) patients underwent OLT in which arterial conduits were used for hepatic artery (HA) revascularisation. Six of these were performed on the primary transplant, while the rest (n=30) were performed in patients undergoing re-transplantation, including six who had developed hepatic artery aneurysms. The incidence of arterial conduits was 0.4% (6/1,426 cases) in all primary OLTs and 20.1% (30/149 cases) in all re-transplants. Twenty-nine procedures utilised iliac artery grafts from the same donor as the liver, six used iliac artery grafts from a different donor, and a single patient underwent a polytetrafluoroethylene (PTFE) graft. Two techniques were used: infra-renal aorto-hepatic artery conduit and interposition between the donor and recipient native HAs, or branches of the HAs. The 30-day mortality rate for operations using an arterial conduit was 30.6%. Three conduits thrombosed at 9, 25 and 155 months, respectively, but one liver graft survived without re-transplantation. The arterial conduits had 1- and 5-year patency rates of 88.5% and 80.8%. The 1- and 5-year patient survival rates were 66.7% and 44%. We can thus conclude that an arterial conduit is a viable alternative option for hepatic revascularisation in both primary and re-transplantation. Despite a lower patency rate than that of native HA in the primary OLT group, the outcomes of arterial conduit patency and patient survival rates are both acceptable at 1 and 5 years, especially in the much larger re-OLT group. PMID:15107973

Muralidharan, Vijayaragavan; Imber, Charles; Leelaudomlipi, Surasak; Gunson, Bridget K; Buckels, John A C; Mirza, Darius F; Mayer, A David; Bramhall, Simon R

2004-05-01

205

Detection of early carious lesions using contrast enhancement with coherent light scattering (speckle imaging)  

NASA Astrophysics Data System (ADS)

Currently, dental caries still represent one of the chronic diseases with the highest prevalence and present in most countries. The interaction between light and teeth (absorption, scattering and fluorescence) is intrinsically connected to the constitution of the dental tissue. Decay induced mineral loss introduces a shift in the optical properties of the affected tissue; therefore, study of these properties may produce novel techniques aimed at the early diagnosis of carious lesions. Based on the optical properties of the enamel, we demonstrate the application of first-order spatial statistics in laser speckle imaging, allowing the detection of carious lesions in their early stages. A highlight of this noninvasive, non-destructive, real time and cost effective approach is that it allows a dentist to detect a lesion even in the absence of biofilm or moisture.

Deana, A. M.; Jesus, S. H. C.; Koshoji, N. H.; Bussadori, S. K.; Oliveira, M. T.

2013-07-01

206

Folic Acid Enhances Early Functional Recovery in a Piglet Model of Pediatric Head Injury  

Microsoft Academic Search

For stroke and spinal cord injury, folic acid supplementation has been shown to enhance neurodevelopment and to provide neuroprotection. We hypothesized that folic acid would reduce brain injury and improve neurological outcome in a neonatal piglet model of traumatic brain injury (TBI), using 4 experimental groups of 3- to 5-day-old female piglets. Two groups were intubated, anesthetized and had moderate

Maryam Y. Naim; Stuart Friess; Colin Smith; Jill Ralston; Karen Ryall; Mark A. Helfaer; Susan S. Margulies

2010-01-01

207

Musical Training during Early Childhood Enhances the Neural Encoding of Speech in Noise  

ERIC Educational Resources Information Center

For children, learning often occurs in the presence of background noise. As such, there is growing desire to improve a child's access to a target signal in noise. Given adult musicians' perceptual and neural speech-in-noise enhancements, we asked whether similar effects are present in musically-trained children. We assessed the perception and…

Strait, Dana L.; Parbery-Clark, Alexandra; Hittner, Emily; Kraus, Nina

2012-01-01

208

A Report on the Technological Enhancements Project Evaluation: Deepening Early Learning Experiences through Technology  

ERIC Educational Resources Information Center

As part of the "Ready to Learn" Initiative, Education Development Center, Inc. (EDC), was charged with addressing the evaluation of Technological Enhancements for the outreach efforts of three producers: Out of the Blue's Super WHY! Technology Add-On; Sesame Workshop's The Electric Company School's Initiative Curriculum; and WordWorld's eBook…

Hupert, Naomi; Cervantes, Francisco; DeGroof, Emily

2010-01-01

209

The probiotic Escherichia coli Nissle 1917 enhances early gastrointestinal maturation in young turkey poults  

Technology Transfer Automated Retrieval System (TEKTRAN)

Concerns over the use of antibiotics as growth promoters has led to interest in finding alternative growth promoters such as natural compounds and probiotics. Supplementing feed with probiotics has shown to enhance the gastrointestinal tract (GIT) development of chickens and turkeys. The human pro...

210

Enhanced Handling and Positioning in Early Infancy Advances Development throughout the First Year  

ERIC Educational Resources Information Center

Behaviors emerge, in part, from the interplay of infant abilities and caregiver-infant interactions. Cross-cultural and developmental studies suggest caregiver handling and positioning influence infant development. In this prospective, longitudinal study, the effects of 3 weeks of enhanced handling and positioning experiences provided to 14…

Lobo, Michele A.; Galloway, James C.

2012-01-01

211

Arterial embolism  

PubMed Central

Surgical and intensive care patients are at a heightened risk for arterial embolization due to pre-existing conditions such as age, hypercoagulability, cardiac abnormalities and atherosclerotic disease. Most arterial emboli are clots that originate in the heart and travel to distant vascular beds where they cause arterial occlusion, ischemia, and potentially infarction. Other emboli form on the surface of eroded arterial plaque or within its lipid core. Thromboemboli are large clots that dislodge from the surface of athesclerotic lesions and occlude distal arteries causing immediate ischemia. Atheroemboli, which originate from fracturing the lipid core tend to cause a process of organ dysfunction and systemic inflammation, termed cholesterol embolization syndrome. The presentation of arterial emboli depends on the arterial bed that is affected. The most common manifestations are strokes and acute lower limb ischemia. Less frequently, emboli target the upper extremities, mesenteric or renal arteries. Treatment involves rapid diagnosis, which may be aided by precise imaging studies and restoration of blood flow. The type of emboli, duration of presentation, and organ system affected determines the treatment course. Long-term therapy includes supportive medical care, identification of the source of embolism and prevention of additional emboli. Patients who experienced arterial embolism as a result of clots formed in the heart should be anticoagulated. Arterial emboli from atherosclerotic disease of the aorta or other large arteries should prompt treatment to reduce the risk for atherosclerotic progression, such as anti-platelet therapy and the use of statin drugs. The use of anticoagulation and surgical intervention to reduce the risk of arterial embolization from atherosclerotic lesions is still being studied. PMID:23724391

Lyaker, Michael R.; Tulman, David B.; Dimitrova, Galina T.; Pin, Richard H.; Papadimos, Thomas J.

2013-01-01

212

Combined contrast-enhanced ultrasound and rt-PA treatment is safe and improves impaired microcirculation after reperfusion of middle cerebral artery occlusion  

PubMed Central

In monitoring of recanalization and in sonothrombolysis, contrast-enhanced ultrasound (CEUS) is applied in extended time protocols. As extended use may increase the probability of unwanted effects, careful safety evaluation is required. We investigated the safety profile and beneficial effects of CEUS in a reperfusion model. Wistar rats were subjected to filament occlusion of the right middle cerebral artery (MCA). Reperfusion was established after 90?minutes, followed by recombinant tissue-type plasminogen activator (rt-PA) treatment and randomization to additional CEUS (contrast agent: SonoVue; 60?minutes). Blinded outcome evaluation consisted of magnetic resonance imaging (MRI), neurologic assessment, and histology and, in separate experiments, quantitative 3D nano-computed tomography (CT) angiography (900?nm3 voxel size). Nano-CT revealed severely compromised microcirculation in untreated animals after MCA reperfusion. The rt-PA partially improved hemispheric perfusion. Impairment was completely reversed in animals receiving rt-PA and CEUS. This combination was more effective than treatment with either CEUS without rt-PA or rt-PA and ultrasound or ultrasound alone. In MRI experiments, CEUS and rt-PA treatment resulted in a significantly reduced ischemic lesion volume and edema formation. No unwanted effects were detected on MRI, histology, and intracranial temperature assessment. This study shows that CEUS and rt-PA is safe in the situation of reperfusion and displays beneficial effects on the level of the microvasculature. PMID:20531462

Nedelmann, Max; Ritschel, Nouha; Doenges, Simone; Langheinrich, Alexander C; Acker, Till; Reuter, Peter; Yeniguen, Mesut; Pukropski, Jan; Kaps, Manfred; Mueller, Clemens; Bachmann, Georg; Gerriets, Tibo

2010-01-01

213

Contrast enhanced ultrasound reveals real-time spatial changes in vascular perfusion during early implantation in the macaque uterus  

PubMed Central

Objective To use contrast enhanced ultrasound (CEU) to quantify blood flow in the macaque uterus during early pregnancy. Design Prospective nonhuman primate study. Setting National Primate Research Center. Animals Naturally cycling female rhesus macaques (Macaca mulatta). Interventions Female macaques were mated on days 11–14 of the cycle. Females were then imaged by CEU and Doppler ultrasound (DUS) once every 3 days from day 21 through day 39 of the fertile cycle. Main Outcome Measures Visualization and quantification of uterine vascular perfusion. Results CEU identified the primary placental disc and underlying vessels ~2 days earlier than DUS was able to observe endometrial thickening. CEU revealed spatial differences in vascular perfusion between the endometrium, myometrium, and the endometrial-myometrial (junctional) zone. Myometrium displayed the highest rate of blood flow (>10 mL/min/g tissue). There was less blood flow in the endometrium and junctional zone (<3 mL/min/g). A brief fall in progesterone was observed during early implantation, which was correlated with reduced blood flow to all three uterine compartments, but did not reduce flow to the placenta. Conclusions CEU provides a sensitive, non-invasive method to assess vascular perfusion of the uterus during embryo implantation in macaques. We propose CEU as a new diagnostic tool to monitor vascular changes associated with early pregnancy in women. PMID:21316046

Keator, Christopher S.; Lindner, Jonathan R.; Belcik, J. Todd; Bishop, Cecily V.; Slayden, Ov D.

2011-01-01

214

High Calcium Bioglass Enhances Differentiation and Survival of Endothelial Progenitor Cells, Inducing Early Vascularization in Critical Size Bone Defects  

PubMed Central

Early vascularization is a prerequisite for successful bone healing and endothelial progenitor cells (EPC), seeded on appropriate biomaterials, can improve vascularization. The type of biomaterial influences EPC function with bioglass evoking a vascularizing response. In this study the influence of a composite biomaterial based on polylactic acid (PLA) and either 20 or 40% bioglass, BG20 and BG40, respectively, on the differentiation and survival of EPCs in vitro was investigated. Subsequently, the effect of the composite material on early vascularization in a rat calvarial critical size defect model with or without EPCs was evaluated. Human EPCs were cultured with ?-TCP, PLA, BG20 or BG40, and seeding efficacy, cell viability, cell morphology and apoptosis were analysed in vitro. BG40 released the most calcium, and improved endothelial differentiation and vitality best. This effect was mimicked by adding an equivalent amount of calcium to the medium and was diminished in the presence of the calcium chelator, EGTA. To analyze the effect of BG40 and EPCs in vivo, a 6-mm diameter critical size calvarial defect was created in rats (n?=?12). Controls (n?=?6) received BG40 and the treatment group (n?=?6) received BG40 seeded with 5×105 rat EPCs. Vascularization after 1 week was significantly improved when EPCs were seeded onto BG40, compared to implanting BG40 alone. This indicates that Ca2+ release improves EPC differentiation and is useful for enhanced early vascularization in critical size bone defects. PMID:24244419

Nguyen Ngoc, Christina; Meier, Simon; Nau, Christoph; Schaible, Alexander; Marzi, Ingo; Henrich, Dirk

2013-01-01

215

[Peripheral arteries].  

PubMed

Peripheral arterial disease is a main cause of morbidity in industrialised countries. It chiefly affects older people. The most common causes are atherosclerosis and vasodilatatory abnormalities. In the presence of unexplained leg symptoms, peripheral arterial disease can be diagnosed or ruled out by non-invasive diagnostic methods such as history, clinical examination and the measurement of ankle and brachial artery pressure by Doppler ultrasound, as well as by calculating the ankle brachial index. Colour coded duplex sonography, computer tomography angiography, magnetic resonance angiography and arteriography are the imaging modalities used. Current diagnostic strategies are analysed for the different peripheral artery diseases. PMID:17479237

Vosshenrich, R; Reimer, P; Landwehr, P

2007-06-01

216

Association of Physical Activity in Childhood and Early Adulthood With Carotid Artery Elasticity 21 Years Later: The Cardiovascular Risk in Young Finns Study  

PubMed Central

Background Decreased arterial elasticity is a risk factor for several cardiovascular outcomes. Longitudinal data on the effect of physical activity in youth on adult arterial elasticity are limited. The aim of this study was to determine the long?term effects of physical activity in children and young adults on carotid artery elasticity after 21 years of follow?up. Methods and Results Participants were 1417 children (aged 9 to 15 years) and 999 young adults (aged 18 to 24 years) from the prospective Cardiovascular Risk in Young Finns Study. Participants had questionnaire measures of leisure?time physical activity available from 1986 and ultrasound?derived indices of carotid artery elasticity measured in 2007. Carotid artery elasticity indices were distensibility (%/10 mm Hg), Young's elastic modulus (kPa), and stiffness index (unitless). Physical activity at age 18 to 24 years was directly associated with distensibility (?=0.068, P=0.014) and inversely with Young's elastic modulus (?=?0.057, P=0.0037) and indirectly with stiffness index (?=?0.050, P=0.0028) 21 years later in males and females. The associations remained after adjustment for age, sex, body mass index, smoking, systolic blood pressure, serum lipids and insulin, and 21?year change in physical activity. At age 9 to 15 years, the favorable association, remaining after adjustment, was found in males (distensibility [?=0.097, P=0.010], Young's elastic modulus [?=?0.060, P=0.028], and stiffness index [?=?0.062, P=0.007]) but not in females (P=0.70, P=0.85, and P=0.91, respectively). Conclusions Leisure?time physical activity in boys and young adults is associated with carotid artery elasticity later in life, suggesting that higher levels of physical activity in youth may benefit future cardiovascular health. PMID:24755150

Pälve, Kristiina S.; Pahkala, Katja; Magnussen, Costan G.; Koivistoinen, Teemu; Juonala, Markus; Kähönen, Mika; Lehtimäki, Terho; Rönnemaa, Tapani; Viikari, Jorma S. A.; Raitakari, Olli T.

2014-01-01

217

Enhanced role for the opening of potassium channels in relaxant responses to acetylcholine after myocardial ischaemia and reperfusion in dog coronary arteries  

PubMed Central

Anaesthetized dogs were subjected to 1?h occlusion of the left circumflex coronary artery followed by 2?h of reperfusion. Relaxant responses were examined in coronary artery rings removed proximal (nonischaemic) or distal (ischaemic) to the site of occlusion. Relaxant responses to acetylcholine (ACh) were similar in nonischaemic and ischaemic artery rings. In addition ACh-induced relaxation of nonischaemic and ischaemic artery rings was equally susceptible to inhibition of nitric oxide (NO) synthase using L-NG-nitroarginine (L-NOARG, 10?4 M), or to inhibition of soluble guanylate cyclase using 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one (ODQ, 10?5 M). In nonischaemic arteries, the relaxation to ACh was unaffected by high K+ (67?mM) but in ischaemic arteries, the maximum relaxation to ACh was significantly reduced from 113±6 to 60±2% (ANOVA, P<0.05). Tetraethylammonium (TEA, 10?3 M), an inhibitor of large conductance calcium activated potassium (BKCa) channels did not inhibit the response to ACh in nonischaemic arteries but in ischaemic arteries TEA significantly shifted the concentration response curve to ACh to the right (pEC50; nonischaemic, 7.07±0.25; ischaemic, 6.54±0.21, P<0.01, ANOVA) without decreasing the maximum relaxation. TEA did not affect the responses to sodium nitroprusside in either nonischaemic or ischaemic arteries. In conclusion, ischaemia/reperfusion did not change the sensitivity of endothelium-dependent relaxation to L-NOARG or ODQ indicating that ischaemia did not affect the contribution of NO or cyclic GMP to ACh-induced relaxation. However, in ischaemic arteries the opening of the BKCa channels contributed to relaxation caused by ACh whereas TEA had no effect in nonischaemic arteries. The factor responsible for the opening of this potassium channel was a factor other than NO and may be endothelium derived hyperpolarizing factor (EDHF). PMID:10193772

Chan, Elsa C H; Woodman, Owen L

1999-01-01

218

Enhancing the passing moments: An educational criticism of family visits to an early childhood science exhibition  

NASA Astrophysics Data System (ADS)

This educational criticism describes and interprets the nature of family visits to an early childhood science exhibition, Working Wonders, at The Science Centre in Calgary, Alberta. The specific exhibits are described and features that contributed to exhibit popularity are examined. Examples of visitors' interactions with each exhibit are given. The visit experiences of four families are described in detail and analyzed. Typical family visitors' reactions, expectations, and experiences are summarized. Because one of the mutual expectations of the granting agency, The Science Centre, and the adult visitors was that a visit to the exhibition would be educational, the family visits are examined for instances of learning and analyzed to determine the factors that influenced the learning. Constructivism forms the basis for understanding the process of learning during family visits. The analysis is supported by reference to research from the fields of museum studies, education, and environmental design. The analysis of the educational significance and potential of family visits to an early childhood exhibition leads to the conclusion that specific features may facilitate learning in such an environment. Those features are represented in a set of guidelines for the development and evaluation of early childhood exhibitions. The guidelines suggest attention must be given to the ambience of the space, the general layout of the space, the exhibits, the copy and graphics, additional programs and information, the subtle influences of the building and the staff, and the learning processes of young children, adults, and intergenerational groups. The guidelines suggest specific issues to consider to develop a space that is stimulating and memorable, responsive to the needs of the two distinct visitor groups (young children and adults), and conducive to learning.

Munroe, Elizabeth Ann

219

Electrocardiograph-triggered two-dimensional time-of-flight versus optimized contrast-enhanced three-dimensional MR angiography of the peripheral arteries.  

PubMed

We determined whether the accuracy of magnetic resonance angiography (MRA) in the peripheral run-off vessels can be improved by using contrast-enhanced (CE) three-dimensional (3D) technique in comparison to electrocardiograph (ECG)-triggered two-dimensional (2D) time-of-flight (TOF) technique. In a prospective study 20 patients with occlusions of the pelvic and/or femoral arteries underwent a CE 3D MRA (repetition time (TR): 5 ms, (TE) echo time: 2 ms, flip angle (FA): 30 degrees ) and an ECG-triggered 2D time-of-flight (TOF) technique (TR: 408 resp. 608 ms, TE: 7 ms, FA: 70 degrees) of the run-off vessels on a 1.5 T MR system. Each patient received a contrast material volume of 0.15 mmol/kg of body weight of gadolinium (Gd)/DTPA using an automatic injector. The tube system to the patient was flushed by 50 mL of a saline solution applied with the same injection rate as the contrast material administration. The start of the 3D MR sequence was tailored individually to the applied contrast material after determination of circulation times by a prior bolus. All patients underwent each conventional or digital arteriography for comparison, as well. The visualization of the run-off vessels was ranked on a scale of 0-3 (0 = poor, 1 = fair, 2 = good, 3 = excellent) by three blinded reviewers. They also graded the vascular segments as either occluded or significantly altered (>50% reduction in diameter) or free of significant stenosis. CE 3D MRA was significantly faster in imaging the run-off vessels in comparison to the ECG-triggered 2D TOF technique. All 160 vascular segments were visualized with the 3D method, whereas only 142/160 segments were seen with 2D technique. The resulting image quality ranking of all vascular segments was significantly higher (p < 0.05) using CE 3D MRA (2.8) than with the 2D TOF technique (2.4). The detection of the stenoses was possible with both techniques. The grading of seven of seven stenoses was correct with 3D method and in five of seven cases with the 2D TOF technique. All vessel occlusions were detected by using both techniques. Small collaterals were visualized in more detail with the CE 3D MR angiography. These data demonstrate an improvement in image quality and accuracy of MRA of the peripheral arteries using a CE 3D technique in comparison to an ECG-triggered 2D TOF sequence. PMID:9814770

Vosshenrich, R; Kopka, L; Castillo, E; Böttcher, U; Graessner, J; Grabbe, E

1998-10-01

220

A model-constrained Monte Carlo method for blind arterial input function estimation in dynamic contrast-enhanced MRI: I. Simulations  

NASA Astrophysics Data System (ADS)

Widespread adoption of quantitative pharmacokinetic modeling methods in conjunction with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has led to increased recognition of the importance of obtaining accurate patient-specific arterial input function (AIF) measurements. Ideally, DCE-MRI studies use an AIF directly measured in an artery local to the tissue of interest, along with measured tissue concentration curves, to quantitatively determine pharmacokinetic parameters. However, the numerous technical and practical difficulties associated with AIF measurement have made the use of population-averaged AIF data a popular, if sub-optimal, alternative to AIF measurement. In this work, we present and characterize a new algorithm for determining the AIF solely from the measured tissue concentration curves. This Monte Carlo blind estimation (MCBE) algorithm estimates the AIF from the subsets of D concentration-time curves drawn from a larger pool of M candidate curves via nonlinear optimization, doing so for multiple (Q) subsets and statistically averaging these repeated estimates. The MCBE algorithm can be viewed as a generalization of previously published methods that employ clustering of concentration-time curves and only estimate the AIF once. Extensive computer simulations were performed over physiologically and experimentally realistic ranges of imaging and tissue parameters, and the impact of choosing different values of D and Q was investigated. We found the algorithm to be robust, computationally efficient and capable of accurately estimating the AIF even for relatively high noise levels, long sampling intervals and low diversity of tissue curves. With the incorporation of bootstrapping initialization, we further demonstrated the ability to blindly estimate AIFs that deviate substantially in shape from the population-averaged initial guess. Pharmacokinetic parameter estimates for Ktrans, kep, vp and ve all showed relative biases and uncertainties of less than 10% for measurements having a temporal sampling rate of 4 s and a concentration measurement noise level of ? = 0.04 mM. A companion paper discusses the application of the MCBE algorithm to DCE-MRI data acquired in eight patients with malignant brain tumors.

Schabel, Matthias C.; Fluckiger, Jacob U.; DiBella, Edward V. R.

2010-08-01

221

Peripheral Arterial Disease in a Symptomatic Diabetic Population: Prospective Comparison of Rapid Unenhanced MR Angiography (MRA) With Contrast-Enhanced MRA  

PubMed Central

OBJECTIVE The joint guidelines of the American College of Cardiology and American Heart Association support the use of contrast-enhanced MR angiography (CEMRA) to diagnose the location and degree of stenosis in patients with known or suspected peripheral arterial disease (PAD). The high prevalence of chronic renal impairment in diabetic patients with PAD and the need for high doses of gadolinium-based contrast agents place them at risk for nephrogenic systemic fibrosis. The purpose of our study was to evaluate the accuracy of the rapid technique of quiescent-interval single-shot (QISS) unenhanced MR angiography (MRA) compared with CEMRA for the diagnosis in diabetic patients referred with symptomatic chronic PAD. SUBJECTS AND METHODS This prospective two-center study evaluated 25 consecutive diabetic patients with documented or suspected symptomatic PAD. Both centers used identical imaging protocols. Images were independently analyzed by two radiologists. A subgroup analysis was performed of patients who were also assessed with digital subtraction angiography (DSA) as part of the standard-of-care protocol before revascularization. RESULTS For this study, 775 segments were analyzed. On a per-segment basis, the mean values of the diagnostic accuracy of unenhanced MRA compared with reference CEMRA for two reviewers, reviewers 1 and 2, were as follows: sensitivity, 87.4% and 92.1%; specificity, 96.8% and 96.0%; positive predictive value, 90.8% and 94.0%; and negative predictive value, 95.5% and 94.6%. Substantial agreement was found when overall DSA results were compared with QISS unenhanced MRA (? = 0.68) and CEMRA (? = 0.63) in the subgroup of patients who also underwent DSA. There was almost perfect agreement between the two readers for stenosis scores, with Cohen’s kappa values being greater than 0.80 for both MRA techniques. CONCLUSION The results of our study indicate that QISS unenhanced MRA is an accurate noncontrast alternative to CEMRA for showing clinically significant arterial disease in patients with diabetes with symptomatic PAD. PMID:22109304

Hodnett, Philip A.; Ward, Emily V.; Davarpanah, Amir H.; Scanlon, Timothy G.; Collins, Jeremy D.; Glielmi, Christopher B.; Bi, Xiaoming; Koktzoglou, Ioannis; Gupta, Navyash; Carr, James C.; Edelman, Robert R.

2011-01-01

222

HIV-1 induces the formation of stable microtubules to enhance early infection  

PubMed Central

Summary Stable microtubule (MT) subsets form distinct networks from dynamic MTs and acquire distinguishing posttranslational modifications, notably detyrosination and acetylation. Acting as specialized tracks for vesicle and macromolecular transport, their formation is regulated by the end-binding protein, EB1, which recruits proteins that stabilize MTs. We show that HIV-1 induces the formation of acetylated and detyrosinated stable MTs early in infection. Although the MT depolymerizing agent nocodazole affected dynamic MTs, HIV-1 particles localized to nocodazole-resistant stable MTs and infection was minimally affected. EB1 depletion or expression of an EB1 carboxy-terminal fragment that acts as a dominant negative inhibitor of MT stabilization, prevented HIV-1-induced stable MT formation and suppressed early viral infection. Furthermore, we show that the HIV-1 matrix protein targets the EB1-binding protein, Kif4 to induce MT stabilization. Our findings illustrate how specialized MT-binding proteins mediate MT stabilization by HIV-1 and the importance of stable MT subsets in viral infection. PMID:24237699

Sabo, Yosef; Walsh, Derek; Barry, Denis S.; Tinaztepe, Sedef; de los Santos, Kenia; Goff, Stephen P.; Gundersen, Gregg G.; Naghavi, Mojgan H.

2013-01-01

223

Surface enhanced Raman spectroscopic (SERS) study of saliva in the early detection of oral cancer  

NASA Astrophysics Data System (ADS)

Worldwide, oral cancer is the sixth most common cancer for both sexes. In Singapore, the 5-year survival rate of oral cancer is about 50%. The high mortality rate has been attributed to the difficulties in detecting the disease in an early treatable stage. Currently, the standard screening procedures for oral cancer are histopathology examination of biopsied tissues and exfoliative cytological assessment. These techniques, unfortunately, are low in sensitivity. In this study, we exploit the high amplification factor of SERS to investigate on the possibility of utilising molecular vibrational information from saliva samples to detect oral cancer early. All raw saliva samples were centrifuged at 13,000 krpm for 5 minutes to remove unwanted particles prior to SERS measurements. The purified saliva samples were then applied directly on gold particle films, followed by excitation with a 633 nm HeNe laser. SERS spectrum can be obtained in less than 2 minutes for each sample. We have studied the saliva spectra acquired from 5 normal individuals and 5 patients with oral cancer. In addition, we also observe new peaks at 1097 cm-1 and 1627 cm-1 in some of the abnormal samples. These peaks are not present in the spectra acquired from the normal samples. Preliminary measurements will be presented. This study may lead to the development of a sensitive and portable diagnostics system for oral cancer.

Kho, Kiang W.; Malini, Olivo; Shen, Ze Xiang; Soo, Khee Chee

2005-03-01

224

Institutional report - Valves Is the aortic valve pathology type different for early and late mortality in concomitant aortic valve replacement and coronary artery bypass surgery?  

Microsoft Academic Search

We assessed the effects of aortic valve pathology type on the long-term outcomes of patients who underwent concomitant aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) surgery. We retrospectively reviewed 150 patients who underwent AVR- CABG at our institution between January 1997 and December 2006. We divided patients into aortic stenosis (AS), aortic regurgitation (AR), and mixed-type groups

Rafet Gunay; Yavuz Sensoz; Ilyas Kayacioglu; Abdullah Kemal Tuygun; Ahmet Yavuz Balci; Ugur Kisa; Mahmut Murat Demirtas; Ibrahim Yekeler

225

Coronary artery spasm  

MedlinePLUS

Coronary artery spasm is a temporary, sudden narrowing of one of the coronary arteries (the arteries that supply blood to ... with angina (chest pain and pressure) have coronary artery spasm. Coronary artery spasm occurs most commonly in people ...

226

Novel Polypyrrole-Coated Polylactide Scaffolds Enhance Adipose Stem Cell Proliferation and Early Osteogenic Differentiation  

PubMed Central

An electrically conductive polypyrrole (PPy) doped with a bioactive agent is an emerging functional biomaterial for tissue engineering. We therefore used chondroitin sulfate (CS)-doped PPy coating to modify initially electrically insulating polylactide resulting in novel osteogenic scaffolds. In situ chemical oxidative polymerization was used to obtain electrically conductive PPy coating on poly-96L/4D-lactide (PLA) nonwoven scaffolds. The coated scaffolds were characterized and their electrical conductivity was evaluated in hydrolysis. The ability of the coated and conductive scaffolds to enhance proliferation and osteogenic differentiation of human adipose stem cells (hASCs) under electrical stimulation (ES) in three-dimensional (3D) geometry was compared to the noncoated PLA scaffolds. Electrical conductivity of PPy-coated PLA scaffolds (PLA-PPy) was evident at the beginning of hydrolysis, but decreased during the first week of incubation due to de-doping. PLA-PPy scaffolds enhanced hASC proliferation significantly compared to the plain PLA scaffolds at 7 and 14 days. Furthermore, the alkaline phosphatase (ALP) activity of the hASCs was generally higher in PLA-PPy seeded scaffolds, but due to patient variation, no statistical significance could be determined. ES did not have a significant effect on hASCs. This study highlights the potential of novel PPy-coated PLA scaffolds in bone tissue engineering. PMID:23126228

Pelto, Jani; Björninen, Miina; Pälli, Aliisa; Talvitie, Elina; Hyttinen, Jari; Mannerström, Bettina; Suuronen Seppanen, Riitta; Kellomäki, Minna; Miettinen, Susanna; Haimi, Suvi

2013-01-01

227

INTRAUTERINE EXPOSURE TO LEAD MAY ENHANCE SENSITIZATION TO COMMON INHALANT ALLERGENS IN EARLY CHILDHOOD. A PROSPECTIVE PREBIRTH COHORT STUDY  

PubMed Central

Background Several in vivo and in vitro studies have shown that metal-rich particles may enhance allergic responses to house dust mites and induce an increased release of allergy-related cytokines. Objectives The main goal of this analysis is to define the possible association of intrauterine exposure to lead and mercury with the occurrence of skin sensitization to common aeroallergens in early childhood. Material and Methods The present study refers to a sample of 224 women in the second trimester of pregnancy recruited from Krakow inner city area who had full term pregnancies and whose children underwent skin prick testing (SPT) at the age of 5. Lead and mercury levels were assessed in cord blood and retested in children at age of 5 years. Aeroallergen concentrations in house dust were measured at the age of 3 years. The main health outcome (atopic status) was defined as the positive SPT to at least one common aeroallergen (Der f1, Der p1, Can f1 and Fel d1) at the age of 5 years. In the statistical analysis of the association between atopic status of children and exposure to metals, the study considered a set of covariates such as maternal characteristics (age, education, atopy), child’s gender, number of older siblings, prenatal (measured via cord blood cotinine) and postnatal environmental tobacco smoke together with exposure to polycyclic aromatic hydrocarbons (PAH) as measured by PAH-DNA adducts. Results and conclusion In the binary regression analysis, which controlled for the confounders, the risk ratio (RR) estimate for atopic sensitization was significantly associated with the lead exposure (RR =2.25, 95%CI: 1.21–4.19). In conclusion, the data suggest that even very low-level of prenatal lead exposure may be implicated in enhancing sensitization to common aeroallergens in early childhood. PMID:21094490

Jedrychowski, Wieslaw; Perera, Frederica; Maugeri, Umberto; Miller, Rachel L.; Rembiasz, Maria; Flak, Elzbieta; Mroz, Elzbieta; Majewska, Renata; Zembala, Marek

2010-01-01

228

Brief report: can metrics of reporting bias enhance early autism screening measures?  

PubMed

The goal of the current study was to develop and pilot the utility of two simple internal response bias metrics, over-reporting and under-reporting, in terms of additive clinical value within common screening practices for early detection of autism spectrum disorder risk. Participants were caregivers and children under 36 months of age (n = 145) participating in first-time diagnostic appointments across our clinical research center due to developmental concerns. Caregivers were asked to complete the Modified Checklist for Autism in Toddlers (MCHAT) as well as a questionnaire embedding six response bias indicator questions. These questions were items that in previous clinical studies had been endorsed by an overwhelming majority of parents within clinically identified populations. Results indicated that removal of self-reports indicative of potential response bias dramatically reduced both false positives and false negatives on the MCHAT within this sample. This suggests that future work developing internal metrics of response bias may be promising in addressing limits of current screening measures and practices. PMID:24682706

Taylor, Cora M; Vehorn, Alison; Noble, Hylan; Weitlauf, Amy S; Warren, Zachary E

2014-09-01

229

Early life adversity reduces stress reactivity and enhances impulsive behavior: Implications for health behaviors  

PubMed Central

Altered reactivity to stress, either in the direction of exaggerated reactivity or diminished reactivity, may signal a dysregulation of systems intended to maintain homeostasis and a state of good health. Evidence has accumulated that diminished reactivity to psychosocial stress may signal poor health outcomes. One source of diminished cortisol and autonomic reactivity is the experience of adverse rearing during childhood and adolescence. The Oklahoma Family Health Patterns Project has examined a cohort of 426 healthy young adults with and without a family history of alcoholism. Regardless of family history, persons who had experienced high degrees of adversity prior to age 16 had a constellation of changes including reduced cortisol and heart rate reactivity, diminished cognitive capacity, and unstable regulation of affect, leading to behavioral impulsivity and antisocial tendencies. We present a model whereby this constellation of physiological, cognitive, and affective tendencies is consistent with altered central dopaminergic activity leading to changes in brain function that may foster impulsive and risky behaviors. These in turn may promote greater use of alcohol other drugs along with adopting poor health behaviors. This model provides a pathway from early life adversity to low stress reactivity that forms a basis for risky behaviors and poor health outcomes. PMID:23085387

Lovallo, William R.

2012-01-01

230

Otx2 and Oct4 Drive Early Enhancer Activation during Embryonic Stem Cell Transition from Naive Pluripotency  

PubMed Central

Summary Embryonic stem cells (ESCs) are unique in that they have the capacity to differentiate into all of the cell types in the body. We know a lot about the complex transcriptional control circuits that maintain the naive pluripotent state under self-renewing conditions but comparatively less about how cells exit from this state in response to differentiation stimuli. Here, we examined the role of Otx2 in this process in mouse ESCs and demonstrate that it plays a leading role in remodeling the gene regulatory networks as cells exit from ground state pluripotency. Otx2 drives enhancer activation through affecting chromatin marks and the activity of associated genes. Mechanistically, Oct4 is required for Otx2 expression, and reciprocally, Otx2 is required for efficient Oct4 recruitment to many enhancer regions. Therefore, the Oct4-Otx2 regulatory axis actively establishes a new regulatory chromatin landscape during the early events that accompany exit from ground state pluripotency. PMID:24931607

Yang, Shen-Hsi; Kalkan, Tüzer; Morissroe, Claire; Marks, Hendrik; Stunnenberg, Hendrik; Smith, Austin; Sharrocks, Andrew D.

2014-01-01

231

RNA-Seq defines novel genes, RNA processing patterns and enhancer maps for the early stages of nephrogenesis: Hox supergenes  

PubMed Central

During kidney development the cap mesenchyme progenitor cells both self renew and differentiate into nephrons. The balance between renewal and differentiation determines the final nephron count, which is of considerable medical importance. An important goal is to create a precise genetic definition of the early differentiation of cap mesenchyme progenitors. We used RNA-Seq to transcriptional profile the cap mesenchyme progenitors and their first epithelial derivative, the renal vesicles. The results provide a global view of the changing gene expression program during this key period, defining expression levels for all transcription factors, growth factors, and receptors. The RNA-Seq was performed using two different biochemistries, with one examining only polyadenylated RNA and the other total RNA. This allowed the analysis of noncanonical transcripts, which for many genes were more abundant than standard exonic RNAs. Since a large fraction of enhancers are now known to be transcribed the results also provide global maps of potential enhancers. Further, the RNA-Seq data defined hundreds of novel splice patterns and large numbers of new genes. Particularly striking was the extensive sense/antisense transcription and changing RNA processing complexities of the Hox clusters. PMID:22664176

Brunskill, Eric W; Potter, S. Steven

2012-01-01

232

Vaccination Enhances Early Immune Responses in White Shrimp Litopenaeus vannamei after Secondary Exposure to Vibrio alginolyticus  

PubMed Central

Background Recent work suggested that the presence of specific memory or some form of adaptive immunity occurs in insects and shrimp. Hypervariable pattern recognition molecules, known as Down syndrome cell adhesion molecules, are able to mount specific recognition, and immune priming in invertebrates. In the present study, we attempted to understand the immune response pattern of white shrimp Litopenaeus vannamei which received primary (PE) and secondary exposure (SE) to Vibrio alginolyticus. Methodology Immune parameters and proliferation of haematopoietic tissues (HPTs) of shrimp which had received PE and SE to V. alginolyticus were measured. In the PE trial, the immune parameters and proliferation of HPTs of shrimp that received heat-killed V. alginolyticus (HVa) and formalin-inactivated V. alginolyticus (FVa) were measured. Mortality, immune parameters and proliferation of HPTs of 7-day-HVa-PE shrimp (shrimp that received primary exposure to HVa after 7 days) and 7-day-FVa-PE shrimp (shrimp that received primary exposure to FVa after 7 days) following SE to live V. alginolyticus (LVa) were measured. Phagocytic activity and clearance efficiency were examined for the 7?35-day-HVa-PE and FVa-PE shrimp. Results HVa-receiving shrimp showed an earlier increase in the immune response on day 1, whereas FVa-receiving shrimp showed a late increase in the immune response on day 5. The 7-day-FVa-PE shrimp showed enhancement of immunity when encountering SE to LVa, whereas 7-day-HVa-PE shrimp showed a minor enhancement in immunity. 7-day-FVa-PE shrimp showed higher proliferation and an HPT mitotic index. Both phagocytic activity and clearance maintained higher for both HVa-PE and FVa-PE shrimp after 28 days. Conclusions HVa- and FVa-receiving shrimp showed the bacteria agglutinated prior to being phagocytised. FVa functions as a vaccine, whereas HVa functions as an inducer and can be used as an immune adjuvant. A combined mixture of FVa and HVa can serve as a “vaccine component” to modulate the immunity of shrimp. PMID:23894531

Lin, Yong-Chin; Chen, Jiann-Chu; Morni, Wan Zabidii W.; Putra, Dedi Fazriansyah; Huang, Chien-Lun; Li, Chang-Che; Hsieh, Jen-Fang

2013-01-01

233

Scar detection by contrast-enhanced magnetic resonance imaging in chronic coronary artery disease: a comparison with nuclear imaging and echocardiography.  

PubMed

We compared contrast-enhanced MRI (CeMRI) with the most widely used imaging techniques for myocardial infarct (MI) diagnosis, SPECT and Echo, in unselected patients with chronic coronary artery disease (CAD). Two blinded operators assessed scars on MRI, SPECT and Echo images using a 16-segments LV model. We studied 105 consecutive patients: 50 had Q-wave MI (Q-MI), 19 non Q-wave MI or rest angina (nonQ-MI/RA) and 36 effort angina (EA) history. CeMRI was positive, respectively, in 96%, 37%, and 6%, SPECT in 90%, 53%, and 44%, and Echo in 84%, 32%, and 28% of patients (within Q-MI: CeMRI vs. SPECT p < 0.03, vs. Echo p < 0.001; within EA CeMRI vs. SPECT and ECHO p < 0.001; all trends p < 0.001, pseudo r-square: 0.56-0.75 for CeMRI, 0.18-0.28 for SPECT and 0.23-0.37 for Echo). CeMRI and SPECT agreed in 83 patients (79%); negative SPECT with 1 +/- 0 segments subendocardial delayed enhancement (DE) was found in 4 (4%); negative CeMRI with 4 +/- 3 segments perfusion defects in 18 (17%), 16 of whom were obese or showed LBB or sub-occlusion of related coronary. CeMRI and Echo agreed in 78 patients (75%); negative Echo with 2 +/- 1 segments subendocardial DE was found in 13 (12%) and negative CeMRI with 11 +/- 7 segments kinetic abnormalities in 14 (13%), in 10 confirmed by Cine-MRI. In Q-MI, CeMRI detects DE more frequently than perfusion defects and, especially, kinetic abnormalities are found by SPECT and Echo, respectively. CeMRI identifies small areas of DE also in some patients with nonQ-MI or RA but usually not in patients with EA. This biologically plausible decreasing trend is shown by CeMRI more clearly than by SPECT and Echo. Disagreement between CeMRI and SPECT or Echo may be reduced, but perhaps not fully eluded, performing dobutamine Echo and SPECT after maximal epicardial coronary dilatation. PMID:16136853

Catalano, Oronzo; Moro, Guido; Cannizzaro, Giorgio; Mingrone, Renato; Opasich, Cristina; Perotti, Mariarosa; Rognone, Felice; Frascaroli, Mauro; Baldi, Maurizia; Tramarin, Roberto

2005-01-01

234

Early-Onset Osteoarthritis, Charcot-Marie-Tooth Like Neuropathy, Autoimmune Features, Multiple Arterial Aneurysms and Dissections: An Unrecognized and Life Threatening Condition  

PubMed Central

Background Severe osteoarthritis and thoracic aortic aneurysms have recently been associated with mutations in the SMAD3 gene, but the full clinical spectrum is incompletely defined. Methods All SMAD3 gene mutation carriers coming to our centre and their families were investigated prospectively with a structured panel including standardized clinical workup, blood tests, total body computed tomography, joint X-rays. Electroneuromyography was performed in selected cases. Results Thirty-four SMAD3 gene mutation carriers coming to our centre were identified and 16 relatives were considered affected because of aortic surgery or sudden death (total 50 subjects). Aortic disease was present in 72%, complicated with aortic dissection, surgery or sudden death in 56% at a mean age of 45 years. Aneurysm or tortuosity of the neck arteries was present in 78%, other arteries were affected in 44%, including dissection of coronary artery. Overall, 95% of mutation carriers displayed either aortic or extra-aortic arterial disease. Acrocyanosis was also present in the majority of patients. Osteoarticular manifestations were recorded in all patients. Joint involvement could be severe requiring surgery in young patients, of unusual localization such as tarsus or shoulder, or mimicking crystalline arthropathy with fibrocartilage calcifications. Sixty eight percent of patients displayed neurological symptoms, and 9 suffered peripheral neuropathy. Electroneuromyography revealed an axonal motor and sensory neuropathy in 3 different families, very evocative of type II Charcot-Marie-Tooth (CMT2) disease, although none had mutations in the known CMT2 genes. Autoimmune features including Sjogren’s disease, rheumatoid arthritis, Hashimoto’s disease, or isolated autoantibodies- were found in 36% of patients. Interpretation SMAD3 gene mutations are associated with aortic dilatation and osteoarthritis, but also autoimmunity and peripheral neuropathy which mimics type II Charcot-Marie-Tooth. PMID:24804794

Aubart, Mélodie; Gobert, Delphine; Aubart-Cohen, Fleur; Detaint, Delphine; Hanna, Nadine; d’Indya, Hyacintha; Lequintrec, Janine-Sophie; Renard, Philippe; Vigneron, Anne-Marie; Dieudé, Philippe; Laissy, Jean-Pierre; Koch, Pierre; Muti, Christine; Roume, Joelle; Cusin, Veronica; Grandchamp, Bernard; Gouya, Laurent; LeGuern, Eric; Papo, Thomas; Boileau, Catherine; Jondeau, Guillaume

2014-01-01

235

Late Rather Than Early Onset Bubbles in the Pulmonary Artery During Altitude Exposures Correlate Better with the Onset of "Pain-Only" Decompression Illness  

NASA Technical Reports Server (NTRS)

Mechanistic insight about "pain-only" decompression illness (DCI) is limited given indirect information about venous gas emboli (VGE) detected in the pulmonary artery with Doppler ultrasound. However, we show that VGE first detected late in an altitude exposure are closely associated with subsequent symptom onset. Knowing that VGE occur late is an indication that a symptom will occur soon, but this is not a sufficient condition to guarantee that a symptom will occur.

Conkin, J.; Gernhardt, M. L.; Powell, M. R.

2005-01-01

236

Attentional enhancement via selection and pooling of early sensory responses in human visual cortex  

PubMed Central

Summary To characterize the computational processes by which attention improves behavioral performance, we measured activity in visual cortex with functional magnetic resonance imaging as humans performed a contrast-discrimination task with focal and distributed attention. Focal attention yielded robust improvements in behavioral performance that were accompanied by increases in cortical responses. Using a quantitative analysis, we determined that if performance were limited only by the sensitivity of the measured sensory signals, the improvements in behavioral performance would have corresponded to an unrealistically large (approximately 400%) reduction in response variability. Instead, behavioral performance was well characterized by a pooling and selection process for which the largest sensory responses, those most strongly modulated by attention, dominated the perceptual decision. This characterization predicts that high contrast distracters that evoke large sensory responses should have a negative impact on behavioral performance. We tested and confirmed this prediction. We conclude that attention enhanced behavioral performance predominantly by enabling efficient selection of the behaviorally relevant sensory signals. PMID:22153378

Pestilli, Franco; Carrasco, Marisa; Heeger, David J.; Gardner, Justin L.

2011-01-01

237

Bone structure and strength are enhanced in rats programmed by early overfeeding.  

PubMed

Childhood obesity is growing in prevalence. Obesity and bone dysfunctions may be related disorders, and therefore our aim was to study the impact of the early overfeeding (EO) in offspring bone health since weaning up to adulthood. To induce EO during lactation, litter size was adjusted to 3 male rats per litter (SL). Litter containing 10 pups per mother was the control (NL). Bone tissue was evaluated by dual-energy X-ray absorptiometry, computed tomography, microcomputed tomography, biomechanical tests, and serum analyses. SL offspring presented higher body weight, fat mass, lean mass from 21 up to 180 days, hyperphagia, and higher visceral fat mass. Bone analysis showed that SL offspring presented higher total bone mineral density (BMD) only at 180 days, and higher total bone mineral content and higher bone area from 21 until 180 days. At 180 days, SL offspring presented higher femur BMD and fourth lumbar vertebra (LV4) BMD, higher femoral head radiodensity and LV4 vertebral body radiodensity, lower trabecular pattern factor and trabecular separation, however with higher trabecular number, higher maximal load, resilience, stiffness and break load, and lower break deformation. SL group had, at 180 days, higher osteocalcin and lower C-terminal cross-linked telopeptide of type I collagen (CTX I). We have shown that the excess of fat mass contributed to an increased bone mass, and hypothesized that this increase could be mediated by the hypothyroidism and previous higher thyroid hormone action and hyperleptinemia at weaning. Furthermore, the increased biomechanical loading due to increased body weight probably help us to understand the protective effects obesity exerts upon bone health. PMID:24627101

de Albuquerque Maia, L; Lisboa, P C; de Oliveira, E; da Conceição, E P S; Lima, I C B; Lopes, R T; Ruffoni, L D G; Nonaka, K O; de Moura, E G

2014-04-01

238

A model-constrained Monte Carlo method for blind arterial input function estimation in dynamic contrast-enhanced MRI: II. In vivo results  

NASA Astrophysics Data System (ADS)

Accurate quantification of pharmacokinetic model parameters in tracer kinetic imaging experiments requires correspondingly accurate determination of the arterial input function (AIF). Despite significant effort expended on methods of directly measuring patient-specific AIFs in modalities as diverse as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), dynamic positron emission tomography (PET), and perfusion computed tomography (CT), fundamental and technical difficulties have made consistent and reliable achievement of that goal elusive. Here, we validate a new algorithm for AIF determination, the Monte Carlo blind estimation (MCBE) method (which is described in detail and characterized by extensive simulations in a companion paper), by comparing AIFs measured in DCE-MRI studies of eight brain tumor patients with results of blind estimation. Blind AIFs calculated with the MCBE method using a pool of concentration-time curves from a region of normal brain tissue were found to be quite similar to the measured AIFs, with statistically significant decreases in fit residuals observed in six of eight patients. Biases between the blind and measured pharmacokinetic parameters were the dominant source of error. Averaged over all eight patients, the mean biases were +7% in K trans, 0% in kep, -11% in vp and +10% in ve. Corresponding uncertainties (median absolute deviation from the best fit line) were 0.0043?min-1 in K trans, 0.0491 min-1 in kep, 0.29% in vp and 0.45% in ve. The use of a published population-averaged AIF resulted in larger mean biases in three of the four parameters (-23% in K trans, -22% in kep, -63% in vp), with the bias in ve unchanged, and led to larger uncertainties in all four parameters (0.0083 min-1 in K trans, 0.1038 min-1 in kep, 0.31% in vp and 0.95% in ve). When blind AIFs were calculated from a region of tumor tissue, statistically significant decreases in fit residuals were observed in all eight patients despite larger deviations of these blind AIFs from the measured AIFs. The observed decrease in root-mean-square fit residuals between the normal brain and tumor tissue blind AIFs suggests that the local blood supply in tumors is measurably different from that in normal brain tissue and that the proposed method is able to discriminate between the two. We have shown the feasibility of applying the MCBE algorithm to DCE-MRI data acquired in brain, finding generally good agreement with measured AIFs and decreased biases and uncertainties relative to the use of a population-averaged AIF. These results demonstrate that the MCBE algorithm is a useful alternative to direct AIF measurement in cases where acquisition of high-quality arterial input function data is difficult or impossible.

Schabel, Matthias C.; DiBella, Edward V. R.; Jensen, Randy L.; Salzman, Karen L.

2010-08-01

239

Hepatic Arterial Phase on Gadoxetic Acid-Enhanced Liver MR Imaging: A Randomized Comparison of 0.5 mL/s and 1 mL/s Injection Rates  

PubMed Central

Objective To compare gadoxetic acid injection rates of 0.5 mL/s and 1 mL/s for hepatic arterial-phase magnetic resonance (MR) imaging. Materials and Methods In this prospective study, 101 consecutive patients with suspected focal liver lesions were included and randomly divided into two groups. Each group underwent dynamic liver MR imaging using a 3.0-T scanner after an intravenous injection of gadoxetic acid at rates of either 0.5 mL/s (n = 50) or 1 mL/s (n = 51). Arterial phase images were analyzed after blinding the injection rates. The signal-to-noise ratios (SNRs) of the liver, aorta, portal vein, hepatic vein, spleen, and pancreas were measured. The contrast-to-noise ratios (CNRs) of the hepatocellular carcinomas (HCC) were calculated. Finally, two experienced radiologists were independently asked to identify, if any, HCCs in the liver on the images and score the image quality in terms of the presence of artifacts and the proper enhancement of the liver, aorta, portal vein, hepatic vein, hepatic artery, spleen, pancreas, and kidney. Results The SNRs were not significantly different between the groups (p = 0.233-0.965). The CNRs of the HCCs were not significantly different (p = 0.597). The sensitivity for HCC detection and the image quality scores were not significantly different between the two injection rates (p = 0.082-1.000). Conclusion Image quality and sensitivity for hepatic HCCs of arterial-phase gadoxetic acid-enhanced MR were not significantly improved by reducing the contrast injection rate to 0.5 mL/s compared with 1 mL/s. PMID:25246821

Kim, Sung Mo; Heo, Suk Hee; Kim, Jin Woong; Lim, Hyo Soon; Shin, Sang Soo; Kang, Heoung Keun

2014-01-01

240

Arterial endothelial function measurement method and apparatus  

DOEpatents

A "relaxoscope" (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxation. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.

Maltz, Jonathan S; Budinger, Thomas F

2014-03-04

241

Early Cardioprotective Effect of Sevoflurane on Left Ventricular Performance during Coronary Artery Bypass Grafting on a Beating Heart: Randomized Controlled Study  

PubMed Central

Aim To evaluate the cardioprotective effect of sevoflurane on a beating heart in patients undergoing coronary artery bypass grafting with normal preoperative left ventricular function. Methods The randomized controlled study included 32 patients induced with sevoflurane and then randomized to receive either 1 minimal alveolar concentration (MAC) end-tidal concentration of sevoflurane (n?=?16) or propofol (n?=?16) 2 to 3 mg kg-1 hour-1. The acceleration of the aortic blood flow, cardiac index, heart rate, mean arterial pressure, and central venous pressure were measured 5 minutes after anesthesia induction, at the beginning of ischemia, 15 minutes after ischemia, and 15 minutes after sternum closure. Results There were no differences in heart rate, mean arterial pressure, and central venous pressure within each group and between groups during surgery. Acceleration increased in the sevoflurane group 15 minutes after ischemia (10.3?±?3.5 m/s2; P?=?0.004) and 15 minutes after sternum closure (10.7?±?3.9 m/s2; P<0.001). Acceleration in the propofol group decreased from the beginning of ischemia (P<0.001) and remained lower 15 minutes after sternum closure (P?=?0.001 and P?=?0.024, respectively). Acceleration was higher in the sevoflurane group at the beginning of ischemia and 15 minutes after sternum closure (P?=?0.017 and P?=?0.046, respectively). There were no significant differences in cardiac index values within the sevoflurane group. In the propofol group, significant decreases in cardiac index were seen at the beginning of ischemia (P<0.001). There were between-group differences in cardiac index values at the beginning of ischemia and 15 minutes after ischemia (P?=?0.002, and P?=?0.011, respectively). Conclusion Cardiac function was better preserved in the patients anesthetized with sevoflurane than in patients anesthetized with propofol. Trial Registration ClinicalTrials.gov Identifier NCT00477737 PMID:17589976

Husedžinovi?, Ino; Barišin, Stjepan; Bradi?, Nikola; Milanovi?, Rudolf

2007-01-01

242

Outcome of pediatric liver transplant in grafts with multiple arteries.  

PubMed

Young age, small diameter of the hepatic artery, presence of multiple arteries, and the selected technique are risk factors for hepatic arterial complications. We report the outcomes of pediatric liver transplant (LT) patients who had received a liver graft with multiple arteries. Since April 2001, 89 pediatric LTs have been performed at our center. Twenty-six liver grafts (29.2%) that had multiple hepatic arteries were analyzed retrospectively. Twenty-five grafts had 2, and 1 graft had 3, hepatic arteries. In 17 grafts with double arteries, and in 1 graft with 3 arteries, the adjacent edges of the hepatic arteries were sutured together at the back table to create a single opening, and the recipient's common hepatic artery was then anastomosed to that orifice. In 8 grafts with double arteries, 2 separate anastomoses were performed between the graft hepatic arteries and the recipient's hepatic artery branches. The mean age of the recipients was 7.9 +/- 5.4 years (range, 0.6-17 years). During the early postoperative period, hepatic arterial thromboses occurred in 3 recipients. Two of these 3 recipients were treated with transcatheter arterial thrombolysis using streptokinase or recombinant plasminogen and intraluminal stent placement, and the remaining recipient was treated with a re-anastomosis using a polytetrafluoroethylene graft. Three recipients died during follow-up, which ranged from 1 to 71 months. In conclusion, multiple graft arteries did not increase the incidence of hepatic arterial complications in our series. PMID:18266797

Haberal, Mehmet; Sevmis, Sinasi; Karakayali, Hamdi; Moray, Gokhan; Ozcay, Figen; Torgay, Adnan; Arslan, Gulnaz

2008-06-01

243

In vivo evaluation of retinal and callosal projections in early postnatal development and plasticity using manganese-enhanced MRI and diffusion tensor imaging  

Microsoft Academic Search

The rodents are an excellent model for understanding the development and plasticity of the visual system. In this study, we explored the feasibility of Mn-enhanced MRI (MEMRI) and diffusion tensor imaging (DTI) at 7T for in vivo and longitudinal assessments of the retinal and callosal pathways in normal neonatal rodent brains and after early postnatal visual impairments. Along the retinal

Kevin C. Chan; Joe S. Cheng; Shujuan Fan; Iris Y. Zhou; Jian Yang; Ed X. Wu

244

Location of foot arteries using infrared images  

NASA Astrophysics Data System (ADS)

In this work are presented the results of localization of foot arteries, in a young group of participants by using infrared thermal images, these are the dorsal, posterior tibial and anterior tibial arteries. No inclusion criteria were considered, that causes that no strong statistical data about the influence of the age in the arterial localization. It was achieved to solve the confusion when veins present a heat distribution similar to the artery and in the position of this. it contributes to enhance the rate of location of arteries. In general it is possible to say that the use of infrared thermal images is a good technique to find the foot arteries and can be applied in its characterization in a future. The procedure proposed is a non-invasive technique, and in certain fashion does not requires specialized personnel to achieve locate the arteries. It is portable, safe, and relatively economical.

Villasenor-Mora, Carlos; González-Vega, Arturo; Martín Osmany Falcón, Antonio; Benítez Ferro, Jesús Francisco Guillemo; Córdova Fraga, Teodoro

2014-11-01

245

Proinflammation: The Key to Arterial Aging  

PubMed Central

Arterial aging is the major contributing factor to increases in the incidence and prevalence of cardiovascular disease, due mainly to the presence of chronic, low-grade, “sterile” arterial inflammation. Inflammatory signaling driven by the angiotensin II cascade perpetrates adverse age-associated arterial structural and functional remodeling. The aged artery is characterized by endothelial disruption, enhanced vascular smooth muscle cell migration and proliferation, extracellular matrix deposition, elastin fracture, and matrix calcification/amyloidosis/glycation. Importantly, the molecular mechanisms of arterial aging are also relevant to the pathogenesis of hypertension, and atherosclerosis. Age-associated arterial proinflammation is, to some extent, mutable, and interventions to suppress or delay it may have the potential to ameliorate or retard age-associated arterial diseases. PMID:24365513

Wang, Mingyi; Jiang, Liqun; Monticone, Robert E.; Lakatta, Edward G.

2014-01-01

246

Coronary Artery Bypass Grafting  

MedlinePLUS

... from the NHLBI on Twitter. What Is Coronary Artery Bypass Grafting? Coronary artery bypass grafting (CABG) is ... bypass multiple coronary arteries during one surgery. Coronary Artery Bypass Grafting Figure A shows the location of ...

247

Peripheral Artery Disease  

MedlinePLUS

Peripheral Artery Disease • Overview Peripheral artery disease, or P.A.D., refers to arterial disease that occurs outside of the heart or brain. In P.A.D., the arteries that carry oxygenated blood throughout the body become ...

248

May 2012 Arterial  

E-print Network

May 2012 Arterial Transitway Corridors Study: Results and Conclusions about Arterial Bus Rapid Transit #12;Arterial Transitway Corridors Study of "Arterial BRT" concept from Met Council TPP ­ Concept/feasibility study led by Metro

Minnesota, University of

249

Carotid artery surgery  

MedlinePLUS

... A flexible tube (catheter) is put in the artery. Blood flows through the catheter around the blocked area ... the artery. After the plaque is removed, the artery is closed with stitches. Blood now flows through the artery to your brain. ...

250

Early molecular imaging of interstitial changes in patients after myocardial infarction: Comparison with delayed contrast-enhanced magnetic resonance imaging  

PubMed Central

Introduction The clinical feasibility of noninvasive imaging of interstitial alterations after myocardial infarction (MI) was assessed using a technetium-99m-labeled RGD imaging peptide (RIP). In experimental studies, RIP has been shown to target integrins associated with collagen-producing myofibroblasts (MFB). Methods and Results Ten patients underwent myocardial perfusion imaging (MPI) within the first week after MI. At 3 and 8 weeks after MI, RIP was administered intravenously and SPECT images acquired for interstitial imaging. RIP imaging was compared to initial MPI and to the extent of scar formation defined by late gadolinium-enhanced (LGE) cardiac magnetic resonance (CMR) imaging 1 year after MI. RIP uptake was observed in 7 of the 10 patients at both 3 and 8 weeks. Although, RIP uptake corresponded to areas of perfusion defects, it usually extended beyond the infarct zone to a variable extent; 2 of 7 patients showed tracer uptake throughout myocardium. In all positive cases, RIP uptake was similar to the extent of scar observed at 1 year by LGE-CMR imaging. Conclusion This study demonstrates that RGD-based imaging early after MI may predict the eventual extent of scar formation, which often exceeds initial MPI deficit but colocalizes with LGE in CMR imaging performed subsequently. PMID:20658273

Verjans, Johan; Wolters, Sander; Laufer, Ward; Schellings, Mark; Lax, Michelle; Lovhaug, Dagfinn; Boersma, Hendrikus; Kemerink, Gerrit; Schalla, Simon; Gordon, Paul; Teule, Jaap

2010-01-01

251

Gallium-67 uptake in the lung of asbestos exposed sheep: early association with enhanced macrophage-derived fibronectin accumulation  

SciTech Connect

To evaluate the time course and mechanisms of enhanced /sup 67/Ga lung uptake in asbestosis, we exposed two groups of sheep every 2 wk to either 100 ml saline (controls) or 100 mg UICC chrysotile fibers in 100 ml saline. The sheep were evaluated periodically by pulmonary function tests (PFT), thoracic radiograph (TR), /sup 67/Ga lung scan, bronchoalveolar lavage (BAL), and transbronchial lung biopsy (TLB). By month 24 of the study, 9/15 exposed sheep had developed the initial alveolitis and had significant changes in PFT, TR, and TLB. The other six exposed sheep differed from controls only by a 75% increase in BAL fibronectin until month 30, where significant changes in albumin occurred and /sup 67/Ga scan score increased. The nine sheep with alveolitis had significant sustained increases in /sup 67/Ga scan and BAL levels from month 6, associated with a 150% increase in BAL fibronectin and other parameters of disease activity changed from month 18 to 30. We concluded that in the sheep model of asbestosis, significant changes in /sup 67/Ga scan, /sup 67/Ga BAL counts, and excessive elevation of BAL fibronectin preceded other parameters of disease activity. The data suggest that excessively activated macrophages are primarily responsible for the early /sup 67/Ga lung uptake.

Begin, R.; Bisson, G.; Lambert, R.; Cote, Y.; Fabi, D.; Martel, M.; Lamoureux, G.; Rola-Pleszczynski, M.; Boctor, M.; Dalle, D.

1986-04-01

252

Feeding Artery of Laryngeal and Hypopharyngeal Cancers: Role of the Superior Thyroid Artery in Superselective Intraarterial Chemotherapy  

SciTech Connect

The purpose of this study was to elucidate the role of the superior thyroid artery in intra-arterial infusion chemotherapy for laryngeal and hypopharyngeal cancers. Thirty-nine patients with laryngeal cancer and 29 patients with hypopharyngeal cancer underwent intra-arterial infusion chemotherapy. We performed a retrospective analysis of the feeding arteries confirmed by computed tomography during selective arteriography and compared the results with the extent of the tumors. In 14 of 39 laryngeal and 15 of 29 hypopharyngeal cancers, the tumor did not cross the midline (group 1). In the remaining 25 and 14 cancers, respectively, the tumor crossed the midline or located in the center (group 2). For 13 of 14 laryngeal and 7 of 15 hypopharyngeal cancers in group 1 and for 6 of 25 laryngeal cancers in group 2, the entire tumor was contrast enhanced by the ipsilateral superior thyroid and/or superior laryngeal artery. For 12 of 25 laryngeal and 1 of 14 hypopharyngeal cancers in group 2, the entire tumor was contrast enhanced by the bilateral superior thyroid artery. For the other patients, infusion via the other arterial branches such as the inferior thyroid and the lingual arteries were needed to achieve contrast enhancement of the entire tumor. Superselective intra-arterial chemotherapy for laryngeal cancer from the superior thyroid artery is appropriate, whereas that for hypopharyngeal cancer is less sufficient. To accomplish contrast enhancement of the entire tumor, additional intra-arterial infusion from other arteries such as the inferior thyroid artery is often necessary.

Terayama, Noboru, E-mail: tera@rad.m.kanazawa-u.ac.jp; Sanada, Junichiro; Matsui, Osamu; Kobayashi, Satoshi; Kawashima, Hiroko; Yamashiro, Masashi; Takanaka, Tsuyoshi; Kumano, Tomoyasu; Yoshizaki, Tomokazu [Kanazawa University Graduate School of Medical Science, Department of Radiology (Japan); Furukawa, Mitsuru [Kanazawa University Graduate School of Medical Science, Department of Otorhinolaryngology (Japan)

2006-08-15

253

Enhance  

NSDL National Science Digital Library

It doesn't take a Photoshop expert to create attractive graphics for the Web. To prove this, the folks at MicroFrontier have released three graphic creation/editing packages for the Macintosh, each aimed at a different user level. All three applications support Photoshop 3.0 compatible plug-ins and basic features such as scanner support, image and resolution scaling, and basic image enhancement. Enhance, aimed at the graphics professionals, adds even more features, including multiple layers, opacity control, sixteen levels of undo, convolution filter effects, and CYMK support. A save-disabled demo version of each application is available at the MicroFrontier Website. The price for Enhance is $100 .

1998-01-01

254

Preradiotherapy Calcium Scores of the Coronary Arteries in a Cohort of Women With Early-Stage Breast Cancer: A Comparison With a Cohort of Healthy Women  

SciTech Connect

Purpose: Breast cancer radiotherapy has been associated with an increased risk of cardiac toxicity. However, no data are available on the probability of developing coronary artery disease (CAD) in breast cancer patients when compared with healthy women. Therefore, baseline coronary artery calcium (CAC) scores, as an accepted tool to predict CAD, were determined and compared with the CAC scores of a healthy, asymptomatic cohort, the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Methods and Materials: Eighty consecutive patients with ductal carcinoma in situ or infiltrative breast cancer referred for radiotherapy after breast-conserving surgery were included in our study. Their cardiovascular risk profile was registered, and a 64 multislice CT scan was performed. The CAC scores of an unselected (Caucasian only) Radiotherapy Centre West (RCWEST) cohort, as well as of those of a selected (comorbidity and race adjusted) RCWEST cohort, were determined. The scores of both cohorts were compared with those of the female (Caucasian only) MESA cohort. Results: For the unselected RCWEST cohort (n = 62) we found significant (p < .01) higher scores for women in the 55-64 age category compared with those of the MESA cohort. In the selected cohort (n = 55) the CAC scores of the women in the age category 55-64 were significantly (p = .02) higher compared with the MESA cohort. No significant differences were noted in the other age categories. Conclusion: Both cohorts revealed that CAC scores in the 55-64 age category were significantly higher than the CAC scores in the asymptomatic (female) MESA population. These data suggest that breast cancer patients bear a higher risk of developing coronary heart disease before the start of radiotherapy. Therefore, measures to decrease cardiac dose further in breast cancer radiotherapy are even more important.

Mast, Mirjam E., E-mail: m.mast@mchaaglanden.nl [Radiotherapy Centre West, The Hague (Netherlands); Heijenbrok, Mark W. [Department of Radiology, Medical Center Haaglanden, The Hague (Netherlands); Petoukhova, Anna L. [Radiotherapy Centre West, The Hague (Netherlands); Scholten, Astrid N. [Department of Clinical Oncology, Leiden University Medical Centre, Leiden (Netherlands); Schreur, Joop H.M. [Department of Cardiology, Medical Center Haaglanden, The Hague (Netherlands); Struikmans, Henk [Radiotherapy Centre West, The Hague (Netherlands); Department of Clinical Oncology, Leiden University Medical Centre, Leiden (Netherlands)

2012-07-01

255

Neurofibromatosis type 1 and multiple traumatic cervical arterial injuries: a case report  

PubMed Central

Introduction Blunt injury to the carotid and vertebral arteries is uncommon and potentially devastating. Neurofibromatosis type 1, or von Recklinghausen’s disease is an autosomal dominant disorder affecting one in 3000 individuals. This genetic disease may affect many organs, including vessels. Case presentation This report describes a very unusual case of multiple traumatic arterial injuries in a 44-year-old Caucasian neurofibromatosis type 1 patient, with delayed diagnosis. The vascular abnormalities observed in neurofibromatosis type 1, probably enhanced the arterial lesions. Medical treatment with antiplatelet therapy combined with endovascular stent-assisted angioplasty allowed a good evolution for the patient. Conclusion Patients with medical history of neurofibromatosis type I are at risk to develop blunt cervical vascular injury. This association has to be known by emergency and intensivist physicians to optimize screening of cerebrovascular injuries and treat early such devastating lesions. PMID:19918515

Chevalier, Stéphanie; Jehan, Claude; Courtheoux, Patrick; Gérard, Jean-Louis; Hanouz, Jean-Luc; Plaud, Benoit

2009-01-01

256

Echocardiographic determination of mean pulmonary artery pressure  

Microsoft Academic Search

We performed a simultaneous Doppler and invasive study to validate the role of Doppler-derived peak pulmonary regurgitant velocity as a reliable noninvasive measure of pulmonary artery mean pressure. Assessment of right atrial pressure, as shown in this study, enhances the use of this Doppler parameter as a correlate of pulmonary artery mean pressure.

Amr E. Abbas; F. David Fortuin; Nelson B. Schiller; Christopher P. Appleton; Carlos A. Moreno; Steven J. Lester

2003-01-01

257

Science Education in Early Childhood Teacher Education: Putting Forward a Case to Enhance Student Teachers' Confidence and Competence  

Microsoft Academic Search

New Zealand is moving towards increased qualification requirements for early childhood educators. There is an underlying assumption that there is a correlation between quality early childhood education, teacher qualifications and quality practices in teaching and learning. Two fields of literature, early childhood pedagogy and science specific pedagogy, are reviewed briefly to provide a framework with which to consider why student

Dawn Garbett

2003-01-01

258

Arterial embolism  

MedlinePLUS

... arm or leg. There may be signs of tissue death or gangrene. Tests to diagnose arterial embolism or reveal the source of emboli may include: Angiography of the affected extremity or organ Doppler ultrasound exam of an extremity Duplex Doppler ultrasound ...

259

Early-Stage Investigations of Ultrasmall Superparamagnetic Iron Oxide-Induced Signal Change After Permanent Middle Cerebral Artery Occlusion in Mice  

Microsoft Academic Search

Background and Purpose—MR signal changes after intravenous ultrasmall superparamagnetic iron oxide (USPIO) injection are related to inflammatory cells at the subacute stages after focal cerebral injury. However, at the early stages, the interpretation of USPIO-related MR signal alterations remains controversial. Here, we compared MR signal changes after intravenous USPIO injection with the histological iron and macrophage distribution during the first

Virginie Desestret; Jean-Christophe Brisset; Samir Moucharrafie; Emilie Devillard; Serge Nataf; Jerome Honnorat; Norbert Nighoghossian; Yves Berthezène; Marlene Wiart

2010-01-01

260

Popliteal Artery Pseudoaneurysm Following Primary Total Knee Arthroplasty  

PubMed Central

An early diagnosis of popliteal artery pseudoaneurysm-a sequela of popliteal artery trauma-is difficult owing to its late presentation following total knee arthroplasty. The incidence of a popliteal artery pseudoaneurysm with a hematoma presenting only a peripheral nerve injury after total knee arthroplasty is also uncommon in the absence of common diagnostic features such as a pulsatile swelling with an audible bruit on auscultation. In the present report, we describe popliteal artery pseudoaneurysm following total knee arthroplasty. PMID:24944978

Shin, Young-Soo; Hwang, Yeok-Gu; Savale, Abhijit Prakash

2014-01-01

261

Detection of early interproximal caries in vitro using laser fluorescence, dye-enhanced laser fluorescence and direct visual examination.  

PubMed

This in vitro study evaluated the use of laser fluorescence (LF) for the detection of early interproximal carious lesions and whether the detection could be enhanced using a fluorescent dye (DELF). Direct visual examination (DV) was used for comparison. Eighty extracted teeth were used, arranged in 20 blocks, each block having 2 premolars and 2 molars, lined up in a simulated sextant situation. After cleaning with a microabrasion kit, a subcontact window on half of the surfaces (60) was exposed to Carbopol white-spot solution for 5 days. The teeth were remounted in stone and examined by three independent examiners. For LF and DELF an argon laser was used (mixed wavelength of 488 and 514 nm) viewed through glasses (excluding wavelength <520 nm). For DELF a sodium fluorescein dye (0. 075%) was applied before examination. A clinical examination light was used for DV. The approximal surfaces were scored for lesion presence or absence. To verify lesion presence, the subcontact area was cut perpendicularly to the surface, stained with rhodamine B, and images were taken using a confocal microscope. The images were analyzed using a histogram program for lesion depth and image area. Lesions were present in 62 out of 120 approximal surfaces, with an average depth of 60 microm (range 17-190 microm). Sensitivity ranges for LF, DELF and DV were 56-74, 61-79 and 58-74%, and specificity ranges 67-78, 86-98 and 83-97%, respectively. With this model DELF compared favorably with DV and LF in sensitivity, but specificity was better for DELF and DV than for LF. PMID:10207199

Eggertsson, H; Analoui, M; van der Veen, M; González-Cabezas, C; Eckert, G; Stookey, G

1999-01-01

262

Remission of High Blood Pressure Reverses Arterial Potassium Channel Alterations  

Microsoft Academic Search

Rat arterial muscle cells show an elevated Ca2+- dependent K+ efflux during the established phase of hyperten- sion. This association of enhanced K+ efflux with high arterial pressure implies that changes of in vivo blood pressure can alter the level of K+ channel current in arterial membranes. We directly tested this hypothesis by comparing K + current density between patch-clamped

Nancy J. Rusch; Anne M. Runnells

263

Early stage effect of ischemic preconditioning for patients undergoing on-pump coronary artery bypass grafts surgery: systematic review and meta-analysis  

PubMed Central

Background: During the on-pump coronary artery bypass grafts surgery, ischemia/reperfusion injury would happen. Ischemia preconditioning could increase the tolerance against subsequent ischemia and reduce the ischemia/reperfusion injury. However the clinical outcomes of the available trials were different. Methods : We searched the Cochrane Central Register of Controlled Trials on The Cochrane Library (Issue 3, 2013), the Medline/PubMed and CNKI in March 2013. RevMan 5.1.6 and GRADEprofiler 3.6 were used for statistical analysis and evidence quality assessment. Heterogeneity was evaluated with significance set at P?0.10. Results: Eighteen randomized controlled trials were included. There were no differences on in-hospital mortality, postoperative myocardial infarction morbidity between ischemia preconditioning and control groups. The heterogeneity of creatine kinase-MB level 24 hours after surgery was obvious. The differences of 72 hours area under the curve of cardiac troponin T (mean differences of -14.50, 95% confidence interval of -21.71 to -7.28) and troponin I (mean differences -181.79, 95% confidence interval of -270.07 to -93.52) after surgery were observed. Conclusion s : All the 18 trails, the positive and the negative results were equal. The meta-analysis results should be interpreted with caution due to limited effective data. Because of high cost-effectiveness, ischemia preconditioning could not be denied completely. Large-scale randomized studies are needed, with the operation procedures and included criteria being more specific. PMID:24948996

Chai, Qing; Liu, Jin

2014-01-01

264

Negative associations between arterial stiffness parameter evaluated by cardio-ankle vascular index and serum low-density lipoprotein cholesterol concentration in early-stage atherosclerosis.  

PubMed

The cardio-ankle vascular index (CAVI), calculated values from cardio-ankle pulse wave velocity and blood pressure, corresponds predominantly to the stiffness of the aorta and peripheral arteries of the lower limbs. However, the reported associations between CAVI and serum low-density lipoprotein cholesterol (LDL-C) levels remain inconsistent. A cross-sectional study of 1878 consecutive patients (mean age: 59.2 years) who underwent general health checkup showed a negative association between CAVI and serum LDL-C or non-high-density lipoprotein cholesterol (non-HDL-C) concentrations with age-adjusted correlation and multiple regression analysis. Using the similar analyses divided by the status of risk factors and degree of maximum carotid intima-media thickness (maxIMT), negative correlations between CAVI and LDL-C or non-HDL-C levels were observed only in nonrisk groups including nondiabetics patients or patients with maxIMT <1.0 mm, in those with expected low extent of advanced atherosclerotic lesions. In contrast, such a correlation was not found in each comparable risk-loaded group. PMID:24402322

Homma, Satoki; Kato, Kiyoe; Hayashi, Junichi; Yamamoto, Minoru

2015-02-01

265

Early Risk of Mortality after Coronary Artery Revascularization in Patients with Left Ventricular Dysfunction and Potential Role of the Wearable Cardioverter Defibrillator  

PubMed Central

Background Implantable cardioverter defibrillator (ICD) implantation for prevention of sudden cardiac death is typically deferred for 90 days after coronary revascularization, but mortality may be highest early after cardiac procedures in patients with ventricular dysfunction. We determined mortality risk in post-revascularization patients with left ventricular ejection fraction (LVEF) ?35% and compared survival to those discharged with a wearable cardioverter defibrillator (WCD). Methods and Results Hospital survivors after surgical (CABG) or percutaneous (PCI) revascularization with LVEF?35% were included from Cleveland Clinic and national WCD registries. Kaplan-Meier, Cox proportional hazards, propensity score-matched survival and hazard function analyses were performed. Early mortality hazard was higher among 4149 patients discharged without a defibrillator compared to 809 with WCDs (90-day mortality post-CABG 7% vs. 3%, p=0.03; post-PCI 10% vs. 2%, p<0.0001). WCD use was associated with adjusted lower risks of long-term mortality in the total cohort (39%, p<0.0001) and both post-CABG (38%, p=0.048) and post-PCI (57%, p<0.0001) cohorts (mean follow-up 3.2 years). In propensity-matched analyses, WCD use remained associated with lower mortality (58% post-CABG, p=0.002; 67% post-PCI, p<0.0001). Mortality differences were not attributable solely to therapies for ventricular arrhythmia. Only 1.3% of the WCD group had a documented appropriate therapy. Conclusions Patients with LVEF?35% have higher early compared to late mortality after coronary revascularization, particularly after PCI. As early hazard appeared less marked in WCD users, prospective studies in this high risk population are indicated to confirm whether WCD use as a bridge to LVEF improvement or ICD implantation can improve outcomes after coronary revascularization. PMID:23275233

Zishiri, Edwin T.; Williams, Sarah; Cronin, Edmond M.; Blackstone, Eugene H.; Ellis, Stephen G.; Roselli, Eric E.; Smedira, Nicholas G.; Gillinov, A. Marc; Glad, Jo Ann; Tchou, Patrick J.; Szymkiewicz, Steven J.; Chung, Mina K.

2013-01-01

266

Cerebral perfusion information obtained by dynamic contrast-enhanced phase-shift magnetic resonance imaging: comparison with model-free arterial spin labelling.  

PubMed

Phase-shift time curves following a bolus injection of gadolinium contrast agent were registered for grey-matter regions and large vessels in 14 subjects. Deconvolving a tissue phase-shift curve with a phase-based arterial input function resulted in a tissue residue function R(t). The peak value of R(t) provided a relative cerebral blood flow (CBF) index, while the area-to-height ratio of R(t) provided quantitative mean transit time (MTT). For comparison, quantitative CBF values in grey matter were acquired using model-free arterial spin labelling (ASL). The phase-based relative CBF estimates showed good linear correlation with ASL-based CBF (r = 0.82). Grey-matter MTT was 4.9 +/- 1.1 s (mean +/- SD). PMID:20618360

Wirestam, Ronnie; Lindgren, Emelie; van Westen, Danielle; Bloch, Karin Markenroth; Ståhlberg, Freddy; Knutsson, Linda

2010-09-01

267

Enhancement of ACNU treatment of the BT 4an rat glioma by local brain hyperthermia and intra-arterial drug administration  

Microsoft Academic Search

To evaluate the role of intra-arterial (i.a.) chemotherapy, intravenous (i.V.) chemotherapy, and local brain hyperthermia in the treattment of gliomas, the effect of i.v. versus i.a. drug delivery, with or without local brain hyperthermia, was evaluated in BD IX rats with BT4An gliomas implanted in the right frontal lobe. The rats were given ACNU 18 mg\\/kg i.a. in the right

B.-C. Schem; B. K. Krossnes

1995-01-01

268

Coronary arteries  

Microsoft Academic Search

.   Coronary angiography (CA) is presently considered the gold standard for the assessment of the coronary arteries. However,\\u000a the presence of ionizing radiation, its invasiveness and the small associated risk of morbidity prompted long ago the development\\u000a of more patient-friendly imaging modalities. A promising technique, magnetic resonance imaging (MRI), has been regarded as\\u000a the major modality in the coming decade.

P. A. Wielopolski; R. J. M. van Geuns; P. J. de Feyter; M. Oudkerk

2000-01-01

269

Nitrate reductase-mediated early nitric oxide burst alleviates oxidative damage induced by aluminum through enhancement of antioxidant defenses in roots of wheat (Triticum aestivum).  

PubMed

• Nitric oxide (NO) is an important signaling molecule involved in the physiological processes of plants. The role of NO release in the tolerance strategies of roots of wheat (Triticum aestivum) under aluminum (Al) stress was investigated using two genotypes with different Al resistances. • An early NO burst at 3 h was observed in the root tips of the Al-tolerant genotype Jian-864, whereas the Al-sensitive genotype Yang-5 showed no NO accumulation at 3 h but an extremely high NO concentration after 12 h. Stimulating NO production at 3 h in the root tips of Yang-5 with the NO donor relieved Al-induced root inhibition and callose production, as well as oxidative damage and ROS accumulation, while elimination of the early NO burst by NO scavenger aggravated root inhibition in Jian-864. • Synthesis of early NO in roots of Jian-864 was mediated through nitrate reductase (NR) but not through NO synthase. Elevated antioxidant enzyme activities were induced by Al stress in both wheat genotypes and significantly enhanced by NO donor, but suppressed by NO scavenger or NR inhibitor. • These results suggest that an NR-mediated early NO burst plays an important role in Al resistance of wheat through modulating enhanced antioxidant defense to adapt to Al stress. PMID:24237306

Sun, Chengliang; Lu, Lingli; Liu, Lijuan; Liu, Wenjing; Yu, Yan; Liu, Xiaoxia; Hu, Yan; Jin, Chongwei; Lin, Xianyong

2014-03-01

270

Influence of an Early Recovery Telehealth Intervention on Physical Activity and Functioning following Coronary Artery Bypass Surgery (CABS) among Older Adults with High Disease Burden  

PubMed Central

Background Older adults with poor functioning preoperatively are at risk for delayed recovery and more impaired outcomes following CABS. Purpose To determine if a 6-week early recovery telehealth intervention, designed to improve self-efficacy and management related to symptoms following CABS, was effective in improving outcomes (physical activity, physiological and psychological functioning) for older adults (> 65 years old) with higher disease burden. Design A descriptive, repeated measures experimental design was used. Follow-up data was collected at 3- and 6-weeks and 3-months after CABS. Sample Subjects were drawn from a larger randomized clinical trial (RCT). Parent study subjects who had high disease burden preoperatively [physical component score of <50 on the Medical Outcome Study Short Form 36 (MOS SF-36) and a RISKO score of > 6], were included (N=55); with 23 subjects in the early recovery intervention group and 31 subjects in the usual care group (n=31). Subjects ranged from 65–85 years old (M=71.6 + 5.1). Findings There was a significant main effect by group [F(1,209)=4.66, p<.05), the intervention group had a least square means of 27.9 kcal/kg/day of energy expenditure compared to the usual care group of 26.6 kcal/kg/day per the RT3® accelerometer. Both groups had significantly improved physical [F(2,171)=3.26, p<.05] and role-physical [F(2,171)=6.64, p<.005] functioning over time. Conclusions The subgroup of CABS subjects with high disease burden was responsive to an early recovery telehealth intervention. Improving patients’ physical activity and functioning can reduce morbidity and mortality associated with poor functioning after cardiac events. PMID:19944870

Barnason, Susan; Zimmerman, Lani; Schulz, Paula; Tu, Chunhao

2009-01-01

271

Widespread DNA hypomethylation at gene enhancer regions in placentas associated with early-onset pre-eclampsia  

PubMed Central

Pre-eclampsia is a serious complication of pregnancy that can affect both maternal and fetal outcomes. Early-onset pre-eclampsia (EOPET) is a severe form of pre-eclampsia that is associated with altered physiological characteristics and gene expression in the placenta. DNA methylation is a relatively stable epigenetic modification to DNA that can reflect gene expression, and can provide insight into the mechanisms underlying such expression changes. This case–control study focused on DNA methylation and gene expression of whole chorionic villi samples from 20 EOPET placentas and 20 gestational age-matched controls from pre-term births. DNA methylation was also assessed in placentas affected by late-onset pre-eclampsia (LOPET) and normotensive intrauterine growth restriction (nIUGR). The Illumina HumanMethylation450 BeadChip was used to assess DNA methylation at >480 000 cytosine-guanine dinucleotide (CpG) sites. The Illumina HT-12v4 Expression BeadChip was used to assess gene expression of >45 000 transcripts in a subset of cases and controls. DNA methylation analysis by pyrosequencing was used to follow-up the initial findings in four genes with a larger cohort of cases and controls, including nIUGR and LOPET placentas. Bioinformatic analysis was used to identify overrepresentation of gene ontology categories and transcription factor binding motifs. We identified 38 840 CpG sites with significant (false discovery rate <0.01) DNA methylation alterations in EOPET, of which 282 had >12.5% methylation difference compared with the controls. Significant sites were enriched at the enhancers and low CpG density regions of the associated genes and the majority (74.5%) of these sites were hypomethylated in EOPET. EOPET, but not associated clinical features, such as intrauterine growth restriction (IUGR), presented a distinct DNA methylation profile. CpG sites from four genes relevant to pre-eclampsia (INHBA, BHLHE40, SLC2A1 and ADAM12) showed different extent of changes in LOPET and nIUGR. Genome-wide expression in a subset of samples showed that some of the gene expression changes were negatively correlated with DNA methylation changes, particularly for genes that are responsible for angiogenesis (such as EPAS1 and FLT1). Results could be confounded by altered cell populations in abnormal placentas. Larger sample sizes are needed to fully address the possibility of sub-profiles of methylation within the EOPET cohort. Based on DNA methylation profiling, we conclude that there are widespread DNA methylation alterations in EOPET that may be associated with changes in placental function. This property may provide a useful tool for early screening of such placentas. This study identifies DNA methylation changes at many loci previously reported to have altered gene expression in EOPET placentas, as well as in novel biologically relevant genes we confirmed to be differentially expressed. These results may be useful for DNA- methylation-based non-invasive prenatal diagnosis of at-risk pregnancies. PMID:23770704

Blair, John D.; Yuen, Ryan K.C.; Lim, Brendan K.; McFadden, Deborah E.; von Dadelszen, Peter; Robinson, Wendy P.

2013-01-01

272

Air atmospheric-pressure plasma-jet treatment enhances the attachment of human gingival fibroblasts for early peri-implant soft tissue seals on titanium dental implant abutments.  

PubMed

Abstract Objective. Although dental implants are commonly used for tooth restoration, there is a lack of studies of treatment regimens for preventing extra-oral infection and decreasing osseointegration failures by establishing early peri-implant soft tissue seals on titanium dental implant abutments. In this study, air atmospheric-pressure plasma-jet (AAPPJ) treatment was applied to titanium disks to assay the potential for early peri-implant soft tissue seals on titanium dental implant abutment. Materials and methods. After titanium disks were treated with AAPPJ for 10 s at 250, 500, 1000 and 1500 sccm, surface analysis was performed; the control group received air only or no treatment. Human gingival fibroblasts (HGF) were seeded onto the specimens for evaluating cell attachment and proliferation and adherent-cell morphology was visualized via confocal microscopy. Results. In AAPPJ-treated specimens, the water contact angle decreased according to increased flow rate. Oxygen composition increased in XPS, but no topographical changes were detected. The effect of AAPPJ treatment at 1000 sccm was apparent 2 mm from the treated spot, with a 20% increase in early cell attachment and proliferation. Adherent HGF on AAPPJ-treated specimens displayed a stretched phenotype with more vinculin formation than the control group. Conclusions. Within the limitations of this study, the results indicate that AAPPJ treatment may enhance the early attachment and proliferation of HGF for establishing early peri-implant soft tissue seals on titanium dental implant abutments with possible favorable effects of osseointegration of dental implant. PMID:25183251

Lee, Jung-Hwan; Kim, Yong-Hee; Choi, Eun-Ha; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2015-01-01

273

Carotid Artery Disease  

MedlinePLUS

... from the NHLBI on Twitter. What Is Carotid Artery Disease? Carotid (ka-ROT-id) artery disease is ... blood to your face, scalp, and neck. Carotid Arteries Figure A shows the location of the right ...

274

Science Education in Early Childhood Teacher Education: Putting Forward a Case to Enhance Student Teachers' Confidence and Competence  

NASA Astrophysics Data System (ADS)

New Zealand is moving towards increased qualification requirements for early childhood educators. There is an underlying assumption that there is a correlation between quality early childhood education, teacher qualifications and quality practices in teaching and learning. Two fields of literature, early childhood pedagogy and science specific pedagogy, are reviewed briefly to provide a framework with which to consider why student teachers' attitudes, misunderstandings and misconceptions in science can limit their ability and willingness to create quality teaching and learning opportunities. The study reported in this paper highlights, in general, that early childhood student teachers' subject knowledge in science was poor. It also emerged that the student teachers were unaware of how little they knew and how this might affect their ability to provide appropriate science experiences for young children.

Garbett, Dawn

2003-08-01

275

Surface?enhanced Raman spectral biomarkers correlate with Ankle Brachial Index and characterize leg muscle biochemical composition of patients with peripheral arterial disease  

PubMed Central

Abstract Peripheral arterial disease (PAD) is characterized by atherosclerotic blockages of the arteries supplying the lower extremities, which cause a progressive accumulation of ischemic injury to the skeletal muscles of the lower limbs. This injury includes altered metabolic processes, damaged organelles, and compromised bioenergetics in the affected muscles. The objective of this study was to explore the association of Raman spectral signatures of muscle biochemistry with the severity of atherosclerosis in the legs as determined by the Ankle Brachial Index (ABI) and clinical presentation. We collected muscle biopsies from the gastrocnemius (calf muscle) of five patients with clinically diagnosed claudication, five patients with clinically diagnosed critical limb ischemia (CLI), and five control patients who did not have PAD. A partial least squares regression (PLSR) model was able to predict patient ABI with a correlation coefficient of 0.99 during training and a correlation coefficient of 0.85 using a full cross?validation. When using the first three PLS factor scores in combination with linear discriminant analysis, the discriminant model was able to correctly classify the control, claudicating, and CLI patients with 100% accuracy, using a full cross?validation procedure. Raman spectroscopy is capable of detecting and measuring unique biochemical signatures of skeletal muscle. These signatures can discriminate control muscles from PAD muscles and correlate with the ABI and clinical presentation of the PAD patient. Raman spectroscopy provides novel spectral biomarkers that may complement existing methods for diagnosis and monitoring treatment of PAD patients. PMID:25247767

Cluff, Kim; Kelly, Abby M.; Koutakis, Panagiotis; He, Xiang N.; Huang, Xi; Lu, Yong Feng; Pipinos, Iraklis I.; Casale, George P.; Subbiah, Jeyamkondan

2014-01-01

276

Angioplasty and stent placement - peripheral arteries  

MedlinePLUS

Percutaneous transluminal angioplasty - peripheral artery; PTA - peripheral artery; Angioplasty - peripheral arteries; iliac artery-angioplasty; fermoral artery-angioplasty; popliteal artery-angioplasty; tibial artery-angioplasty; peroneal artery- ...

277

Requirement of Multiple cis-Acting Elements in the Human Cytomegalovirus Major Immediate-Early Distal Enhancer for Viral Gene Expression and Replication  

PubMed Central

We have shown previously that the human cytomegalovirus (HCMV) major immediate-early (MIE) distal enhancer is needed for MIE promoter-dependent transcription and viral replication at low multiplicities of infection (MOI). To understand how this region works, we constructed and analyzed a series of HCMVs with various distal enhancer mutations. We show that the distal enhancer is composed of at least two parts that function independently to coordinately activate MIE promoter-dependent transcription and viral replication. One such part is contained in a 47-bp segment that has consensus binding sites for CREB/ATF, SP1, and YY1. At low MOI, these working parts likely function in cis to directly activate MIE gene expression, thus allowing viral replication to ensue. Three findings support the view that these working parts are likely cis-acting elements. (i) Deletion of either part of a bisegmented distal enhancer only slightly alters MIE gene transcription and viral replication. (ii) Reversing the distal enhancer’s orientation largely preserves MIE gene transcription and viral replication. (iii) Placement of stop codons at ?300 or ?345 in all reading frames does not impair MIE gene transcription and viral replication. Lastly, we show that these working parts are dispensable at high MOI, partly because of compensatory stimulation of MIE promoter activity and viral replication that is induced by a virion-associated component(s) present at a high viral particle/cell ratio. We conclude that the distal enhancer is a complex multicomponent cis-acting region that is required to augment both MIE promoter-dependent transcription and HCMV replication. PMID:11739696

Meier, Jeffery L.; Keller, Michael J.; McCoy, James J.

2002-01-01

278

The Role of CT Angiography of Coronaries in Early Diagnosis of Coronary Artery Plaques in Albanian People with No History of Cardiovascular Disease in Correlation with Traditional Risk Factors  

PubMed Central

Objective: To evaluate the role of CT angiography of coronaries (CTAC) in the diagnosis of subclinical atherosclerosis by detection of coronary artery plaques (CAP) in a group of consecutive albanian individuals with no history of coronary artery disease (CAD) or acute coronary syndrome and to investigate the relation between the prevalence of CAP, traditional risk factors and the expected 10-year risk of fatal cardiovascular event (CVE) based on our own experience. Method and Technique: This is a prospective study including 456 patients with no history of CAD who underwent CTAC in our hospital from September 2009 to March 2013. Risk estimation of fatal CVE was assessed using Systematic Coronary Risk Evaluation (SCORE) and then CT scan was performed with a 64 detector CT, including Ca Score and angiography of coronaries with iv contrast. Results: From 456 patients 61.4% were low risk and 32.9% were at intermediate risk according to SCORE. The prevalence of CAP diagnosed by CTAC was calculated as 55.7 % overall. Though the presence and severity of CAP increased significantly with the increase of SCORE, it was found to be 44.1% in the low risk patients and 80% in the intermediate risk group, with a presence of 17% and 25% of stenotic plaques (>50%) respectively. Significant correlation was found between all traditional risk factors and CAP. Conclusion: Although a direct relation between the prevalence of CAP, risk factors and the related 10-year risk of fatal CVE was found, there was a significant prevalence of CAP in low –intermediate risk group with a considerable presence of stenotic lesions. Also 8.3% of patients with no risk factors and 18% of the patients with Ca score 0 had CAP in CT angiography, one resulting with severe stenosis. Our results suggest once more that CT angiography is a reliable, very accurate noninvasive technique for the diagnosis of early CAD, especially in the low-intermediate risk patients compared to the traditional evaluation schemes and Ca score, thus should be considered in this group as a diagnostic guide for optimal therapy planning. PMID:25126008

Allajbeu, Iris; Hajro, Edjon; Temali, Indrit; Cekrezi, Bledi; Preza, Krenar

2014-01-01

279

The history of arterial revascularization: from Kolesov to Tector and beyond  

PubMed Central

Coronary artery bypass grafting (CABG) is the one of the most effective revascularization strategies for patients with obstructive coronary artery disease. Total arterial revascularization using one or both internal thoracic and radial arteries has been shown to improve early outcomes and reduce long-term cardiovascular morbidity. Although CABG has evolved from an experimental procedure in the early 1900’s to become one of the most commonly performed surgical procedures, there is still significant variation in grafting strategies amongst surgeons. We review the history and development of CABG with a particular emphasis on the early pioneers and the evolution of arterial grafting. PMID:23977617

Galvin, Sean D.

2013-01-01

280

STDP enhances synchrony in feedforward network STDP strengthens/weakens synapses driving late/early-spiking cells [Laurent07  

E-print Network

late/early-spiking cells [Laurent07] Olfactory neurons' spikes phase-lock (~2ms) to a 20Hz rhythm. STDP Browser 1 ©1988-2006 Wolfram Research, Inc. All rights reserved. #12;Insect olfaction pathway Olfactory associative odor-learning. Memory retrieval requires synaptic output from its intrinsic neurons, the Kenyon

Boahen, Kwabena

281

STDP enhances synchrony in feedforward network STDP strengthens/weakens synapses driving late/early-spiking cells [Laurent07  

E-print Network

late/early-spiking cells [Laurent07] Olfactory neurons' spikes phase-lock (~2ms) to a 20Hz rhythm. STDP;Insect olfaction pathway Olfactory receptor projection neuron kenyon cell -lobe neuron [Laurent07] Ablating the mushroom body abolishes associative odor-learning. Memory retrieval requires synaptic output

Boahen, Kwabena

282

STDP enhances synchrony in feedforward network STDP strengthens/weakens synapses onto late/early-spiking cells [Laurent07].  

E-print Network

/early-spiking cells [Laurent07]. Olfactory neurons' spikes phase-lock (~2ms) to a 20Hz rhythm. STDP favors firing Research, Inc. All rights reserved. #12;Insect olfaction pathway Olfactory receptor projection neuron-learning. Memory retrieval requires the output from its intrinsic neurons, the Kenyon cells. Kenyon cells fire

Boahen, Kwabena

283

Enhancing Student Services at Lorain County Community College: Early Results from the Opening Doors Demonstration in Ohio  

ERIC Educational Resources Information Center

In 2003, MDRC and a consortium of funders launched the Opening Doors demonstration to test reforms in six community colleges aimed at helping students stay in school and earn credentials. This report presents early results from the Opening Doors program at Lorain County Community College in Elyria, Ohio. The program provided intensive advising and…

Scrivener, Susan; Au, Jenny

2007-01-01

284

Requirement of multiple cis-acting elements in the human cytomegalovirus major immediate-early distal enhancer for viral gene expression and replication.  

PubMed

We have shown previously that the human cytomegalovirus (HCMV) major immediate-early (MIE) distal enhancer is needed for MIE promoter-dependent transcription and viral replication at low multiplicities of infection (MOI). To understand how this region works, we constructed and analyzed a series of HCMVs with various distal enhancer mutations. We show that the distal enhancer is composed of at least two parts that function independently to coordinately activate MIE promoter-dependent transcription and viral replication. One such part is contained in a 47-bp segment that has consensus binding sites for CREB/ATF, SP1, and YY1. At low MOI, these working parts likely function in cis to directly activate MIE gene expression, thus allowing viral replication to ensue. Three findings support the view that these working parts are likely cis-acting elements. (i) Deletion of either part of a bisegmented distal enhancer only slightly alters MIE gene transcription and viral replication. (ii) Reversing the distal enhancer's orientation largely preserves MIE gene transcription and viral replication. (iii) Placement of stop codons at -300 or -345 in all reading frames does not impair MIE gene transcription and viral replication. Lastly, we show that these working parts are dispensable at high MOI, partly because of compensatory stimulation of MIE promoter activity and viral replication that is induced by a virion-associated component(s) present at a high viral particle/cell ratio. We conclude that the distal enhancer is a complex multicomponent cis-acting region that is required to augment both MIE promoter-dependent transcription and HCMV replication. PMID:11739696

Meier, Jeffery L; Keller, Michael J; McCoy, James J

2002-01-01

285

Vapor resistant arteries  

NASA Technical Reports Server (NTRS)

A vapor block resistant liquid artery structure for heat pipes. A solid tube artery with openings is encased in the sintered material of a heat pipe wick. The openings are limited to that side of the artery which is most remote from the heat source. The liquid in the artery can thus exit the artery through the openings and wet the sintered sheath, but vapor generated at the heat source is unlikely to move around the solid wall of the artery and reverse its direction in order to penetrate the artery through the openings. An alternate embodiment uses finer pore size wick material to resist vapor entry.

Shaubach, Robert M. (Inventor); Dussinger, Peter M. (Inventor); Buchko, Matthew T. (Inventor)

1989-01-01

286

Early and long-term outcome of elective stenting of the infarct-related artery in patients with viability in the infarct-area: Rationale and design of the Viability-guided Angioplasty after acute Myocardial Infarction-trial (The VIAMI-trial)  

PubMed Central

Background Although percutaneous coronary intervention (PCI) is becoming the standard therapy in ST-segment elevation myocardial infarction (STEMI), to date most patients, even in developed countries, are reperfused with intravenous thrombolysis or do not receive a reperfusion therapy at all. In the post-lysis period these patients are at high risk for recurrent ischemic events. Early identification of these patients is mandatory as this subgroup could possibly benefit from an angioplasty of the infarct-related artery. Since viability seems to be related to ischemic adverse events, we initiated a clinical trial to investigate the benefits of PCI with stenting of the infarct-related artery in patients with viability detected early after acute myocardial infarction. Methods The VIAMI-study is designed as a prospective, multicenter, randomized, controlled clinical trial. Patients who are hospitalized with an acute myocardial infarction and who did not have primary or rescue PCI, undergo viability testing by low-dose dobutamine echocardiography (LDDE) within 3 days of admission. Consequently, patients with demonstrated viability are randomized to an invasive or conservative strategy. In the invasive strategy patients undergo coronary angiography with the intention to perform PCI with stenting of the infarct-related coronary artery and concomitant use of abciximab. In the conservative group an ischemia-guided approach is adopted (standard optimal care). The primary end point is the composite of death from any cause, reinfarction and unstable angina during a follow-up period of three years. Conclusion The primary objective of the VIAMI-trial is to demonstrate that angioplasty of the infarct-related coronary artery with stenting and concomitant use of abciximab results in a clinically important risk reduction of future cardiac events in patients with viability in the infarct-area, detected early after myocardial infarction. PMID:15538946

van Loon, Ramon B; Veen, Gerrit; Kamp, Otto; Bronzwaer, Jean GF; Visser, Cees A; Visser, Frans C

2004-01-01

287

Dietary supplementation with Astragalus polysaccharide enhances ileal digestibilities and serum concentrations of amino acids in early weaned piglets  

Microsoft Academic Search

Two experiments were conducted to evaluate the effects of dietary supplementation with Astragalus polysaccharide (APS) on growth performance, apparent ileal digestibilities (AID) of amino acids (AA), and their serum concentrations\\u000a in early weaned piglets. In Exp. 1, 60 pigs were weaned at 21 days of age (BW 7.35 ± 0.23 kg) and allocated to three treatments\\u000a (20 pigs\\/treatment), representing supplementing 0.0% (control), 0.02% colistin

F. G. Yin; Y. L. Liu; Y. L. Yin; X. F. Kong; R. L. Huang; T. J. Li; G. Y. Wu; Yongqing Hou

2009-01-01

288

Action Plan to enhance self-management and early detection of exacerbations in COPD patients; a multicenter RCT  

Microsoft Academic Search

BACKGROUND: Early detection of exacerbations by COPD patients initiating prompt interventions has shown to be clinically relevant. Until now, research failed to identify the effectiveness of a written individualized Action Plan (AP) to achieve this. METHODS\\/DESIGN: The current multicenter, single-blind RCT with a follow-up period of 6 months, evaluates the hypothesis that individualized AP's reduce exacerbation recovery time. Patients are

Jaap CA Trappenburg; Lieselotte Koevoets; Gerdien H de Weert-van Oene; Evelyn M Monninkhof; Jean Bourbeau; Thierry Troosters; Theo JM Verheij; Jan-Willem J Lammers; Augustinus JP Schrijvers

2009-01-01

289

Ocean Warming Enhances Malformations, Premature Hatching, Metabolic Suppression and Oxidative Stress in the Early Life Stages of a Keystone Squid  

PubMed Central

Background The knowledge about the capacity of organisms’ early life stages to adapt to elevated temperatures is very limited but crucial to understand how marine biota will respond to global warming. Here we provide a comprehensive and integrated view of biological responses to future warming during the early ontogeny of a keystone invertebrate, the squid Loligo vulgaris. Methodology/Principal Findings Recently-spawned egg masses were collected and reared until hatching at present day and projected near future (+2°C) temperatures, to investigate the ability of early stages to undergo thermal acclimation, namely phenotypic altering of morphological, behavioural, biochemical and physiological features. Our findings showed that under the projected near-future warming, the abiotic conditions inside the eggs promoted metabolic suppression, which was followed by premature hatching. Concomitantly, the less developed newborns showed greater incidence of malformations. After hatching, the metabolic burst associated with the transition from an encapsulated embryo to a planktonic stage increased linearly with temperature. However, the greater exposure to environmental stress by the hatchlings seemed to be compensated by physiological mechanisms that reduce the negative effects on fitness. Heat shock proteins (HSP70/HSC70) and antioxidant enzymes activities constituted an integrated stress response to ocean warming in hatchlings (but not in embryos). Conclusions/Significance The stressful abiotic conditions inside eggs are expected to be aggravated under the projected near-future ocean warming, with deleterious effects on embryo survival and growth. Greater feeding challenges and the lower thermal tolerance limits of the hatchlings are strictly connected to high metabolic demands associated with the planktonic life strategy. Yet, we found some evidence that, in the future, the early stages might support higher energy demands by adjusting some cellular functional properties to increase their thermal tolerance windows. PMID:22701620

Rosa, Rui; Pimentel, Marta S.; Boavida-Portugal, Joana; Teixeira, Tatiana; Trübenbach, Katja; Diniz, Mário

2012-01-01

290

Harvey with a modern twist: how and why conducting arteries amplify the pressure wave originating from the heart.  

PubMed

Current views on cardiovascular physiology differ little from that published by William Harvey in 1628: the heart delivers all energy for blood circulation, forcing its contents into the aorta, via arteries, arterioles and capillaries into the venous system that collects the blood and returns it to the right side of the heart. Similarly, blood from the right side passes through pulmonary arteries and arterioles to pulmonary veins before returning to the left side of the heart. However, from aorta to capillaries there is a great increase in overall cross-sectional area. The arterial system can be seen as a funnel, the heart pumping blood into its narrow end. Theoretically, this implies that pulsatile energy delivered by the heart dilutes significantly along its way through the arterial tree. Also, unfavorable tissue conditions, such as elevated pressure, impede proper perfusion when blood can pass just as easy through adjacent capillary systems. Finally, blood will experience more resistance to flow for capillary systems more distant to the heart due to its longer trajectory. This implies that capillary systems closer to the heart are more easily perfused than more distant ones. In reality, the pulse from the heart has been shown to increase and accelerate towards periphery. This, together with transcranial Doppler observations on the variation in wave morphology in intracranial arteries, for instance during CO2-reactivity testing and during cardiac arrhythmia, has led to the theory of arterial acceleration: at stroke onset, the arterial pressure wave resulting from myocardial contraction is enhanced by a short-lasting and well-synchronised contraction within the smooth muscle layers of conducting arteries. This results in a temporary 'stiffening' of the arterial tree by which cardiac pressure during early systole is amplified and distributed into all the body's capillary systems. This theory would overcome all theoretical and observational concerns sketched above. Such arterial acceleration limited to the first 100-150 ms of every heart beat would augment, accelerate and distribute the pulse generated by heart contraction over the full length and branching of the arterial tree, thereby enforcing a widespread tissue perfusion. It is obvious that the theory of arterial acceleration is a major shift of paradigm forcing us to reconsider many aspects of cardiovascular physiology. Moreover, it improves our understanding how blood expelled by the heart through the small lumen of the aortic notch has sufficient energy to reach every nook and cranny of our body. PMID:24613738

Schaafsma, A

2014-05-01

291

Sand remobilization enhanced complexity to mounded geometry, Early Tertiary deep water sand reservoirs, Balder Oil Field North Sea  

SciTech Connect

Sand remobilization played a major role in generating the high relief mounded geometries that trap oil in the early Tertiary reservoirs at Balder Field in Norwegian North Sea blocks 25/10 and 25/11. The thick massive submarine-fan sandstones were shed from the East Shetland Platform and deposited from high density turbidity currents. These thick massive sandstones lie in the distal portions of the fan system on the northwestern margin of the Utsira High. An intricate interaction between deposition and soft sediment deformation processes generated the complex cluster of thick mounded sand geometries comprising the Balder oil field. Slumping, sliding and sand remobilization with associated sand injections into overlying shales were the dominant deformation processes that mainly occurred during the early Eocene. The field is comprised of three reservoirs, the Paleocene Heimdal and Hermod Formations and the Early Eocene Balder Formation. The sandstones, which have excellent reservoir properties, share a common pressure system and oil-water contact. This is probably related to the soft-sediment deformation and associated sand injections establishing cross-stratal communication.

Bergslien, D.; Rye-Larsen, M.; Jenssen, A.I. (Esso Norge AS, Forus (Norway))

1996-01-01

292

Sand remobilization enhanced complexity to mounded geometry, Early Tertiary deep water sand reservoirs, Balder Oil Field North Sea  

SciTech Connect

Sand remobilization played a major role in generating the high relief mounded geometries that trap oil in the early Tertiary reservoirs at Balder Field in Norwegian North Sea blocks 25/10 and 25/11. The thick massive submarine-fan sandstones were shed from the East Shetland Platform and deposited from high density turbidity currents. These thick massive sandstones lie in the distal portions of the fan system on the northwestern margin of the Utsira High. An intricate interaction between deposition and soft sediment deformation processes generated the complex cluster of thick mounded sand geometries comprising the Balder oil field. Slumping, sliding and sand remobilization with associated sand injections into overlying shales were the dominant deformation processes that mainly occurred during the early Eocene. The field is comprised of three reservoirs, the Paleocene Heimdal and Hermod Formations and the Early Eocene Balder Formation. The sandstones, which have excellent reservoir properties, share a common pressure system and oil-water contact. This is probably related to the soft-sediment deformation and associated sand injections establishing cross-stratal communication.

Bergslien, D.; Rye-Larsen, M.; Jenssen, A.I. [Esso Norge AS, Forus (Norway)

1996-12-31

293

Mitochondrial reactive oxygen species enhance AMP-activated protein kinase activation in the endothelium of patients with coronary artery disease and diabetes.  

PubMed

The aim of the present study was to determine whether the endothelial dysfunction associated with CAD (coronary artery disease) and T2D (Type 2 diabetes mellitus) is concomitant with elevated mtROS (mitochondrial reactive oxygen species) production in the endothelium and establish if this, in turn, regulates the activity of endothelial AMPK (AMP-activated protein kinase). We investigated endothelial function, mtROS production and AMPK activation in saphenous veins from patients with advanced CAD. Endothelium-dependent vasodilation was impaired in patients with CAD and T2D relative to those with CAD alone. Levels of mitochondrial H(2)O(2) and activity of AMPK were significantly elevated in primary HSVECs (human saphenous vein endothelial cells) from patients with CAD and T2D compared with those from patients with CAD alone. Incubation with the mitochondria-targeted antioxidant, MitoQ(10) significantly reduced AMPK activity in HSVECs from patients with CAD and T2D but not in cells from patients with CAD alone. Elevated mtROS production in the endothelium of patients with CAD and T2D increases AMPK activation, supporting a role for the kinase in defence against oxidative stress. Further investigation is required to determine whether pharmacological activators of AMPK will prove beneficial in the attenuation of endothelial dysfunction in patients with CAD and T2D. PMID:23057846

Mackenzie, Ruth M; Salt, Ian P; Miller, William H; Logan, Angela; Ibrahim, Hagar A; Degasperi, Andrea; Dymott, Jane A; Hamilton, Carlene A; Murphy, Michael P; Delles, Christian; Dominiczak, Anna F

2013-03-01

294

Bilateral superficial median arteries  

PubMed Central

A superficial artery may be present in the forearm, arising from the axillary, brachial or superficial brachial arteries and crossing over the origin of the flexor muscles of the forearm to reach the palm (Adachi, 1928; Bergman et al. 1988). When this superficial artery continues as the normal ulnar artery accompanying the ulnar nerve at the wrist, it is referred to as the superficial ulnar artery, with an incidence of ?4%. When the artery passes below or superficial to the flexor retinaculum in the middle of the forearm, sometimes continuing to join the superficial palmar arch, it is called the superficial median artery, with an incidence of ?1%. We have observed a relatively rare variation involving the presence of a superficial median artery in both upper limbs. We discuss the clinical importance and the developmental aspects of this arterial variation. PMID:10386784

NAKATANI, TOSHIO; IZUMI, ATSUSHI; TANAKA, SHIGENORI

1999-01-01

295

Enhanced G2 chromatid radiosensitivity, an early stage in the neoplastic transformation of human epidermal keratinocytes in culture  

SciTech Connect

A deficiency in DNA repair, manifest as enhanced chromatid radiosensitivity during the G2 phase of the cell cycle, together with a proliferative stimulus such as that provided by active oncogenes may be necessary and sufficient for the malignant neoplastic transformation of human keratinocytes in culture. Normal epidermal keratinocytes established as continuous cell lines by transfection with pSV3-neo or infection with adeno 12-SV40 hybrid virus developed enhanced G2 chromatid radiosensitivity after 18 passages in culture. In contrast to cells from primary or secondary culture, these cells could be transformed to malignant neoplastic cells by infection with Kirsten murine sarcoma virus containing the Ki-ras oncogene or in one line by the chemical carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine; both of these agents produced a marked proliferative response. Cytological heterogeneity and karyotypic instability characterized the cells during their progression to neoplasia. These results are interpreted in terms of a mechanism for neoplastic transformation.

Gantt, R.; Sanford, K.K.; Parshad, R.; Price, F.M.; Peterson, W.D. Jr.; Rhim, J.S.

1987-03-01

296

Extensive complement-dependent enhancement of HIV1 by autologous non-neutralising antibodies at early stages of infection  

Microsoft Academic Search

Background  Non-neutralising antibodies to the envelope glycoprotein are elicited during acute HIV-1 infection and are abundant throughout\\u000a the course of disease progression. Although these antibodies appear to have negligible effects on HIV-1 infection when assayed\\u000a in standard neutralisation assays, they have the potential to exert either inhibitory or enhancing effects through interactions\\u000a with complement and\\/or Fc receptors. Here we report that

Suzanne Willey; Marlén MI Aasa-Chapman; Stephen O’Farrell; Pierre Pellegrino; Ian Williams; Robin A Weiss; Stuart JD Neil

2011-01-01

297

An alternative estimation of the RF-enhanced plasma temperature during SPEAR artificial heating experiments: Early results  

NASA Astrophysics Data System (ADS)

RF heating of the F region plasma at high latitudes has long been known to produce electron temperature increases that can vary from tens to hundreds of percent above the background, unperturbed level. In contrast, artificial ionospheric modification experiments conducted using the Space Plasma Exploration by Active Radar (SPEAR) heating facility on Svalbard have often failed to produce obvious enhancements in the electron temperatures when measured using the European Incoherent Scatter Svalbard radar (ESR), colocated with the heater. Contamination of the ESR ion line spectra by the zero-frequency purely growing mode (PGM) feature is known to persist at varying amplitudes throughout SPEAR heating, and such spectral features can lead to significant temperature underestimations when the incoherent scatter spectra are analyzed using conventional methods. In this study, we present the first results of applying a recently developed technique to correct the PGM-contaminated spectra to SPEAR-enhanced ESR spectra and derive an alternative estimate of the SPEAR-heated electron temperature. We discuss how the effectiveness of the spectrum corrections can be affected by the data variance, estimated over the integration period. The subsequent electron temperatures, inferred from corrected spectra, range from a few tens to a few hundred Kelvin above the average background temperature. These temperatures are found to be in reasonable agreement with the theoretical “enhanced” temperature, calculated for the peak of the stationary temperature perturbation profile, when realistic absorption effects are accounted for.

Vickers, H.; Baddeley, L.

2011-11-01

298

Sustained hypoxia leads to the emergence of cells with enhanced growth, migratory, and promitogenic potentials within the distal pulmonary artery wall  

PubMed Central

All forms of chronic pulmonary hypertension (PH) are characterized by structural remodeling of the pulmonary artery (PA) media, a process previously attributed solely to changes in the phenotype of resident smooth muscle cells (SMC). However, recent experimental evidence in both systemic and pulmonary circulations suggests that other cell types, including circulating and local progenitors, contribute significantly to this process. The goal of this study was to determine if hypoxia-induced remodeling of distal PA (dPA) media involves the emergence of cells with phenotypic and functional characteristics distinct from those of resident dPA SMC and fibroblasts. In vivo, in contrast to the phenotypically uniform SMC composition of dPA media in control calves, the remodeled dPA media of neonatal calves with severe hypoxia-induced PH comprised cells exhibiting a distinct phenotype, including the expression of hematopoetic (CD45), leukocytic/monocytic (CD11b, CD14), progenitor (cKit), and motility-associated (S100A4) cell markers. Consistent with these in vivo observations, primary cell cultures isolated from dPA media of hypertensive calves yielded not only differentiated SMC, but also smaller, morphologically rhomboidal (thus termed here “R”) cells that transiently expressed CD11b, constitutively expressed the mesenchymal cell marker type I procollagen, expressed high mRNA levels of progenitor cell markers cKit, CD34, CD73, as well as for inflammatory mediators, IL-6 and MCP-1, and, with time in culture, gained expression of a myofibroblast marker, ?-SM-actin. R cells exhibited highly augmented proliferative, migratory, invasive, and potent promitogenic capabilities, which were due, at least in part, to the production of PDGFs, SDF-1/CXCL12, and S100A4. These data suggest that the cellular mechanisms of dPA remodeling include the emergence of cells with phenotypic and functional characteristics markedly distinct from those of resident dPA cells. PMID:19767409

Li, Min; Gnanasekharan, Meena; Burke, Danielle L.; Fragoso, Miguel; Strassheim, Derek; Sylman, Joanna L.; Stenmark, Kurt R.

2009-01-01

299

Phospholipase A 2 activation as a therapeutic approach for cognitive enhancement in early-stage Alzheimer disease  

Microsoft Academic Search

Rationale  Alzheimer disease (AD) is the leading cause of dementia in the elderly and has no known cure. Evidence suggests that reduced\\u000a activity of specific subtypes of intracellular phospholipases A2 (cPLA2 and iPLA2) is an early event in AD and may contribute to memory impairment and neuropathology in the disease.\\u000a \\u000a \\u000a \\u000a Objective  The objective of this study was to review the literature focusing

Evelin L. Schaeffer; Orestes V. Forlenza; Wagner F. Gattaz

2009-01-01

300

Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery: Diagnosis with CT Angiography.  

PubMed

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly. It is associated with early infant mortality and sudden death in adults. Traditionally, ALCAPA has been diagnosed by angiography or autopsy; however, the development of cardiac computed tomography (CT) and magnetic resonance imaging (MRI) has allowed noninvasive evaluation of the coronary anatomy by direct visualization of the origin of the left coronary artery (LCA) from the pulmonary artery. We report a case of 10-year-old girl who has been on follow up for dilated cardiomyopathy for 4 years. The definitive diagnosis of ALCAPA is reached by multislice computed tomography (MSCT). The MSCT scan showed an anomalous origin of LCA from the pulmonary trunk, with a tortuous and dilated right coronary artery and right-to-left collateralization. Consequently, the patient was successfully treated with surgery. PMID:23607073

Oncel, Guray; Oncel, Dilek

2013-01-01

301

Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery: Diagnosis with CT Angiography  

PubMed Central

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly. It is associated with early infant mortality and sudden death in adults. Traditionally, ALCAPA has been diagnosed by angiography or autopsy; however, the development of cardiac computed tomography (CT) and magnetic resonance imaging (MRI) has allowed noninvasive evaluation of the coronary anatomy by direct visualization of the origin of the left coronary artery (LCA) from the pulmonary artery. We report a case of 10-year-old girl who has been on follow up for dilated cardiomyopathy for 4 years. The definitive diagnosis of ALCAPA is reached by multislice computed tomography (MSCT). The MSCT scan showed an anomalous origin of LCA from the pulmonary trunk, with a tortuous and dilated right coronary artery and right-to-left collateralization. Consequently, the patient was successfully treated with surgery. PMID:23607073

Oncel, Guray; Oncel, Dilek

2013-01-01

302

Arterial Mechanical Changes in Children With Familial Hypercholesterolemia  

Microsoft Academic Search

Atherosclerosis is preceded by a phase of changes in the arterial wall that could have functional consequences even before the appearance of atheromatous changes. We hypothesized that early alterations of the mechanical properties of the arterial wall could precede clinical and echographic modifications. We used an automatic, computerized, ultrasonic procedure to evaluate geometric and mechanical characteristics of the common carotid

Yacine Aggoun; Damien Bonnet; Daniel Sidi; Jean Philippe Girardet; Eric Brucker; Michel Polak; Michel E. Safar; Bernard I. Levy

2009-01-01

303

Clinical measurement of arterial stiffness obtained from noninvasive pressure waveforms  

Microsoft Academic Search

Aortic pulse wave velocity (PWV) and augmentation index are independent predictors of adverse cardiovascular events, including mortality. In hypertension and aging, central elastic arteries become stiffer, diastolic pressure decreases, and central systolic and pulse pressures are augmented due to increased PWV and early return of reflected waves to the heart from the periphery. Valuable information on arterial properties such as

Wilmer W. Nichols

2005-01-01

304

Arterial Stiffness in the Young: Assessment, Determinants, and Implications  

PubMed Central

Arterial stiffness describes the rigidity of the arterial wall. Its significance owes to its relationship with the pulsatile afterload presented to the left ventricle and its implications on ventricular-arterial coupling. In adults, the contention that arterial stiffness as a marker and risk factor for cardiovascular morbidity and mortality is gaining support. Noninvasive methods have increasingly been adopted in both the research and clinical arena to determine local, segmental, and systemic arterial stiffness in the young. With adoption of these noninvasive techniques for use in children and adolescents, the phenomenon and significance of arterial stiffening in the young is beginning to be unveiled. The list of childhood factors and conditions found to be associated with arterial stiffening has expanded rapidly over the last decade; these include traditional cardiovascular risk factors, prenatal growth restriction, vasculitides, vasculopathies associated with various syndromes, congenital heart disease, and several systemic diseases. The findings of arterial stiffening have functional implications on energetic efficiency, structure, and function of the left ventricle. Early identification of arterial dysfunction in childhood may provide a window for early intervention, although longitudinal studies are required to determine whether improvement of arterial function in normal and at-risk paediatric populations will be translated into clinical benefits. PMID:20421954

2010-01-01

305

The Contribution of Arterial Calcification to Peripheral Arterial Disease in Pseudoxanthoma Elasticum  

PubMed Central

Background and aims The contribution of arterial calcification (AC) in peripheral arterial disease (PAD) and arterial wall compressibility is a matter of debate. Pseudoxanthoma elasticum (PXE), an inherited metabolic disease due to ABCC6 gene mutations, combines elastic fiber fragmentation and calcification in various soft tissues including the arterial wall. Since AC is associated with PAD, a frequent complication of PXE, we sought to determine the role of AC in PAD and arterial wall compressibility in this group of patients. Methods and Results Arterial compressibility and patency were determined by ankle-brachial pressure index (ABI) in a cohort of 71 PXE patients (mean age 48±SD 14 yrs, 45 women) and compared to 30 controls without PAD. Lower limb arterial calcification (LLAC) was determined by non-contrast enhanced helicoidal CT-scan. A calcification score (Ca-score) was computed for the femoral, popliteal and sub-popliteal artery segments of both legs. Forty patients with PXE had an ABI<0.90 and none had an ABI>1.40. LLAC increased with age, significantly more in PXE subjects than controls. A negative association was found between LLAC and ABI (r?=??0.363, p?=?0.002). The LLAC was independently associated with PXE and age, and ABI was not linked to cardiovascular risk factors. Conclusions The presence of AC was associated with PAD and PXE without affecting arterial compressibility. PAD in PXE patients is probably due to proximal obstructive lesions developing independently from cardiovascular risk factors. PMID:24800819

Leftheriotis, Georges; Kauffenstein, Gilles; Hamel, Jean François; Abraham, Pierre; Le Saux, Olivier; Willoteaux, Serge; Henrion, Daniel; Martin, Ludovic

2014-01-01

306

Cooled artery extension  

NASA Technical Reports Server (NTRS)

An artery vapor trap. A heat pipe artery is constructed with an extension protruding from the evaporator end of the heat pipe beyond the active area of the evaporator. The vapor migrates into the artery extension because of gravity or liquid displacement, and cooling the extension condenses the vapor to liquid, thus preventing vapor lock in the working portion of the artery by removing vapor from within the active artery. The condensed liquid is then transported back to the evaporator by the capillary action of the artery extension itself or by wick located within the extension.

Gernert, Nelson J. (Inventor)

1990-01-01

307

Acute ST-segment elevation myocardial infarction treated with delayed angioplasty in a patient with anomalous origin of the right coronary artery in the early phase after kidney transplantation  

PubMed Central

This case demonstrates a rare anomalous of origin of right coronary artery from the left sinus of Valsalva in patients who underwent kidney transplantation complicated by an acute ST elevation myocardial infarction treated with delay angioplasty. PMID:25489331

Wretowski, Dominik; ?abyk, Andrzej; Kostrubiec, Maciej; P?ywaczewska, Magdalena; Sawicki, Rafa?; Jankowski, Krzysztof; Pruszczyk, Piotr

2014-01-01

308

The history of chemical enrichment and the sites of early nucleosynthesis: CNO abundances of galactic carbon-enhanced metal-poor stars  

NASA Astrophysics Data System (ADS)

This dissertation focuses on abundance analyses of carbon-enhanced metal-poor (CEMP) Galactic halo stars. Different methods for determining carbon, nitrogen, oxygen, and also some barium abundances are described. The study of these abundances in such stars serves to investigate the means by which the Universe became enriched in metals. Due to the different kinds of CEMP stars observed in the Milky Way, it can only be assumed that there is certainly more than one method of carbon-enhancement at early times. Complete abundance analyses for as many of these archaeological relics as possible are needed in order to constrain the astrophysical sites of early carbon production. There are three main parts of this dissertation. The first part describes new techniques to determine oxygen abundances from spectra of the near-infrared molecular CO bands. With the near-IR OSIRIS spectrograph on the SOAR 4.1-m telescope, 57 CEMP stars were observed. A wide range of oxygen abundances were estimated, and the results were statistically compared to high-resolution estimates for both carbon-enhanced and carbon-normal metal-poor stars. Abundance patterns of the sample stars were compared to yield predictions for very metal-poor asymptotic giant branch (AGB) stars. The majority of the sample exhibit patterns consistent with CEMP stars having s-process-element enhancements, and thus have very likely been polluted by carbon- and oxygen-enhanced material transferred from a metal-poor AGB companion. The second part delineates a new survey effort implemented in order to identify new CEMP stars. For the initial pilot study, a new selection technique was developed based solely on the strength of the CH G band at 4300 A. This technique eliminated previous temperature and metallicity biases present in other CEMP surveys. Observations of the pilot sample were carried out with the Goodman HTS spectrograph on the SOAR 4.1-m telescope. Of the over 120 candidate stars observed, over 35% were found to be CEMP stars. The selection technique was then improved to include a second index for the strength of the G band, and the survey was continued on both the SOAR and Gemini telescopes. After this extension, the success rate of this program increased to 50%. The final part of this dissertation contains details of a pilot study of known metal-poor stars using the X-Shooter spectrograph on the Very Large Telescope (VLT). With three spectrograph arms (near-ultraviolet, optical, and near-infrared), this instrument was used to calculate carbon, nitrogen, oxygen, and barium abundances for a sample of 27 CEMP stars. The broad spectral range of this instrument is unprecedented, and it is an efficient way to estimate abundances for several pertinent species in just one exposure per star. Of the 27 stars, many proved to be enhanced in carbon. The majority appear to be consistent with s-process-element enhancement, but there was one extremely metal-poor star which falls into the rare family of CEMP stars with no neutron-capture-element enhancement.

Kennedy, Catherine R.

309

Uveal Melanoma Metastatic to the Liver: The Role of Quantitative Volumetric Contrast-Enhanced MR Imaging in the Assessment of Early Tumor Response after Transarterial Chemoembolization1  

PubMed Central

PURPOSE To determine whether volumetric changes of enhancement as seen on contrast-enhanced magnetic resonance (MR) imaging can help assess early tumor response and predict survival in patients with metastatic uveal melanoma after one session of transarterial chemoembolization (TACE). MATERIALS AND METHODS Fifteen patients with 59 lesions who underwent MR imaging before and 3 to 4 weeks after the first TACE were retrospectively included. MR analysis evaluated signal intensities, World Health Organization (WHO), Response Evaluation Criteria in Solid Tumors (RECIST), European Association for the Study of the Liver (EASL), modified RECIST (mRECIST), tumor volume [volumetric RECIST (vRECIST)], and volumetric tumor enhancement [quantitative EASL (qEASL)]. qEASL was expressed in cubic centimeters [qEASL (cm3)] and as a percentage of the tumor volume [qEASL (%)]. Paired t test with its exact permutation distribution was used to compare measurements before and after TACE. The Kaplan-Meier method with the log-rank test was used to calculate overall survival for responders and non-responders. RESULTS In target lesions, mean qEASL (%) decreased from 63.9% to 42.6% (P = .016). No significant changes were observed using the other response criteria. In non-target lesions, mean WHO, RECIST, EASL, mRECIST, vRECIST, and qEASL (cm3) were significantly increased compared to baseline. qEASL (%) remained stable (P = .214). Median overall survival was 5.6 months. qEASL (cm3) was the only parameter that could predict survival based on target lesions (3.6 vs 40.5 months, P < .001) or overall (target and non-target lesions) response (4.4 vs 40.9 months, P = .001). CONCLUSION Volumetric tumor enhancement may be used as a surrogate biomarker for survival prediction in patients with uveal melanoma after the first TACE. PMID:24953419

Duran, Rafael; Chapiro, Julius; Frangakis, Constantine; Lin, MingDe; Schlachter, Todd R.; Schernthaner, Rüdiger E.; Wang, Zhijun; Savic, Lynn J.; Tacher, Vania; Kamel, Ihab R.; Geschwind, Jean-François

2014-01-01

310

Helical Carbon Nanotubes Enhance the Early Immune Response and Inhibit Macrophage-Mediated Phagocytosis of Pseudomonas aeruginosa  

PubMed Central

Aerosolized or aspirated manufactured carbon nanotubes have been shown to be cytotoxic, cause pulmonary lesions, and demonstrate immunomodulatory properties. CD-1 mice were used to assess pulmonary toxicity of helical carbon nanotubes (HCNTs) and alterations of the immune response to subsequent infection by Pseudomonas aeruginosa in mice. HCNTs provoked a mild inflammatory response following either a single exposure or 2X/week for three weeks (multiple exposures) but were not significantly toxic. Administering HCNTs 2X/week for three weeks resulted in pulmonary lesions including granulomas and goblet cell hyperplasia. Mice exposed to HCNTs and subsequently infected by P. aeruginosa demonstrated an enhanced inflammatory response to P. aeruginosa and phagocytosis by alveolar macrophages was inhibited. However, clearance of P. aeruginosa was not affected. HCNT exposed mice depleted of neutrophils were more effective in clearing P. aeruginosa compared to neutrophil-depleted control mice, accompanied by an influx of macrophages. Depletion of systemic macrophages resulted in slightly inhibited bacterial clearance by HCNT treated mice. Our data indicate that pulmonary exposure to HCNTs results in lesions similar to those caused by other nanotubes and pre-exposure to HCNTs inhibit alveolar macrophage phagocytosis of P. aeruginosa. However, clearance was not affected as exposure to HCNTs primed the immune system for an enhanced inflammatory response to pulmonary infection consisting of an influx of neutrophils and macrophages. PMID:24324555

Walling, Brent E.; Kuang, Zhizhou; Hao, Yonghua; Estrada, David; Wood, Joshua D.; Lian, Feifei; Miller, Lou Ann; Shah, Amish B.; Jeffries, Jayme L.; Haasch, Richard T.; Lyding, Joseph W.; Pop, Eric; Lau, Gee W.

2013-01-01

311

Embryos of Robertsonian Translocation Carriers Exhibit a Mitotic Interchromosomal Effect That Enhances Genetic Instability during Early Development  

PubMed Central

Balanced chromosomal rearrangements represent one of the most common forms of genetic abnormality affecting approximately 1 in every 500 (0.2%) individuals. Difficulties processing the abnormal chromosomes during meiosis lead to an elevated risk of chromosomally abnormal gametes, resulting in high rates of miscarriage and/or children with congenital abnormalities. It has also been suggested that the presence of chromosome rearrangements may also cause an increase in aneuploidy affecting structurally normal chromosomes, due to disruption of chromosome alignment on the spindle or disturbance of other factors related to meiotic chromosome segregation. The existence of such a phenomenon (an inter-chromosomal effect—ICE) remains controversial, with different studies presenting contradictory data. The current investigation aimed to demonstrate conclusively whether an ICE truly exists. For this purpose a comprehensive chromosome screening technique, optimized for analysis of minute amounts of tissue, was applied to a unique collection of samples consisting of 283 oocytes and early embryos derived from 44 patients carrying chromosome rearrangements. A further 5,078 oocytes and embryos, derived from chromosomally normal individuals of identical age, provided a robust control group for comparative analysis. A highly significant (P?=?0.0002) increase in the rate of malsegregation affecting structurally normal chromosomes was observed in association with Robertsonian translocations. Surprisingly, the ICE was clearly detected in early embryos from female carriers, but not in oocytes, indicating the possibility of mitotic rather than the previously suggested meiotic origin. These findings have implications for our understanding of genetic stability during preimplantation development and are of clinical relevance for patients carrying a Robertsonian translocation. The results are also pertinent to other situations when cellular mechanisms for maintaining genetic fidelity are relaxed and chromosome rearrangements are present (e.g. in tumors displaying chromosomal instability). PMID:23133396

Alfarawati, Samer; Fragouli, Elpida; Colls, Pere; Wells, Dagan

2012-01-01

312

Coronary Artery Bypass  

MedlinePLUS

... procedures performed each year in the United States. Arteries can become clogged over time by the buildup ... bypass" around a section of clogged or diseased artery. The surgery involves using a section of blood ...

313

Coronary Artery Disease  

MedlinePLUS

Coronary artery disease (CAD) is the most common type of heart disease. It is the leading cause of death ... both men and women. CAD happens when the arteries that supply blood to heart muscle become hardened ...

314

Carotid Artery Disease  

MedlinePLUS

... cerebrovascular disease, stroke, transient ischemic attacks (TIA) Carotid artery disease is a form of disease that affects ... to the brain by the 2 large carotid arteries in the front of your neck and by ...

315

Transit & Arterial Performance  

E-print Network

Transit & Arterial Performance Michael Wolfe & Mathew Berkow A Study of the Barbur Boulevard arterial performance in a corridor using both advance and system loop data · Ultimately, marry the two data

Bertini, Robert L.

316

Arterial pulse wave velocity in coronary arteries  

Microsoft Academic Search

Pulse wave velocity is related to arterial stiffness. Pulse wave velocity changes with age and disease and is a useful indicator of cardiovascular disease. Different methods are used for evaluating pulse wave velocity in systemic vessels, but none is applicable to coronary arteries. In this study we first compare values of wave speed (c) calculated from measurements of pressure (P)

J. Aguado-Sierra; K. H. Parker; J. E. Davies; D. Francis; A. D. Hughes; J. Mayer

2006-01-01

317

Centripetal spread of arterial collateral endothelial cell hyperplasia after renal artery stenosis in the rat.  

PubMed

The factors responsible for collateral arterial growth after major artery occlusion remain obscure, despite their importance for tissue survival. An increase in endothelial cell labelling with tritiated thymidine, as an index of collateral arterial growth, occurs early after renal artery occlusion. Our working premise was that an increase in endothelial cell labelling would occur simultaneously throughout the length of the collateral arteries if biophysical factors related to blood flow were the responsible mechanism, because blood flow must be increased simultaneously throughout the length of the small, preformed collateral arterial vessels. On the other hand, if the information spread from the ischemic zone, one would anticipate centripetal spread of the endothelial cell hyperplasia in a retrograde direction from the ischemic zone. With the periureteric collateral arterial supply as the model, we performed serial studies of tritiated thymidine labelling following renal artery stenosis in the rat. As anticipated, endothelial cell labelling rose sharply within 24 to 48 hours, first evident in the area immediately adjacent to the renal hilum. Thereafter, a progressive, time-related centripetal gradient in endothelial cell tritiated thymidine labelling occurred (p less than 0.01). These findings indicate that the factors responsible for endothelial cell hyperplasia are less related to blood flow in the lumen than to downstream, ischemic events. Although the mechanism responsible for the centripetal spread remains speculative, the communication system is likely to involve cell-to-cell contact in the vessel wall. PMID:3581447

Hollenberg, N K; Odori, T

1987-03-01

318

Gadolinium susceptibility artifact causing false positive stenosis isolated to the proximal common carotid artery in 3D dynamic contrast medium enhanced MR angiography of the thorax--a brief review of causes and prevention.  

PubMed

Due to the close proximity of arteries and veins in the superior mediastinum and upper extremities, T2* shortening effects of the gadolinium within the central veins may cause artifactual vascular stenosis (susceptibility artifact) on arterial-phase MR angiographic images of the major branches of the aortic arch. We report a case of artifactual stenosis isolated to the origin of the left common carotid artery on arterial-phase MR angiography, secondary to susceptibility artifact from non-diluted gadolinium in the adjacent brachiocephalic vein. The cause of the artifact, its identification and prevention is reviewed. PMID:12749396

Tirkes, A Temel; Rosen, Mark A; Siegelman, Evan S

2003-04-01

319

Blood Flow in Arteries  

Microsoft Academic Search

Blood flow in arteries is dominated by unsteady flow phenomena. The cardiovascular system is an internal flow loop with multiple branches in which a complex liquid circulates. A nondimensional frequency parameter, the Womersley number, governs the relationship between the unsteady and viscous forces. Normal arterial flow is laminar with secondary flows generated at curves and branches. The arteries are living

David N. Ku

1997-01-01

320

Inflammation, Atherosclerosis, and Coronary Artery Disease  

Microsoft Academic Search

ecent research has shown that inflammation plays a key role in coronary artery disease (CAD) and other manifestations of atherosclerosis. Immune cells dominate early atherosclerotic lesions, their effector molecules accelerate progression of the lesions, and activation of inflammation can elicit acute coronary syndromes. This review highlights the role of inflammation in the pathogen- esis of atherosclerotic CAD. It will recount

Göran K. Hansson

2005-01-01

321

Early quantification of the therapeutic efficacy of the vascular disrupting agent, CKD-516, using dynamic contrast-enhanced ultrasonography in rabbit VX2 liver tumors  

PubMed Central

Purpose: To evaluate the usefulness of dynamic contrast-enhanced ultrasonography (DCE-US) in the early quantification of hemodynamic change following administration of the vascular disrupting agent (VDA) CKD-516 using a rabbit VX2 liver tumor model. Methods: This study was approved by our institutional animal care and use committee. Eight VX2 liver-tumor-bearing rabbits were treated with intravenous CKD-516, and all underwent DCE-US using SonoVue before and again 2, 4, 6, and 24 hours following their treatment. The tumor perfusion parameters were obtained from the time-intensity curve of the DCE-US data. Repeated measures analysis of variance was performed to assess any significant change in tumor perfusion over time. Relative changes in the DCE-US parameters between the baseline and follow-up assessments were correlated with the relative changes in tumor size over the course of seven days using Pearson correlation. Results: CKD-516 treatment resulted in significant changes in the DCE-US parameters, including the peak intensity, total area under the time-intensity curve (AUCtotal), and AUC during wash-out (AUCout) over time (P<0.05). Pairwise comparison tests revealed that the AUCtotal and AUC during wash-in (AUCin) seen on the two-hour follow-up were significantly lower than the baseline values (P<0.05). However, none of early changes in the DCE-US parameters until 24-hour follow-up showed a significant correlation with the relative changes in tumor size during seven days after CKD-516 treatment. Conclusion: Our results suggest that a novel VDA (CKD-516) can cause disruption of tumor perfusion as early as two hours after treatment and that the therapeutic effect of CKD-516 treatment can be effectively quantified using DCE-US. PMID:24936491

2014-01-01

322

Experimental diabetes induces hyperreactivity of rabbit renal artery to 5-hydroxytryptamine.  

PubMed

The influence of diabetes on the response of isolated rabbit renal arteries to 5-hydroxytryptamine (5-HT) was examined. 5-HT induced a concentration-related contraction that was higher in arteries from diabetic rabbits than in arteries from control rabbits. Endothelium removal did not significantly modify 5-HT contractions in arteries from control rabbits but enhanced the response to 5-HT in arteries from diabetic rabbits. Incubation with N(G)-nitro-L-arginine (L-NA) enhanced contractions to 5-HT in arteries from control and diabetic rabbits. In arteries with endothelium, this L-NA enhancement was lower in diabetic rabbits than in control rabbits. In arteries without endothelium, incubation with L-NA enhanced the maximal contractions to 5-HT in control rabbits but did not in diabetic rabbits. Indomethacin inhibited 5-HT-induced contraction of arteries from control rabbits and enhanced the maximal contraction to 5-HT of arteries from diabetic rabbits. In summary, diabetes enhances contractile response of rabbit renal artery to 5-HT. In control animals, this response is regulated by both endothelial and non-endothelial (neuronal) nitric oxide (NO) and by a vasoconstrictor prostanoid. Diabetes impairs the release of non-endothelial NO and the vasoconstrictor prostanoid. PMID:11937101

Miranda, Francisco J; Alabadí, José A; Lloréns, Silvia; Ruiz de Apodaca, Rosa F; Centeno, José M; Alborch, Enrique

2002-03-29

323

Photobleaching of arterial autofluorescence for immunofluorescence applications.  

PubMed

Immunohistochemical localization of low-level antigens in the arterial vasculature is complicated by the presence of complex molecules such as collagen, elastin, cholesterol, and fluorescent lipids that exhibit autofluorescence over a wide spectrum of wavelengths. UV irradiation of arterial vasculature has remained ineffective in preparing samples for immunofluorescent staining because of the recovery of the endogenous fluorescence within a short time following treatment. Therefore, we sought to further enhance the signal-to-noise ratio in arteries by optimizing the photobleaching of this tissue. We report here that the use of filtered sunlight significantly reduces arterial autofluorescence compared to standard UV shortwave and longwave irradiation and maintains multiple antigen epitopes suitable for immunohistochemical analysis. Using this method, we localized low-level laminin-5 isoform expression in situ, which was previously indistinguishable from endogenous autofluorescence. PMID:11314262

Kingsley, K; Carroll, K; Huff, J L; Plopper, G E

2001-04-01

324

Community Engagement to Enhance Child Survival and Early Development in Low- and Middle-Income Countries: An Evidence Review  

PubMed Central

As part of a broader evidence summit, USAID and UNICEF convened a literature review of effective means to empower communities to achieve behavioral and social changes to accelerate reductions in under-5 mortality and optimize early child development. The authors conducted a systematic review of the effectiveness of community mobilization and participation that led to behavioral change and one or more of the following: child health, survival, and development. The level and nature of community engagement was categorized using two internationally recognized models and only studies where the methods of community participation could be categorized as collaborative or shared leadership were eligible for analysis. The authors identified 34 documents from 18 countries that met the eligibility criteria. Studies with shared leadership typically used a comprehensive community action cycle, whereas studies characterized as collaborative showed clear emphasis on collective action but did not undergo an initial process of community dialogue. The review concluded that programs working collaboratively or achieving shared leadership with a community can lead to behavior change and cost-effective sustained transformation to improve critical health behaviors and reduce poor health outcomes in low- and middle-income countries. Overall, community engagement is an understudied component of improving child outcomes. PMID:25207448

Farnsworth, S. Katherine; Böse, Kirsten; Fajobi, Olaoluwa; Souza, Patricia Portela; Peniston, Anne; Davidson, Leslie L.; Griffiths, Marcia; Hodgins, Stephen

2014-01-01

325

The Mitochondrion-Located Protein OsB12D1 Enhances Flooding Tolerance during Seed Germination and Early Seedling Growth in Rice  

PubMed Central

B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo) proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1). OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding. PMID:25089878

He, Dongli; Zhang, Hui; Yang, Pingfang

2014-01-01

326

The mitochondrion-located protein OsB12D1 enhances flooding tolerance during seed germination and early seedling growth in rice.  

PubMed

B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo) proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1). OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding. PMID:25089878

He, Dongli; Zhang, Hui; Yang, Pingfang

2014-01-01

327

Potential Bacillus probiotics enhance bacterial numbers, water quality and growth during early development of white shrimp (Litopenaeus vannamei).  

PubMed

Epidemics of epizootics and occurrence of multiresistant antibiotics of pathogenic bacteria in aquaculture have put forward a development of effective probiotics for the sustainable culture. This study examined the effectiveness of forms of mixed Bacillus probiotics (probiotic A and probiotic B) and mode of probiotic administration on growth, bacterial numbers and water quality during rearing of white shrimp (Litopenaeus vannamei) in two separated experiments: (1) larval stages and (2) postlarval (PL) stages. Forms of Bacillus probiotics and modes of probiotic administration did not affect growth and survival of larval to PL shrimp. The compositions of Bacillus species in probiotic A and probiotic B did not affect growth and survival of larvae. However, postlarvae treated with probiotic B exhibited higher (P<0.05) growth than probiotic A and controls, indicating Bacillus probiotic composition affects the growth of PL shrimp. Total heterotrophic bacteria and Bacillus numbers in larval and PL shrimp or culture water of the treated groups were higher (P<0.05) than in controls. Levels of pH, ammonia and nitrite of the treated shrimp were significantly decreased, compared to the controls. Microencapsulated Bacillus probiotic was effective for rearing of PL L. vannamei. This investigation showed that administration of mixed Bacillus probiotics significantly improved growth and survival of PL shrimp, increased beneficial bacteria in shrimp and culture water and enhanced water quality for the levels of pH, ammonia and nitrite of culture water. PMID:22595137

Nimrat, Subuntith; Suksawat, Sunisa; Boonthai, Traimat; Vuthiphandchai, Verapong

2012-10-12

328

Early Embryogenesis-Specific Expression of the Rice Transposon Ping Enhances Amplification of the MITE mPing  

PubMed Central

Miniature inverted-repeat transposable elements (MITEs) are numerically predominant transposable elements in the rice genome, and their activities have influenced the evolution of genes. Very little is known about how MITEs can rapidly amplify to thousands in the genome. The rice MITE mPing is quiescent in most cultivars under natural growth conditions, although it is activated by various stresses, such as tissue culture, gamma-ray irradiation, and high hydrostatic pressure. Exceptionally in the temperate japonica rice strain EG4 (cultivar Gimbozu), mPing has reached over 1000 copies in the genome, and is amplifying owing to its active transposition even under natural growth conditions. Being the only active MITE, mPing in EG4 is an appropriate material to study how MITEs amplify in the genome. Here, we provide important findings regarding the transposition and amplification of mPing in EG4. Transposon display of mPing using various tissues of a single EG4 plant revealed that most de novo mPing insertions arise in embryogenesis during the period from 3 to 5 days after pollination (DAP), and a large majority of these insertions are transmissible to the next generation. Locus-specific PCR showed that mPing excisions and insertions arose at the same time (3 to 5 DAP). Moreover, expression analysis and in situ hybridization analysis revealed that Ping, an autonomous partner for mPing, was markedly up-regulated in the 3 DAP embryo of EG4, whereas such up-regulation of Ping was not observed in the mPing-inactive cultivar Nipponbare. These results demonstrate that the early embryogenesis-specific expression of Ping is responsible for the successful amplification of mPing in EG4. This study helps not only to elucidate the whole mechanism of mPing amplification but also to further understand the contribution of MITEs to genome evolution. PMID:24921928

Teramoto, Shota; Tsukiyama, Takuji; Okumoto, Yutaka; Tanisaka, Takatoshi

2014-01-01

329

Growth performance of early-weaned pigs is enhanced by feeding epidermal growth factor-expressing Lactococcus lactis fermentation product.  

PubMed

We have previously generated epidermal growth factor expressing Lactococcus lactis (EGF-LL) using bioengineering approach, and shown that feeding newly-weaned piglets EGF-LL improves digestive function. To address concerns over the use of genetically modified organisms (GMO), the objective of the current study was to investigate the effect of feeding the EGF-LL fermentation product, after removal of the genetically modified EGF-LL, on growth performance and intestine development of newly-weaned piglets. One hundred and twenty newly-weaned piglets were fed ad libitum according to a 2-phase feeding program. Four pens were assigned to each of three treatments: (1) complete EGF-LL fermentation product (Ferm), (2) supernatant of EGF-LL fermentation product, after removal of EGF-LL (Supern), or (3) blank M17GE media (Control). EGF-LL or its fermented supernatant was administrated to piglets in the first 3 weeks post-weaning; their growth performance was monitored throughout treatment, and for the following week. Daily body weight gain (254.8g vs. 200.5g) and Gain:Feed (0.541kg/kg vs. 0.454kg/kg) of pigs on the Supern group were significantly improved compared to that of Control, although no difference was observed between the Ferm and Control pigs. Intestinal sucrase activity was increased in Supern- compared to Control group (166.3±62.1 vs. 81.4±56.5nmol glucose released/mg protein; P<0.05). The lack of growth response with Ferm pigs may be attributed to an overload of bacteria (daily dose included 4.56×10(10)CFU/kg BW/day EGF-LL). These results suggest that GMO-free EGF-LL fermentation product is effective in increasing growth performance of early-weaned piglets. PMID:24445174

Bedford, Andrea; Huynh, Evanna; Fu, Molei; Zhu, Cuilan; Wey, Doug; de Lange, Cornelis; Li, Julang

2014-03-10

330

Renal artery aneurysms.  

PubMed

A renal artery aneurysm is defined as a dilated segment of renal artery that exceeds twice the diameter of a normal renal artery. Although rare, the diagnosis and incidence of this entity have been steadily increasing due to the routine use of cross-sectional imaging. In certain cases, renal artery aneurysms may be clinically important and potentially lethal. However, knowledge of their occurrence, their natural history, and their prognosis with or without treatment is still limited. This article aims to review the recent literature concerning renal artery aneurysms, with special consideration given to physiopathology, indications for treatment, different technical options, post-procedure complications and treatment outcomes. PMID:24363127

González, J; Esteban, M; Andrés, G; Linares, E; Martínez-Salamanca, J I

2014-01-01

331

Jet pump assisted artery  

NASA Technical Reports Server (NTRS)

A procedure for priming an arterial heat pump is reported; the procedure also has a means for maintaining the pump in a primed state. This concept utilizes a capillary driven jet pump to create the necessary suction to fill the artery. Basically, the jet pump consists of a venturi or nozzle-diffuser type constriction in the vapor passage. The throat of this venturi is connected to the artery. Thus vapor, gas, liquid, or a combination of the above is pumped continuously out of the artery. As a result, the artery is always filled with liquid and an adequate supply of working fluid is provided to the evaporator of the heat pipe.

1975-01-01

332

External artery heat pipe  

NASA Technical Reports Server (NTRS)

An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)

1989-01-01

333

Selective Enhancing Effect of Early Mitotic Inhibitor 1 (Emi1) Depletion on the Sensitivity of Doxorubicin or X-ray Treatment in Human Cancer Cells*  

PubMed Central

Chemotherapy and radiation in addition to surgery has proven useful in a number of different cancer types, but the effectiveness in normal tissue cannot be avoided in these therapies. To improve the effectiveness of these therapies selectively in cancer tissue is important for avoiding side effects. Early mitotic inhibitor 1 (Emi1) is known to have the function to inhibit anaphase-promoting complex/cyclosome ubiquitin ligase complex, which ubiquitylates the cell cycle-related proteins. It recently has been shown that Emi1 knockdown prevents transition from S to G2 phase by down-regulating geminin via anaphase-promoting complex/cyclosome activation. At present, anticancer drugs for targeting DNA synthesis to interfere with rapidly dividing cells commonly are used. As Emi1 depletion interferes with completion of DNA synthesis in cancer cells, we thought that Emi1 knockdown might enhance the sensitivity for anticancer agents. Here, we confirmed that Emi1 siRNA induced polyploidy for preventing transition from S to G2 phase in several cancer cell lines. Then, we treated Emi1 depleted cells with doxorubicin. Interestingly, increased apoptotic cells were observed after doxorubicin treatment in Emi1 siRNA-treated cancer cells. In addition, Emi1 depletion enhanced the sensitivity of x-ray irradiation in cancer cells. Importantly, synergistic effect of Emi1 knockdown in these combination therapies was not observed in normal cells. These results suggest that Emi1 siRNA can be a useful tool for enhancing of sensitivity of cancer cells to anticancer reagents and radiation. PMID:23645673

Shimizu, Natsumi; Nakajima, Nakako Izumi; Tsunematsu, Takaaki; Ogawa, Ikuko; Kawai, Hidehiko; Hirayama, Ryoichi; Fujimori, Akira; Yamada, Akiko; Okayasu, Ryuichi; Ishimaru, Naozumi; Takata, Takashi; Kudo, Yasusei

2013-01-01

334

TGF-ß1 Enhances the BMP-2-Induced Chondrogenesis of Bovine Synovial Explants and Arrests Downstream Differentiation at an Early Stage of Hypertrophy  

PubMed Central

Background Synovial explants furnish an in-situ population of mesenchymal stem cells for the repair of articular cartilage. Although bone morphogenetic protein 2 (BMP-2) induces the chondrogenesis of bovine synovial explants, the cartilage formed is neither homogeneously distributed nor of an exclusively hyaline type. Furthermore, the downstream differentiation of chondrocytes proceeds to the stage of terminal hypertrophy, which is inextricably coupled with undesired matrix mineralization. With a view to optimizing BMP-2-induced chondrogenesis, the modulating influences of fibroblast growth factor 2 (FGF-2) and transforming growth factor beta 1 (TGF-ß1) were investigated. Methodology/Principal Findings Explants of bovine calf metacarpal synovium were exposed to BMP-2 (200 ng/ml) for 4 (or 6) weeks. FGF-2 (10 ng/ml) or TGF-ß1 (10 ng/ml) was introduced at the onset of incubation and was present either during the first week of culturing alone or throughout its entire course. FGF-2 enhanced the BMP-2-induced increase in metachromatic staining for glycosaminoglycans (GAGs) only when it was present during the first week of culturing alone. TGF-ß1 enhanced not only the BMP-2-induced increase in metachromasia (to a greater degree than FGF-2), but also the biochemically-assayed accumulation of GAGs, when it was present throughout the entire culturing period; in addition, it arrested the downstream differentiation of cells at an early stage of hypertrophy. These findings were corroborated by an analysis of the gene- and protein-expression levels of key cartilaginous markers and by an estimation of individual cell volume. Conclusions/Significance TGF-ß1 enhances the BMP-2-induced chondrogenesis of bovine synovial explants, improves the hyaline-like properties of the neocartilage, and arrests the downstream differentiation of cells at an early stage of hypertrophy. With the prospect of engineering a mature, truly articular type of cartilage in the context of clinical repair, our findings will be of importance in fine-tuning the stimulation protocol for the optimal chondrogenic differentiation of synovial explants. PMID:23301025

Shintani, Nahoko; Siebenrock, Klaus A.; Hunziker, Ernst B.

2013-01-01

335

Two genetically and molecularly distinct functions involved in early neurogenesis reside within the Enhancer of split locus of Drosophila melanogaster.  

PubMed

Molecular correlation of the genetic aspects of the function of the neurogenic gene Enhancer of split [E(spl)] has previously been hampered by the densely transcribed nature of the chromosomal region within which it resides. We present data indicating that two distinct molecular species contribute to E(spl) function. Analysis of new E(spl) alleles has allowed us to define two complementing functions within the locus. Subsequent phenotypic analysis of different E(spl) deficiencies combined with P element-transformed constructs has demonstrated that these two functions correspond to: (1) a family of helix-loop-helix (HLH) protein-encoding genes and (2) the single copy gene E(spl) m9/10, whose product shares homology with G-protein beta subunits. The zygotically active E(spl) HLH genes can, at least partially, substitute for one another's functions and their total copy number determines the activity of the locus. E(spl) m9/10 acts synergistically with the E(spl) HLH genes and other neurogenic genes in the process of neurogenesis. The maternal component of E(spl) m9/10 has the most pronounced effect in neurogenesis, while its zygotic component is predominantly required during postembryonic development. The lethality of trans-heterozygotes of null E(spl) deficiency alleles with a strong Delta point mutation is a result of the concomitant reduction in activity of both E(spl) HLH and m9/10 functions. Immunocytochemical localization of the E(spl) m9/10 protein has revealed that it is a ubiquitously distributed nuclear component in embryonic, larval and imaginal tissues. PMID:1752423

Delidakis, C; Preiss, A; Hartley, D A; Artavanis-Tsakonas, S

1991-11-01

336

Angioplasty and stent placement - peripheral arteries - discharge  

MedlinePLUS

Percutaneous transluminal angioplasty - peripheral artery - discharge; PTA - peripheral artery - discharge; Angioplasty - peripheral artery - discharge; Balloon angioplasty - periperhal artiery - discharge

337

Primary leiomyosarcoma of the pulmonary artery: a diagnostic dilemma.  

PubMed

Primary leiomyosarcoma of the pulmonary artery is a rare malignancy arising from the multipotential mesenchymal cell of the intima of the pulmonary artery. Due to its rarity and nonspecific clinical symptoms, the correct diagnosis and proper management are often delayed. Furthermore, it is frequently misdiagnosed as pulmonary embolism, mediastinal mass, pulmonary stenosis and lung cancer. Therefore, it is important to consider primary leiomyosarcoma of the pulmonary artery a possibility when a persistent filling defect is present in the pulmonary artery and there is no response to optimal anticoagulation treatment. Radiologic findings such as a unilateral mass continuously filling the pulmonary artery, inhomogenous enhancement, vascular distension, extravascular invasion into adjacent structure or uptake in the area of tumor on the FDG-PET can be helpful when differentiating pulmonary artery sarcoma (PAS) from chronic thromboembolism. PMID:12727062

Kim, Jin-Hwan; Gutierrez, Fernando R; Lee, Edward Y; Semenkovich, Janice; Bae, Kyongtae T; Ylagan, Lourdes R

2003-01-01

338

Bilateral vertebral artery stenosis present with vertigo  

PubMed Central

Of ischaemic stroke patients, about 25% rise from the posterior or vertebrobasilar system. The ischaemia of vertebral arteries may emerge for different vascular pathological reasons, at different localisations and with different clinical findings. Despite its low morbidity and mortality risk, early diagnosis and treatment is of importance. Vertebrobasilar ischaemia symptoms can be observed clinically such as vertigo, tinnitus, double vision, headache, hypokinesis and hearing disorders, etc. In this article, a 42-year-old stroke patient case is presented, who applied to the emergency service with vertigo and then, was diagnosed with bilateral vertebral artery stenosis by means of cranial MR angiography. PMID:23376658

Kotan, Dilcan; Sayan, Saadet; Acar, Bilgehan Atilgan; Polat, Pinar

2013-01-01

339

Epidermal growth factor-expressing Lactococcus lactis enhances growth performance of early-weaned pigs fed diets devoid of blood plasma.  

PubMed

The effect of supplementing Lactococcus lactis (L. lactis) that was engineered to express epidermal growth factor (EGF-LL) to early-weaned pigs fed diets with typical levels of blood plasma (5%) or diets without blood plasma [blood plasma was substituted with soybean (Glycine max) meal and fish meal, based on amino acid supply] was examined. A total of 108 weaned piglets (19-26 d of age; mean initial BW 6.58 kg; 9 pigs per pen) were fed ad libitum according to a 2-phase feeding program without growth promoters. Three pens were assigned to each of 4 treatments: i) blood plasma-containing diet with blank bacterial growth medium (BP-Con), ii) blood plasma-containing diet with fermented EGF-LL (BP-EGF), iii) blood plasma-free diet with blank bacterial growth medium (BPF-Con), and iv) blood plasma-free diet with fermented EGF-LL (BPF-EGF). The amount of epidermal growth factor (EGF) was determined in the fermentation product and pigs were allotted 60 ?g EGF/kg BW/d for 3 wk postweaning. There were no differences in overall growth performance between BP-Con and BP-EGF pigs and no differences in overall growth performance between LoCon and BPF-EGF pigs. Pigs fed BPF-EGF showed increased daily BW gain (410 vs. 260 g/d; P < 0.01) and gain:feed (0.67 vs. 0.58; P < 0.05) compared to BPF-Con pigs in wk 3 postweaning; this was comparable to values for the BP-Con group (400 g/d and 0.64). These results indicate that supplementation with EGF-LL can be effective in enhancing the performance of early-weaned piglets fed a low complexity diet and reduces the need for feeding high-quality animal proteins and antibiotics. PMID:23365266

Bedford, A; Li, Z; Li, M; Ji, S; Liu, W; Huai, Y; de Lange, C F M; Li, J

2012-12-01

340

Assessment of the Early Effects of 5,6-Dimethylxanthenone-4-Acetic Acid Using Macromolecular Contrast Media-Enhanced Magnetic Resonance Imaging: Ectopic Versus Orthotopic Tumors  

SciTech Connect

Purpose: To investigate the early effects of a vascular disrupting agent (VDA) in ectopic and orthotopic tumors by using macromolecular contrast media (MMCM)-enhanced magnetic resonance imaging (MMCM-MRI). Methods and Materials: The MMCM-MRI of ectopic and orthotopic MCA205 murine fibrosarcomas was performed using the intravascular contrast agent albumin-(gadopentetate dimeglumine){sub 35}. Change in longitudinal relaxation rate ({delta}R1) was measured 24 hours after treatment with 5,6-dimethylxanthenone-4-acetic acid (DMXAA; 30 mg/kg) and used to compute tumor vascular volume and permeability. Correlative histologic and immunohistochemical evaluation was carried out, along with measurement of tumor necrosis factor {alpha} and vascular endothelial growth factor levels in whole tumor extracts using the enzyme-linked immunosorbent assay. Results: Orthotopic tumors showed higher vascular volume (p < 0.05) than ectopic tumors before treatment. Twenty-four hours after DMXAA treatment, a significant (p < 0.0001), but differential, decrease in {delta}R1 (70% in ectopic and 50% in orthotopic tumors) was observed compared with baseline estimates. Consistent with this observation, greater levels of tumor necrosis factor {alpha}, an important mediator of the antivascular activity of DMXAA, were measured in ectopic tumors 3 hours posttreatment compared with orthotopic tumors (p < 0.05). Immunohistochemical (CD31) and histologic (hematoxylin and eosin) sections of ectopic and orthotopic tumors showed highly tumor-selective vascular damage after treatment with the presence of viable surrounding normal tissue. Conclusions: The MMCM-MRI provided early quantitative estimates of change in tumor perfusion after VDA treatment that showed good correlation with cytokine induction. Differences in the response of ectopic and orthotopic tumors highlight the influence of the host microenvironment in modulating the activity of VDAs.

Seshadri, Mukund [Preclinical Imaging Resource, Roswell Park Cancer Institute, Buffalo, NY (United States); Department of Cancer Biology, Roswell Park Cancer Institute, Buffalo, NY (United States)], E-mail: mukund.seshadri@roswellpark.org; Bellnier, David A. [Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY (United States); Cheney, Richard T. [Department of Pathology, Roswell Park Cancer Institute, Buffalo, NY (United States)

2008-11-15

341

Delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC) Shows No Change in Cartilage Structural Composition after Viscosupplementation in Patients with Early-Stage Knee Osteoarthritis  

PubMed Central

Introduction Viscosupplementation with hyaluronic acid (HA) of osteoarthritic (OA) knee joints has a well-established positive effect on clinical symptoms. This effect, however, is only temporary and the working mechanism of HA injections is not clear. It was suggested that HA might have disease modifying properties because of its beneficial effect on cartilage sulphated glycosaminoglycan (sGAG) content. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is a highly reproducible, non-invasive surrogate measure for sGAG content and hence composition of cartilage. The aim of this study was to assess whether improvement in cartilage structural composition is detected using dGEMRIC 14 weeks after 3 weekly injections with HA in patients with early-stage knee OA. Methods In 20 early-stage knee OA patients (KLG I-II), 3D dGEMRIC at 3T was acquired before and 14 weeks after 3 weekly injections with HA. To evaluate patient symptoms, the knee injury and osteoarthritis outcome score (KOOS) and a numeric rating scale (NRS) for pain were recorded. To evaluate cartilage composition, six cartilage regions in the knee were analyzed on dGEMRIC. Outcomes of dGEMRIC, KOOS and NRS before and after HA were compared using paired t-testing. Since we performed multiple t-tests, we applied a Bonferroni-Holm correction to determine statistical significance for these analyses. Results All KOOS subscales (‘pain’, ‘symptoms’, ‘daily activities’, ‘sports’ and ’quality of life’) and the NRS pain improved significantly 14 weeks after Viscosupplementation with HA. Outcomes of dGEMRIC did not change significantly after HA compared to baseline in any of the cartilage regions analyzed in the knee. Conclusions Our results confirm previous findings reported in the literature, showing persisting improvement in symptomatic outcome measures in early-stage knee OA patients 14 weeks after Viscosupplementation. Outcomes of dGEMRIC, however, did not change after Viscosupplementation, indicating no change in cartilage structural composition as an explanation for the improvement of clinical symptoms. PMID:24223194

van Tiel, Jasper; Reijman, Max; Bos, Pieter K.; Hermans, Job; van Buul, Gerben M.; Bron, Esther E.; Klein, Stefan; Verhaar, Jan A. N.; Krestin, Gabriel P.; Bierma-Zeinstra, Sita M. A.; Weinans, Harrie; Kotek, Gyula; Oei, Edwin H. G.

2013-01-01

342

Enhancement of cell ingrowth, proliferation, and early differentiation in a three-dimensional silicon carbide scaffold using low-intensity pulsed ultrasound.  

PubMed

Concerns over the use of autografts or allografts have necessitated the development of biomaterials for bone regeneration. Various studies have been performed to optimize the cultivation of osteogenic cells using osteoconductive porous scaffolds. The aim of this study was to evaluate the osteogenic efficiency of bone cell ingrowth, proliferation, and early differentiation in a silicon carbide (SiC) porous ceramic scaffold promoted with low-intensity pulsed ultrasound. MC3T3-E1 mouse preosteoblasts were seeded onto scaffolds and cultured for 4 and 7 days with daily of 20-min ultrasound treatment. The cells were evaluated for cell attachment, morphology, viability, ingrowth depth, volumetric proliferation, and early differentiation. After 4 and 7 days of culture and ultrasound exposure, the cell density was higher in the ultrasound-treated group compared with the sham-treated group on SiC scaffolds. The cell ingrowth depths inside the SiC scaffolds were 149.2±27.3??m at 1 day, 310.1±12.6??m for the ultrasound-treated group and 248.0±19.7??m for the sham control at 4 days, and 359.6±18.5??m for the ultrasound-treated group and 280.0±17.7??m for the sham control at 7 days. They were significantly increased, that is, 25% (p=0.0029) and 28% (p=0.0008) increase, respectively, with ultrasound radiation force as compared with those in sham control at 4 and 7 days postseeding. The dsDNA contents were 583.5±19.1?ng/scaffold at 1 day, 2749.9±99.9?ng/scaffold for the ultrasound-treated group and 2514.9±114.7?ng/scaffold for the sham control at 4 days, and 3582.3±325.3?ng/scaffold for the ultrasound-treated group and 2825.7±134.3?ng/scaffold for the sham control at 7 days. There was a significant difference in the dsDNA content between the ultrasound- and sham-treated groups at 4 and 7 days. The ultrasound-treated group with the SiC construct showed a 9% (p=0.00029) and 27% (p=0.00017) increase in the average dsDNA content at 4 and 7 days over the sham control group, respectively. Alkaline phosphatase activity was significantly increased by the treatment of ultrasound at 4 (p=0.012) and 7 days (p=0.035). These results suggested that ultrasound treatment with low-intensity acoustic energy facilitated the cellular ingrowth and enhanced the proliferation and early differentiation of osteoblasts in SiC scaffolds. PMID:24935158

Wu, Lin; Lin, Liangjun; Qin, Yi-Xian

2015-01-01

343

About Peripheral Artery Disease (PAD)  

MedlinePLUS

About Peripheral Artery Disease (PAD) Updated:Sep 15,2014 Peripheral artery disease (PAD) is a narrowing of the peripheral arteries to ... was last reviewed on 8/05/2014. Peripheral Artery Disease • Home • About Peripheral Artery Disease (PAD) • Why ...

344

Endothelial nitric oxide synthase-enhancing G-protein coupled receptor antagonist inhibits pulmonary artery hypertension by endothelin-1-dependent and endothelin-1-independent pathways in a monocrotaline model.  

PubMed

This study investigates whether endothelin-1 (ET-1) mediates monocrotaline (MCT)-induced pulmonary artery hypertension (PAH) and right ventricular hypertrophy (RVH), and if so, whether the G-protein coupled receptor antagonist KMUP-1 (7-{2-[4-(2-chlorobenzene)piperazinyl]ethyl}-1,3-dimethylxanthine) inhibits ET-1-mediated PA constriction and the aforementioned pathological changes. In a chronic rat model, intraperitoneal MCT (60 mg/kg) induced PAH and increased PA medial wall thickening and RV/left ventricle + septum weight ratio on Day 21 after MCT injection. Treatment with sublingual KMUP-1 (2.5 mg/kg/day) for 21 days prevented these changes and restored vascular endothelial nitric oxide synthase (eNOS) immunohistochemical staining of lung tissues. Western blotting analysis demonstrated that KMUP-1 enhanced eNOS, soluble guanylate cyclase, and protein kinase G levels, and reduced ET-1 expression and inactivated Rho kinase II (ROCKII) in MCT-treated lung tissue over long-term administration. In MCT-treated rats, KMUP-1 decreased plasma ET-1 on Day 21. KMUP-1 (3.6 mg/kg) maximally appeared at 0.25 hours in the plasma and declined to basal levels within 24 hours after sublingual administration. In isolated PA of MCT-treated rats, compared with control and pretreatment with l-NG-nitroarginine methyl ester (100 ?M), KMUP-1 (0.1-100 ?M) inhibited ET-1 (0.01 ?M)-induced vasoconstriction. Endothelium-denuded PA sustained higher contractility in the presence of KMUP-1. In a 24-hour culture of smooth muscle cells (i.e., PA smooth muscle cells or PASMCs), KMUP-1 (0.1-10 ?M) inhibited RhoA- and ET-1-induced RhoA activation. KMUP-1 prevented MCT-induced PAH, PA wall thickening, and RVH by enhancing eNOS and suppressing ET-1/ROCKII expression. In vitro, KMUP-1 inhibited ET-1-induced PA constriction and ET-1-dependent/independent RhoA activation of PASMCs. In summary, KMUP-1 attenuates ET-1-induced/ET-1-mediated PA constriction, and could thus aid in the treatment of PAH caused by MCT. PMID:24835346

Liu, Chung-Pin; Dai, Zen-Kong; Huang, Chein-Heng; Yeh, Jwu-Lai; Wu, Bin-Nan; Wu, Jiunn-Ren; Chen, Ing-Jun

2014-06-01

345

Celiac Artery Compression Syndrome  

PubMed Central

Celiac artery compression syndrome is a rare disorder characterized by episodic abdominal pain and weight loss. It is the result of external compression of celiac artery by the median arcuate ligament. We present a case of celiac artery compression syndrome in a 57-year-old male with severe postprandial abdominal pain and 30-pound weight loss. The patient eventually responded well to surgical division of the median arcuate ligament by laparoscopy. PMID:23653867

Muqeetadnan, Mohammed; Amer, Syed; Rahman, Ambreen; Nusrat, Salman; Hassan, Syed

2013-01-01

346

Absent pulmonary artery  

Microsoft Academic Search

Summary  Cardiac catheterization was performed in nine patients with unilateral absence of a pulmonary artery. Aortography revealed\\u000a a diverticulum of the innominate artery in five of six patients in whom the aortic arch and absent pulmonary artery were on\\u000a opposite sides. It is suggested that the diverticulum indicates fetal systemic blood supply to the affected lung through the\\u000a distal part of

Joachim R. Pfefferkorn; Hermann Löser; Gabriele Pech; Robert Toussaint; Fritz Hilgenberg

1982-01-01

347

Anomalous left coronary artery from the pulmonary artery  

MedlinePLUS

... damages the heart in babies with ALCAPA. The low blood pressure in the pulmonary artery causes blood from the abnormal left coronary artery to flow toward the pulmonary artery instead of toward the ...

348

Elastomeric PGS Scaffolds in Arterial Tissue Engineering  

PubMed Central

Cardiovascular disease is one of the leading cause of mortality in the US and especially, coronary artery disease increases with an aging population and increasing obesity1. Currently, bypass surgery using autologous vessels, allografts, and synthetic grafts are known as a commonly used for arterial substitutes2. However, these grafts have limited applications when an inner diameter of arteries is less than 6 mm due to low availability, thrombotic complications, compliance mismatch, and late intimal hyperplasia3,4. To overcome these limitations, tissue engineering has been successfully applied as a promising alternative to develop small-diameter arterial constructs that are nonthrombogenic, robust, and compliant. Several previous studies have developed small-diameter arterial constructs with tri-lamellar structure, excellent mechanical properties and burst pressure comparable to native arteries5,6. While high tensile strength and burst pressure by increasing collagen production from a rigid material or cell sheet scaffold, these constructs still had low elastin production and compliance, which is a major problem to cause graft failure after implantation. Considering these issues, we hypothesized that an elastometric biomaterial combined with mechanical conditioning would provide elasticity and conduct mechanical signals more efficiently to vascular cells, which increase extracellular matrix production and support cellular orientation. The objective of this report is to introduce a fabrication technique of porous tubular scaffolds and a dynamic mechanical conditioning for applying them to arterial tissue engineering. We used a biodegradable elastomer, poly (glycerol sebacate) (PGS)7 for fabricating porous tubular scaffolds from the salt fusion method. Adult primary baboon smooth muscle cells (SMCs) were seeded on the lumen of scaffolds, which cultured in our designed pulsatile flow bioreactor for 3 weeks. PGS scaffolds had consistent thickness and randomly distributed macro- and micro-pores. Mechanical conditioning from pulsatile flow bioreactor supported SMC orientation and enhanced ECM production in scaffolds. These results suggest that elastomeric scaffolds and mechanical conditioning of bioreactor culture may be a promising method for arterial tissue engineering. PMID:21505410

Lee, Kee-Won; Wang, Yadong

2011-01-01

349

Arterial waveform analysis.  

PubMed

The bedside measurement of continuous arterial pressure values from waveform analysis has been routinely available via indwelling arterial catheterization for >50 years. Invasive blood pressure monitoring has been utilized in critically ill patients, in both the operating room and critical care units, to facilitate rapid diagnoses of cardiovascular insufficiency and monitor response to treatments aimed at correcting abnormalities before the consequences of either hypo- or hypertension are seen. Minimally invasive techniques to estimate cardiac output (CO) have gained increased appeal. This has led to the increased interest in arterial waveform analysis to provide this important information, as it is measured continuously in many operating rooms and intensive care units. Arterial waveform analysis also allows for the calculation of many so-called derived parameters intrinsically created by this pulse pressure profile. These include estimates of left ventricular stroke volume (SV), CO, vascular resistance, and during positive-pressure breathing, SV variation, and pulse pressure variation. This article focuses on the principles of arterial waveform analysis and their determinants, components of the arterial system, and arterial pulse contour. It will also address the advantage of measuring real-time CO by the arterial waveform and the benefits to measuring SV variation. Arterial waveform analysis has gained a large interest in the overall assessment and management of the critically ill and those at a risk of hemodynamic deterioration. PMID:25480767

Esper, Stephen A; Pinsky, Michael R

2014-12-01

350

Conformable amplified lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring  

NASA Astrophysics Data System (ADS)

The ability to measure subtle changes in arterial pressure using devices mounted on the skin can be valuable for monitoring vital signs in emergency care, detecting the early onset of cardiovascular disease and continuously assessing health status. Conventional technologies are well suited for use in traditional clinical settings, but cannot be easily adapted for sustained use during daily activities. Here we introduce a conformal device that avoids these limitations. Ultrathin inorganic piezoelectric and semiconductor materials on elastomer substrates enable amplified, low hysteresis measurements of pressure on the skin, with high levels of sensitivity (~0.005?Pa) and fast response times (~0.1?ms). Experimental and theoretical studies reveal enhanced piezoelectric responses in lead zirconate titanate that follow from integration on soft supports as well as engineering behaviours of the associated devices. Calibrated measurements of pressure variations of blood flow in near-surface arteries demonstrate capabilities for measuring radial artery augmentation index and pulse pressure velocity.

Dagdeviren, Canan; Su, Yewang; Joe, Pauline; Yona, Raissa; Liu, Yuhao; Kim, Yun-Soung; Huang, Yongan; Damadoran, Anoop R.; Xia, Jing; Martin, Lane W.; Huang, Yonggang; Rogers, John A.

2014-08-01

351

Value of F-18 FDG hybrid camera PET and MRI in early takayasu aortitis.  

PubMed

Takayasu aortitis (TA) is a chronic inflammatory and fibrotic vasculitis of large- and medium-sized arteries. Early stages of the disease show a panarteritis and inflammatory wall thickening of the aorta and its branches, whereas advanced (fibrotic) stages comprise stenosis, aneurismatic transformation and occlusion. Magnetic resonance imaging visualises early-stage disease with high accuracy and is considered to be the method of choice in the diagnosis of TA. The aim of this article is the detailed comparison of FDG-PET performed with a hybrid camera and MR imaging in five patients with early TA. Five patients (median age 60 years) were enrolled during an ongoing prospective study on [18F]2'-deoxy-2-fluoro-D-glucose (FDG) hybrid camera PET in patients with fever of unknown origin (FUO). These patients underwent MR imaging after establishing the diagnosis of TA. Abnormal FDG uptake in the wall of the aorta was noted in all patients. The bracheocephalic artery and the common carotid arteries were visualized in 3 cases. Increased uptake of the subclavian artery was found in 3 patients and in 4 patients pathological uptake was noted in the ilio-femoral vessels. Of 34 vascular regions studied, 26 (76%) showed elevated FDG uptake. On transversal MR images vessel wall thickening and contrast enhancement of the thoracic aorta was found in 4 patients (ascending aorta/aortic arch: n=2; descending aorta: n=3; abdominal aorta: n=1). Additionally, vessel wall pathologies of the subclavian and the common carotid arteries could be shown in 1 patient and in another patient in the ilio-femoral arteries. No abnormalities were found using contrast-enhanced MR angiography. Of 28 vascular regions studied, 9 (32%) showed vasculitis on MRI. The FDG-PET is a suitable whole-body screening method in the primary diagnosis of early TA, especially in those cases with early disease that present with uncharacteristic symptoms such as FUO. Both MRI and MRA remain indispensable in the exact determination of the pathomorphological changes and in the documentation of complications such as stenosis, aneurismatic transformation and occlusion. PMID:12599007

Meller, J; Grabbe, E; Becker, W; Vosshenrich, R

2003-02-01

352

Spontaneous Rupture of the Omental Artery Treated by Transcatheter Arterial Embolization  

PubMed Central

Intra-abdominal hemorrhage caused by omental artery rupture is a rare condition. There are few reports on the treatment of omental artery rupture with only transcatheter arterial embolization (TAE). A 27-year-old man presented to our emergency room with upper abdominal pain that suddenly occurred during sleep. Abdominal computed tomography (CT) revealed fluid collection in the peritoneal cavity and a left subphrenic hematoma with extravasation. Celiac angiography revealed extravasation from the omental artery, which arose from the proximal left gastroepiploic artery. A microcatheter was advanced into the left gastroepiploic artery and around the culprit artery bifurcation, which was embolized by inserting coils. The postoperative course was uneventful without worsening of anemia or abdominal symptoms. The patient was discharged after the absence of extravasation was confirmed by contrast-enhanced CT. Although surgical therapy has often been performed for omental bleeding, TAE, which is less invasive and has the advantage of simultaneous diagnosis and treatment, should be attempted as the first-choice therapy. PMID:23316406

Matsuoka, Yujiro; Yasutake, Tsuyoshi; Abe, Hiroyuki; Sugiyama, Kazuhiro; Oyama, Kazuyuki

2012-01-01

353

Enhanced biological activity by an anticyclonic warm eddy during early spring in the East Sea (Japan Sea) detected by the geostationary ocean color satellite  

NASA Astrophysics Data System (ADS)

The high primary production enhanced by anticyclonic eddies and hourly variation pattern in the productivity during the spring season in the East Sea were first investigated using the first Korean Geostationary Ocean Color Imager (GOCI). Even though the stratification for a seasonal spring bloom is not well developed in the water column in early April in the East Sea, a physical upward water flux movement at the periphery of the anticyclonic eddies could remain the phytoplankton in euphotic zone to sustain high chlorophyll-a concentration conditions in the Ulleung Basin. At this time, nutrients were no major controlling factor for phytoplankton growth since concentrations of major nutrients (nitrate, silicate, and phosphate) were relatively high in the observed eddy sites based on the observation data from the Korean Oceanographic Data Center (KODC). The estimated mixed layer depth (MLD) significantly shallower at the periphery supports for this mechanism. The hourly primary productivity estimation based on a Carbon-based Productivity Model (CbPM) provides a bimodal pattern along the time especially in L1 with an approximately one order magnitude difference between the lowest and highest values of productivities on 5 April, 2011. Potential possibilities for this large discrepancy in the hourly productivity and some thoughts on a short time in situ incubation method were discussed.

Lim, Jae-Hyun; Son, Seunghyun; Park, Jung-Woo; Kwak, Jung Hyun; Kang, Chang-Keun; Son, Young Baek; Kwon, Jung-No; Lee, Sang Heon

2012-09-01

354

Based on surface-enhanced Raman spectroscopy analysis of serum albumin in different stages of liver disease for early screening primary liver cancer  

NASA Astrophysics Data System (ADS)

Despite the introduction of high-technology methods of detection and diagnosis, screening of primary liver cancer (PLC) remains imperfect. To diagnosis PLC earlier, Surface-enhanced Raman spectroscopy (SERS) coupled with cellulose-acetate membrane electrophoresis were introduced to separate human serum albumin and SERS spectra. Three groups (15 normal persons' samples, 17 hepatitis/cirrhosis samples, 15 cases of PLC) of serum albumin were tested. Silver colloid was used to obtain SERS spectra of human serum albumin. Principal component analysis (PCA) and linear discriminant analysis (LDA) were also employed for statistical analysis. The mean Raman spectra of three groups and the difference spectra of any two suggested that the albumin has changed in liver patients. Compared to normal groups, some Raman peaks have shifted or even disappeared in hepatitis/cirrhosis and PLCs groups. The sensitivity and specificity between PLCs and normal groups is 80% and 93.3%. Among hepatitis/cirrhosis and normal groups, the sensitivity is 88.2% and specificity is also 93.3%. Besides, the sensitivity and specificity between PLCs and hepatitis/cirrhosis groups is 86.7% and 76.5%. All the above data and results indicated that early screening of PLC is potential by SERS in different stages of liver disease before cancer occurs.

Liao, Fadian; Ruan, Qiuyong; Lin, Juqiang; Lin, Jinyong; Zeng, Yongyi; Li, Ling; Huang, Zufang; Liu, Nenrong; Chen, Rong

2014-09-01

355

Neurofibromatosis Type 1: Transcatheter Arterial Embolization for Ruptured Occipital Arterial Aneurysms  

SciTech Connect

Two cases of ruptured aneurysms in the posterior cervical regions associated with type-1 neurofibromatosis treated by transcatheter embolization are reported. Patients presented with acute onset of swelling and pain in the affected areas. Emergently performed contrast-enhanced CT demonstrated aneurysms and large hematomas widespread in the posterior cervical regions. Angiography revealed aneurysms and extravasations of the occipital artery. Patients were successfully treated by percutaneous transcatheter arterial microcoil embolization. Transcatheter arterial embolization therapy was found to be an effective method for treating aneurysmal rupture in the posterior cervical regions occurring in association with type-1 neurofibromatosis. A literature review revealed that rupture of an occipital arterial aneurysm, in the setting of neurofibromatosis type 1, has not been reported previously.

Kanematsu, Masayuki; Kato, Hiroki; Kondo, Hiroshi; Goshima, Satoshi; Tsuge, Yusuke; Kojima, Toshiaki; Watanabe, Haruo [Gifu University Hospital, Department of Radiology (Japan)

2011-02-15

356

Measurements of the Longitudinal Movement and the Minute Roughness of the Arterial Wall - New Approaches in Arterial Characterisation  

Microsoft Academic Search

Cardiovascular diseases constitute the major cause of morbidity and mortality in the Western World. To increase our knowledge of cardiovascular diseases, it is important to find methods, preferably non-invasive ones, to study very early manifestations of vascular disease. Changes in the mechanical properties of the arteries can be an early manifestation of vascular disease (2). Moreover, changes in the mechanical

Magnus Cinthio; Åsa Rydén Ahlgren; Hideyuki Hasegawa; Tomas Jansson; Hans W Persson; Kjell Lindström; Hiroshi Kanai

357

Living with Carotid Artery Disease  

MedlinePLUS

... from the NHLBI on Twitter. Living With Carotid Artery Disease If you have carotid artery disease, you can take steps to manage the ... treatment plan, and getting ongoing care. Having carotid artery disease raises your risk of having a stroke . ...

358

[Non-contrast time-resolved magnetic resonance angiography combining high resolution multiple phase echo planar imaging based signal targeting and alternating radiofrequency contrast inherent inflow enhanced multi phase angiography combining spatial resolution echo planar imaging based signal targeting and alternating radiofrequency in intracranial arteries].  

PubMed

Detailed information on anatomy and hemodynamics in cerebrovascular disorders such as AVM and Moyamoya disease is mandatory for defined diagnosis and treatment planning. Arterial spin labeling technique has come to be applied to magnetic resonance angiography (MRA) and perfusion imaging in recent years. However, those non-contrast techniques are mostly limited to single frame images. Recently we have proposed a non-contrast time-resolved MRA technique termed contrast inherent inflow enhanced multi phase angiography combining spatial resolution echo planar imaging based signal targeting and alternating radiofrequency (CINEMA-STAR). CINEMA-STAR can extract the blood flow in the major intracranial arteries at an interval of 70 ms and thus permits us to observe vascular construction in full by preparing MIP images of axial acquisitions with high spatial resolution. This preliminary study demonstrates the usefulness of the CINEMA-STAR technique in evaluating the cerebral vasculature. PMID:23171775

Nakamura, Masanobu; Yoneyama, Masami; Tabuchi, Takashi; Takemura, Atsushi; Obara, Makoto; Sawano, Seishi

2012-01-01

359

Early Algebra, Early Arithmetic  

NSDL National Science Digital Library

This site offers a variety of early algebra resources for teachers in grades 1-6, parents, researchers, policy makers, administrators, and curriculum developers. Site includes early algebra activities, handouts and overheads in PDF format (requires Acrobat Reader), articles, short reviews of articles and books focusing on early math and early algebra, news and events, and more. A valuable source for pre algebra activities in the elementary classroom.

National Science Foundation (NSF)

2007-12-12

360

BLOOD FLOW IN ARTERIES  

Microsoft Academic Search

Bloodflow in arteries is dominated by unsteadyflow phenomena. The cardiovas- cular system is an internal flow loop with multiple branches in which a complex liquid circulates. A nondimensional frequency parameter, the Womersley num- ber, governs the relationship between the unsteady and viscous forces. Normal arterial flow is laminar with secondary flows generated at curves and branches. Thearteriesarelivingorgansthatcanadapttoandchangewiththevaryinghemo- dynamic conditions. In

David N. Ku

1997-01-01

361

Coronary artery disease (image)  

MedlinePLUS

... through these arteries is critical for the heart. Coronary artery disease usually results from the build-up of fatty material and plaque, a condition called atherosclerosis. As the ... blood to the heart can slow or stop, causing chest pain (stable ...

362

Splenic artery aneurysms  

Microsoft Academic Search

The cause of splenic artery aneurysms and the indications for their treatment remain controversial. Splenic artery aneurysms occur more frequently in women and are associated with pregnancy and multiparity. Whether arteriosclerosis is the cause of the aneurysm or is a secondary phenomenon is unknown. Patients not treated do well, especially if the aneurysm is less than 2 cm in diameter.

Victor F. Trastek; Peter C. Pairolero; Philip E. Bernatz

1985-01-01

363

Genetics in Arterial Calcification  

PubMed Central

Artery calcification reflects an admixture of factors such as ectopic osteochondral differentiation with primary host pathological conditions. We review how genetic factors, as identified by human genome-wide association studies, and incomplete correlations with various mouse studies, including knockout and strain analyses, fit into “pieces of the puzzle” in intimal calcification in human atherosclerosis, and artery tunica media calcification in aging, diabetes mellitus, and chronic kidney disease. We also describe in sharp contrast how ENPP1, CD73, and ABCC6 serve as “cogs in a wheel” of arterial calcification. Specifically, each is a minor component in the function of a much larger network of factors that exert balanced effects to promote and suppress arterial calcification. For the network to normally suppress spontaneous arterial calcification, the “cogs” ENPP1, CD73, and ABCC6 must be present and in working order. Monogenic ENPP1, CD73, and ABCC6 deficiencies each drive a molecular pathophysiology of closely related but phenotypically different diseases (generalized arterial calcification of infancy (GACI), pseudoxan-thoma elasticum (PXE) and arterial calcification caused by CD73 deficiency (ACDC)), in which premature onset arterial calcification is a prominent but not the sole feature. PMID:21852556

Rutsch, Frank; Nitschke, Yvonne; Terkeltaub, Robert

2011-01-01

364

Arterial Calcifications in ?-Thalassemia  

Microsoft Academic Search

The purpose of this study was to define the incidence of arterial calcifications in patients with ?-Thalassemia. ?-thalassemia patients have been shown to present a high preva lence of angioid streaks and skin lesions characteristic of pseudoxanthoma elasticum (PXE). Given the fact that vascular involvement in the form of arterial calcifications is also a common manifestation of PXE, the authors

Athanassios Aessopos; Michael Samarkos; Ersi Voskaridou; Dimitris Papaioannou; Maria Tsironi; Emmanuel Kavouklis; George Vaiopoulos; George Stamatelos; Dimitris Loukopoulos

1998-01-01

365

Location of Resistance Arteries  

Microsoft Academic Search

Thickening and narrowing of resistance arteries must, by definition, be key elements in the control of the cardiovascular system. However, the precise location of resistance arteries is difficult to establish. This is due to technical problems related to the small size of the vessels, to the measurement conditions disturbing the hemodynamics, and to the status of the animals while the

Kent L. Christensen; Michael J. Mulvany

2001-01-01

366

Arterial Pressure Analog.  

ERIC Educational Resources Information Center

Describes a simple hydraulic analog which allows students to explore some physical aspects of the cardiovascular system and provides them with a means to visualize and conceptualize these basic principles. Simulates the behavior of arterial pressure in response to changes in heart rate, stroke volume, arterial compliance, and peripheral…

Heusner, A. A.; Tracy, M. L.

1980-01-01

367

Weak Radial Artery Pulse  

PubMed Central

We present an 11year-old boy with a weak right radial pulse, and describe the successful application of vascular ultrasound to identify the ulnar artery dominance and a thin right radial artery with below normal Doppler flow velocity that could explain the discrepancy. The implications of identifying this anomaly are discussed. PMID:22375269

Venugopalan, Poothirikovil; Sivakumar, Puthuval; Ardley, Robert G.; Oates, Crispian

2012-01-01

368

Radial Artery Catheterization  

MedlinePLUS

... because of a blood clot forming in the artery. Blood thinners given during the procedure help to prevent ... in less than 2% of cases. When radial artery occlusion does occur, it generally causes no issue for the hand because there are redundant blood supplies to the hand. Previous Section Next Section ...

369

Short- and long-term outcomes of kidney transplants with multiple renal arteries.  

PubMed Central

OBJECTIVE: The authors determined whether the use of kidney allografts with multiple renal arteries adversely effects post-transplant graft and patient outcome or increases the incidence of vascular and urologic complications. BACKGROUND: Kidney grafts with multiple renal arteries have been associated with an increased incidence of early vascular and urologic complications. Kidney transplants with single versus multiple renal arteries have not been compared in regard to long-term graft and patient outcome or post-transplant incidence of hypertension, acute tubular necrosis, rejection, and late vascular and urologic complications. METHODS: We analyzed 998 adult kidney transplants done from December 1, 1985 through June 30, 1993, in which only the recipient's external or internal iliac artery was used for anastomosis. We divided the study population into 3 groups: Group A-1 renal artery, 1 arterial anastomosis (n = 835), Group B-->1 renal artery, 1 arterial anastomosis (n = 112), Group C-->1 renal artery, > 1 arterial anastomosis (n = 51). We compared the incidence of post-transplant hypertension, acute tubular necrosis, acute rejection, and vascular and urologic complications; mean creatinine levels at 1, 3, and 5 years post-transplant; and patient and graft survival. Univariate and multivariate analyses were done to identify risk factors for vascular complications. RESULTS: We found no significant differences among the three groups for the following variables: post-transplant hypertension, acute tubular necrosis, acute rejection, creatinine levels, early vascular and urologic complications, and graft and patient survival. In kidneys with single arteries, the presence (vs. absence) of an aortic patch and the type of the arterial anastomosis (end-to-end to the hypogastric vs. end-to-side to the external iliac artery) did not have an impact on the incidence of early or late vascular complications. In kidneys with multiple arteries, only the rate of late renal artery stenosis was higher, the rate of early vascular and urologic complications was not different. Our multivariate analysis identified acute tubular necrosis as a risk factor for renal artery and vein thrombosis; graft placement on the left side for arterial thrombosis; and preservation time > or = 24 hours and multiple renal arteries for renal artery stenosis. CONCLUSIONS: Results of kidney transplants using allografts with multiple versus single arteries are similar. Images Figure 1. Figure 2. Figure 3. Figure 5. PMID:7726677

Benedetti, E; Troppmann, C; Gillingham, K; Sutherland, D E; Payne, W D; Dunn, D L; Matas, A J; Najarian, J S; Grussner, R W

1995-01-01

370

3D MR angiographic visualization and artery-vein separation  

NASA Astrophysics Data System (ADS)

The common approach for artery-vein separation applies a presaturation pulse to obtain different image intensity representations in MRA data for arteries and veins. However, when arteries and veins do not run in opposite directions as in the brain, lungs, and heart, this approach fails. This paper presents an image processing approach devised for artery-vein separation. The anatomic separation utilizes fuzzy connected object delineation. The first step of this separation method is the segmentation of the entire vessel structure from the background via absolute connectedness by using scale-based affinity. The second step is to separate artery from vein via relative connectedness. After 'seed' points are specified inside artery and vein in the vessel- only image, the operation is performed in an iterative fashion. The small regions of the bigger aspects of artery and vein are separated in the initial iteration. Further regions are added with the subsequent iterations so that the small aspects of artery and vein are included in alter iterations. Shell rendering is used for 3D display. Combining the strengths of fuzzy connected object definition, object separation, and shell rendering, high- quality volume rendering of vascular information in MRA data has been achieved. MS-325 contrast-enhanced MRA were used to illustrate this approach. Several examples of 3D display of arteries and veins are included to show the considerable promise of this new approach.

Lei, Tianhu; Udupa, Jayaram K.; Saha, Punam K.; Odhner, Dewey

1999-05-01

371

Partial aortic occlusion and cerebral venous steal: venous effects of arterial manipulation in acute stroke.  

PubMed

Acute ischemic stroke therapy emphasizes early arterial clot lysis or removal. Partial aortic occlusion has recently emerged as an alternative hemodynamic approach to augment cerebral perfusion in acute ischemic stroke. The exact mechanism of cerebral flow augmentation with partial aortic occlusion remains unclear and may involve more than simple diversion of arterial blood flow from the lower body to cerebral collateral circulation. The cerebral venous steal hypothesis suggests that even a small increase in tissue pressure in the ischemic area will divert blood flow to surrounding regions with lesser tissue pressures. This may cause no-reflow (absence of flow after restoration of arterial patency) in the ischemic core and "luxury perfusion" in the surrounding regions. Such maldistribution may be reversed with increased venous pressure titrated to avoid changes in intracranial pressure. We propose that partial aortic occlusion enhances perfusion in the brain by offsetting cerebral venous steal. Partial aortic occlusion redistributes blood volume into the upper part of the body, manifested by an increase in central venous pressure. Increased venous pressure recruits the collapsed vascular network and, by eliminating cerebral venous steal, corrects perifocal perfusion maldistribution analogous to positive end-expiratory pressure recruitment of collapsed airways to decrease ventilation/perfusion mismatch in the lungs. PMID:21441149

Pranevicius, Osvaldas; Pranevicius, Mindaugas; Liebeskind, David S

2011-05-01

372

The effect of occult diabetic status and oral glucose intake on brachial artery vasoactivity in patients with peripheral vascular disease 1 Presented at the Annual Meeting of the Military Vascular Society and the Chesapeake Vascular Society, December 5, 1997, Bethesda, MD, USA. 1  

Microsoft Academic Search

Brachial artery vasoactivity is a well known non-invasive method of assessing arterial endothelial function in vivo. Brachial artery vasoactivity has been found to be impaired in overt diabetes and in patients with coronary artery disease. Impaired brachial artery vasoactivity is felt to be an early indicator of atherosclerosis. The authors identified a group of patients with lower extremity peripheral vascular

R Avena; K. M Curry; A. N Sidawy; J. F Simpkins; R. F Neville; M. E Mitchell; M Bukowski

1998-01-01

373

Cerebral Collateral Circulation in Carotid Artery Disease  

PubMed Central

Carotid artery disease is common and increases the risk of stroke. However, there is wide variability on the severity of clinical manifestations of carotid disease, ranging from asymptomatic to fatal stroke. The collateral circulation has been recognized as an important aspect of cerebral circulation affecting the risk of stroke as well as other features of stroke presentation, such as stroke patterns in patients with carotid artery disease. The cerebral circulation attempts to maintain constant cerebral perfusion despite changes in systemic conditions, due to its ability to autoregulate blood flow. In case that one of the major cerebral arteries is compromised by occlusive disease, the cerebral collateral circulation plays an important role in preserving cerebral perfusion through enhanced recruitment of blood flow. With the advent of techniques that allow rapid evaluation of cerebral perfusion, the collateral circulation of the brain and its effectiveness may also be evaluated, allowing for prompt assessment of patients with acute stroke due to involvement of the carotid artery, and risk stratification of patients with carotid stenosis in chronic stages. Understanding the cerebral collateral circulation provides a basis for the future development of new diagnostic tools, risk stratification, predictive models and new therapeutic modalities. In the present review we discuss basic aspects of the cerebral collateral circulation, diagnostic methods to assess collateral circulation, and implications in occlusive carotid artery disease. PMID:21037845

Romero, José R; Pikula, Aleksandra; Nguyen, Thanh N; Nien, Yih Lin; Norbash, Alexander; Babikian, Viken L

2009-01-01

374

Cerebral collateral circulation in carotid artery disease.  

PubMed

Carotid artery disease is common and increases the risk of stroke. However, there is wide variability on the severity of clinical manifestations of carotid disease, ranging from asymptomatic to fatal stroke. The collateral circulation has been recognized as an important aspect of cerebral circulation affecting the risk of stroke as well as other features of stroke presentation, such as stroke patterns in patients with carotid artery disease. The cerebral circulation attempts to maintain constant cerebral perfusion despite changes in systemic conditions, due to its ability to autoregulate blood flow. In case that one of the major cerebral arteries is compromised by occlusive disease, the cerebral collateral circulation plays an important role in preserving cerebral perfusion through enhanced recruitment of blood flow. With the advent of techniques that allow rapid evaluation of cerebral perfusion, the collateral circulation of the brain and its effectiveness may also be evaluated, allowing for prompt assessment of patients with acute stroke due to involvement of the carotid artery, and risk stratification of patients with carotid stenosis in chronic stages. Understanding the cerebral collateral circulation provides a basis for the future development of new diagnostic tools, risk stratification, predictive models and new therapeutic modalities. In the present review we discuss basic aspects of the cerebral collateral circulation, diagnostic methods to assess collateral circulation, and implications in occlusive carotid artery disease. PMID:21037845

Romero, José R; Pikula, Aleksandra; Nguyen, Thanh N; Nien, Yih Lin; Norbash, Alexander; Babikian, Viken L

2009-11-01

375

Stylocarotid artery syndrome.  

PubMed

Stylocarotid artery syndrome is a rare condition that results from compression of the internal or external carotid artery by the styloid process of the temporal bone. Here we present the case of a patient suffering from syncope, monoparesis of the right arm, and dysarthria due to recurrent transient ischemic attacks that resulted from severe compression of the midsegment of the left extracranial internal carotid artery between an elongated styloid process and a C2 vertebral body osteophyte. This case demonstrates successful surgical management of a condition rarely encountered by the vascular surgeon. PMID:25088736

David, Joshua; Lieb, Michael; Rahimi, Saum A

2014-12-01

376

Upregulation of 5-Hydroxytryptamine Receptor Signaling in Coronary Arteries after Organ Culture  

PubMed Central

Background 5-Hydroxytryptamine (5-HT) is a powerful constrictor of coronary arteries and is considered to be involved in the pathophysiological mechanisms of coronary-artery spasm. However, the mechanism of enhancement of coronary-artery constriction to 5-HT during the development of coronary artery disease remains to be elucidated. Organ culture of intact blood-vessel segments has been suggested as a model for the phenotypic changes of smooth muscle cells in cardiovascular disease. Methodology/Principal Findings We wished to characterize 5-HT receptor-induced vasoconstriction and quantify expression of 5-HT receptor signaling in cultured rat coronary arteries. Cumulative application of 5-HT produced a concentration-dependent vasoconstriction in fresh and 24 h-cultured rat coronary arteries without endothelia. 5-HT induced greater constriction in cultured coronary arteries than in fresh coronary arteries. U46619- and CaCl2-induced constriction in the two groups was comparable. 5-HT stimulates the 5-HT2A receptor and cascade of phospholipase C to induce coronary vasoconstriction. Calcium influx through L-type calcium channels and non-L-type calcium channels contributed to the coronary-artery constrictions induced by 5-HT. The contractions mediated by non-L-type calcium channels were significantly enhanced in cultured coronary arteries compared with fresh coronary arteries. The vasoconstriction induced by thapsigargin was also augmented in cultured coronary arteries. The decrease in Orai1 expression significantly inhibited 5-HT-evoked entry of Ca2+ in coronary artery cells. Expression of the 5-HT2A receptor, Orai1 and STIM1 were augmented in cultured coronary arteries compared with fresh coronary arteries. Conclusions An increased contraction in response to 5-HT was mediated by the upregulation of 5-HT2A receptors and downstream signaling in cultured coronary arteries. PMID:25202989

Rao, Fang; Xue, Yu-Mei; Zhou, Zhi-Ling; Liu, Xiao-Ying; Shan, Zhi-Xin; Li, Xiao-Hong; Lin, Qiu-Xiong; Wu, Shu-Lin; Yu, Xi-Yong

2014-01-01

377

Repeated Intra-Arterial Thrombectomy within 72 Hours in a Patient with a Clear Contraindication for Intravenous Thrombolysis  

PubMed Central

Introduction. Treating patients with acute ischemic stroke, proximal arterial vessel occlusion, and absolute contraindication for administering intravenous recombinant tissue plasminogen activator (rtPA) poses a therapeutic challenge. Intra-arterial thrombectomy constitutes an alternative treatment option. Materials and Methods. We report a case of a 57-year-old patient with concomitant gastric adenocarcinoma, who received three intra-arterial thrombectomies in 72 hours due to repeated occlusion of the left medial cerebral artery (MCA). Findings. Intra-arterial recanalization of the left medial cerebral artery was performed three times with initially good success. However, two days later, the right medial cerebral artery became occluded. Owing to the overall poor prognosis at that time and knowing the wishes of the patient, we decided not to perform another intra-arterial recanalization procedure. Conclusion. To our knowledge, this is the first case illustrating the use of repeated intra-arterial recanalization in early reocclusion of intracranial vessels.

Laible, Mona; Möhlenbruch, Markus; Hacke, Werner; Bendszus, Martin; Ringleb, Peter Arthur; Rizos, Timolaos

2015-01-01

378

Genetic Determinants of Arterial Stiffness.  

PubMed

Stiffness of large arteries (called arteriosclerosis) is an independent predictor of cardiovascular morbidity and mortality. Although previous studies have shown that arterial stiffness is moderately heritable, genetic factors contributing to arterial stiffness are largely unknown. In this paper, we reviewed the available literature on genetic variants that are potentially related to arterial stiffness. Most variants have shown mixed depictions of their association with arterial stiffness across multiple studies. Various methods to measure arterial stiffness at different arterial sites can contribute to these inconsistent results. In addition, studies in patient populations with hypertension or atherosclerosis may overestimate the impact of genetic variants on arterial stiffness. Future studies are recommended to standardize current measures of arterial stiffness in different age groups. Studies conducted in normal healthy subjects may also provide better opportunities to find novel genetic variants of arterial stiffness. PMID:25472935

Logan, Jeongok G; Engler, Mary B; Kim, Hyungsuk

2014-12-01

379

Retinal artery occlusion  

MedlinePLUS

... Electrocardiogram Heart monitor for abnormal heart rhythm Duplex Doppler ultrasound of the carotid arteries ... Massage of the eye The clot-busting drug, tissue plasminogen activator (tPA) The health care provider should ...

380

Peripheral artery disease - legs  

MedlinePLUS

... legs; Arterial insufficiency of the legs; Recurrent leg pain and cramping; Calf pain with exercise ... The main symptoms of PAD are pain, achiness, fatigue, burning, or ... These symptoms usually appear during walking or exercise, ...

381

Occlusive Peripheral Arterial Disease  

MedlinePLUS

... Rhythms Heart Valve Disorders Infective Endocarditis Pericardial Disease Sports and the Heart Heart Tumors Atherosclerosis Coronary Artery ... sedative, but no general anesthetic, is given. The success of angioplasty varies, depending on the location of ...

382

Coronary Artery Bypass Surgery  

MedlinePLUS

... t help, you may need coronary artery bypass surgery. The surgery creates a new path for blood to flow ... more than one bypass. The results of the surgery usually are excellent. Many people remain symptom-free ...

383

Peripheral ophthalmic artery aneurysm  

Microsoft Academic Search

Generally speaking, the term “ophthalmic aneurysms” refers to carotid-ophthalmic aneurysms, which arise from the internal\\u000a carotid artery (ICA) wall at or around the origin of the ophthalmic artery (OA). In contrast, aneurysms arising from the OA\\u000a stem or its branches, separate from the ICA are called peripheral OA aneurysms (POAAs). POAAs are a rare entity, which clinical\\u000a features and natural

Liang Qiao; Handong Wang; Lei Mao; Suihua Chen; Wei Xie; Qi Wu

2011-01-01

384

123I MIBG appearance of severe renal artery stenosis.  

PubMed

We describe a patient with labile hypertension and elevated metanephrines who underwent 123Iodine metaiodobenzylguanidine (MIBG) for the detection of a possible paraganglioma. The scan revealed markedly abnormal diffusely increased activity in the right renal parenchyma. A CT angiogram showed severe renal artery stenosis of an atrophic-appearing right kidney and delayed enhancement of the right kidney, consistent with renal dysfunction due to renal artery stenosis. PMID:25243940

Jordan, Alistair; Seltzer, Marc; Siegel, Alan

2014-11-01