Left Ventricular Stroke Volume Quantification by Contrast Echocardiography – Comparison of Linear and Flow-Based Methods to Cardiac Magnetic Resonance

Science.gov (United States)

Dele-Michael, Abiola O.; Fujikura, Kana; Devereux, Richard B; Islam, Fahmida; Hriljac, Ingrid; Wilson, Sean R.; Lin, Fay; Weinsaft, Jonathan W.

2014-01-01

Background Echocardiography (echo) quantified LV stroke volume (SV) is widely used to assess systolic performance after acute myocardial infarction (AMI). This study compared two common echo approaches – predicated on flow (Doppler) and linear chamber dimensions (Teichholz) – to volumetric SV and global infarct parameters quantified by cardiac magnetic resonance (CMR). Methods Multimodality imaging was performed as part of a post-AMI registry. For echo, SV was measured by Doppler and Teichholz methods. Cine-CMR was used for volumetric SV and LVEF quantification, and delayed-enhancement CMR for infarct size. Results 142 patients underwent same-day echo and CMR. On echo, mean SV by Teichholz (78±17ml) was slightly higher than Doppler (75±16ml; Δ=3±13ml, p=0.02). Compared to SV on CMR (78±18ml), mean difference by Teichholz (Δ=−0.2±14; p=0.89) was slightly smaller than Doppler (Δ−3±14; p=0.02) but limits of agreement were similar between CMR and echo methods (Teichholz: −28, 27 ml, Doppler: −31, 24ml). For Teichholz, differences with CMR SV were greatest among patients with anteroseptal or lateral wall hypokinesis (p<0.05). For Doppler, differences were associated with aortic valve abnormalities or root dilation (p=0.01). SV by both echo methods decreased stepwise in relation to global LV injury as assessed by CMR-quantified LVEF and infarct size (p<0.01). Conclusions Teichholz and Doppler calculated SV yield similar magnitude of agreement with CMR. Teichholz differences with CMR increase with septal or lateral wall contractile dysfunction, whereas Doppler yields increased offsets in patients with aortic remodeling. PMID:23488864

Fetal cardiac stroke volume determination by four-dimensional ultrasound with spatio-temporal image correlation compared with two-dimensional and Doppler ultrasonography.

Science.gov (United States)

Rizzo, Giuseppe; Capponi, Alessandra; Cavicchioni, Ottavia; Vendola, Marianne; Arduini, Domenico

2007-12-01

To assess the agreement of stroke volume (SV) measured with two-dimensional (2D) ultrasonography with Doppler capability (vs) four-dimensional (4D) with spatiotemporal image correlation (STIC) in normal and growth restricted fetuses. 2D Doppler and 4D STIC were used to measure SV of 40 normal fetuses at 20 to 22 and 28 to 32 weeks, and 16 growth-restricted fetuses at 26 to 34 weeks of gestation. Intraclass correlation was used to evaluate the agreement between left and right SV obtained by the two techniques, and proportionate Bland-Altman plots constructed. The time necessary to obtain SV was analyzed. The intraclass correlation coefficient between 2D Doppler and 4D STIC measurements for the left ventricle were 0.977 and 0.980 for the right ventricle. The proportionate limits of agreement between the two methods were 18.7 to 23.9% for the left ventricle and - 20.9 to 21.7% for the right ventricle. The time necessary to measure SV was significantly shorter with 4D STIC (3.1 (vs) 7.9 min p < 0.0001) than with 2D Doppler. There is a good agreement between SV measured either by 2D Doppler or by 4D STIC. The 4D STIC represents a simple and rapid technique to estimate fetal SV and promises to become the method of choice. Copyright (c) 2007 John Wiley & Sons, Ltd.

Reduced left ventricular filling following blood volume extraction does not result in compensatory augmentation of cardiac mechanics.

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Lord, Rachel; MacLeod, David; George, Keith; Oxborough, David; Shave, Rob; Stembridge, Mike

2018-04-01

What is the central question of this study? A reduction in left ventricular (LV) filling, and concomitant increase in heart rate, augments LV mechanics to maintain stroke volume (SV); however, the impact of reduced LV filling in isolation on SV and LV mechanics is currently unknown. What is the main finding and its importance? An isolated decrease in LV filling did not provoke a compensatory increase in mechanics to maintain SV; in contrast, LV mechanics and SV were reduced. These data indicate that when LV filling is reduced without changes in heart rate, LV mechanics do not compensate to maintain SV. An acute non-invasive reduction in preload has been shown to augment cardiac mechanics to maintain stroke volume and cardiac output. Such interventions induce concomitant changes in heart rate, whereas blood volume extraction reduces preload without changes in heart rate. Therefore, the purpose of this study was to determine whether a preload reduction in isolation resulted in augmented stroke volume achieved via enhanced cardiac mechanics. Nine healthy volunteers (four female, age 29 ± 11 years) underwent echocardiography for the assessment of left ventricular (LV) volumes and mechanics in a supine position at baseline and end extraction after the controlled removal of 25% of total blood volume (1062 ± 342 ml). Arterial blood pressure was monitored continuously by a pressure transducer attached to an indwelling radial artery catheter. Heart rate and total peripheral resistance were unchanged from baseline to end extraction, but systolic blood pressure was reduced (from 148 to 127 mmHg). From baseline to end extraction there were significant reductions in left ventricular end-diastolic volume (from 89 to 71 ml) and stroke volume (from 56 to 37 ml); however, there was no change in LV twist, basal or apical rotation. In contrast, LV longitudinal strain (from -20 to -17%) and basal circumferential strain (from -22 to -19%) were significantly reduced from

Clinically significant change in stroke volume in pulmonary hypertension

NARCIS (Netherlands)

van Wolferen, S.A.; van de Veerdonk, M.C.; Mauritz, G.J.; Jacobs, W.; Marcus, J.T.; Marques, K.M.J.; Bronzwaer, J.G.F.; Heijmans, M.W.; Boonstra, A.; Postmus, P.E.; Westerhof, N.; Noordegraaf, A.V.

2011-01-01

Background: Stroke volume is probably the best hemodynamic parameter because it reflects therapeutic changes and contains prognostic information in pulmonary hypertension (PH). Stroke volume directly reflects right ventricular function in response to its load, without the correction of compensatory

Accuracy and reliability of noninvasive stroke volume monitoring via ECG-gated 3D electrical impedance tomography in healthy volunteers

Science.gov (United States)

Proença, Martin; Adler, Andy; Riedel, Thomas; Thiran, Jean-Philippe; Solà, Josep

2018-01-01

Cardiac output (CO) and stroke volume (SV) are parameters of key clinical interest. Many techniques exist to measure CO and SV, but are either invasive or insufficiently accurate in clinical settings. Electrical impedance tomography (EIT) has been suggested as a noninvasive measure of SV, but inconsistent results have been reported. Our goal is to determine the accuracy and reliability of EIT-based SV measurements, and whether advanced image reconstruction approaches can help to improve the estimates. Data were collected on ten healthy volunteers undergoing postural changes and exercise. To overcome the sensitivity to heart displacement and thorax morphology reported in previous work, we used a 3D EIT configuration with 2 planes of 16 electrodes and subject-specific reconstruction models. Various EIT-derived SV estimates were compared to reference measurements derived from the oxygen uptake. Results revealed a dramatic impact of posture on the EIT images. Therefore, the analysis was restricted to measurements in supine position under controlled conditions (low noise and stable heart and lung regions). In these measurements, amplitudes of impedance changes in the heart and lung regions could successfully be derived from EIT using ECG gating. However, despite a subject-specific calibration the heart-related estimates showed an error of 0.0 ± 15.2 mL for absolute SV estimation. For trending of relative SV changes, a concordance rate of 80.9% and an angular error of −1.0 ± 23.0° were obtained. These performances are insufficient for most clinical uses. Similar conclusions were derived from lung-related estimates. Our findings indicate that the key difficulty in EIT-based SV monitoring is that purely amplitude-based features are strongly influenced by other factors (such as posture, electrode contact impedance and lung or heart conductivity). All the data of the present study are made publicly available for further investigations. PMID:29373611

Radiocardiographic determination of the stroke volume and of the heart minute volume in athletes

Energy Technology Data Exchange (ETDEWEB)

Sattler, R; Stoll, W [Friedrich-Schiller-Universitaet, Jena (German Democratic Republic). Radiologische Klinik

1981-11-01

Radiocardiography, a novel radioisotope method for the problemless determination of many cardiodynamic parameters which can be applied also at given physical exercise is presented. On the basis of stroke volume and heart minute volume values from 35 athletes practising different sports and of a comparison with normal values reported in the literature, differences in the cardiac adaptation and the function of athletic hearts and so-called normal hearts are pointed out. The stroke volume of endurance-trained athletes exceeds that of untrained individuals by 30-40 ml. Under exercise the increase of the stroke volume is considerably greater in endurance athletes than in individuals practising other sports or in untrained subjects. At rest the values of the heart minute volume are almost the same in athletes and untrained individuals. Under exercise the heart minute volume of endurance athletes (40 l/min) is nearly twice that of untrained individuals (volume reserve of the athlete).

Radiocardiographic determination of the stroke volume and of the heart minute volume in athletes

International Nuclear Information System (INIS)

Sattler, R.; Stoll, W.

1981-01-01

Radiocardiography, a novel radioisotope method for the problemless determination of many cardiodynamic parameters which can be applied also at given physical exercise is presented. On the basis of stroke volume and heart minute volume values from 35 athletes practising different sports and of a comparison with normal values reported in the literature, differences in the cardiac adaptation and the function of athletic hearts and so-called normal hearts are pointed out. The stroke volume of endurance-trained athetes exceed that of untrained individuals by 30-40 ml. Under exercise the increase of the stroke volume is considerably greater in endurance athletes than in individuals practising other sports or in untrained subjects. At rest the values of the heart minute volume are almost the same in athletes and untrained individuals. Under exercise the heart minute volume of endurance athletes (40 l/min) is nearly twice that of untrained individuals (volume reserve of the athlete). (author)

Two-dimensional color Doppler echocardiography for left ventricular stroke volume assessment: a comparison study with three-dimensional echocardiography.

Science.gov (United States)

Silva, Cristina Da; Pedro, Fátima; Deister, Lizandra; Sahlén, Anders; Manouras, Aristomenis; Shahgaldi, Kambiz

2012-08-01

Whether measurement of left ventricular outflow tract diameter (LVOTd) using color Doppler (CD) in order to more accurately define LVOTd is more accurate for determination of stroke volume (SV) than gray scale and compare it with direct measurement of LVOT area (a) using three-dimensional echocardiography (3DE) for SV determination. Twenty-one volunteers were examined. LVOTa was calculated by two-dimensional echocardiography (2DE) using the following formula: π× (d/2)(2) , d = LVOT diameter by gray scale and CD, respectively. Planimetry of LVOTa was performed in parasternal long axis using 3DE. Eccentricity Index was calculated using the lateral and anterior-posterior LVOTd. SV was obtained by four different methods: (1) 2D gray scale, (2) 2D color, (3) LVOTa × LVOT velocity time integral, and (4) SV by Simpson's biplane method. Gray scale LVOTd was significantly smaller compared to LVOTd obtained with CD (P vs 3.67 ± 0.70 cm(2) , P vs 3.61 ± 0.89 cm(2) , P = 0.011). Half of the subjects had at least 17% difference between the lateral and anterior-posterior LVOTd. There were significant differences between SV by 2D gray scale and 2D CD (82.8 ± 17.1 mL vs 92.4 ± 16.8 mL, P vs 90.7 ± 19.8 mL, P = 0.025). Our study demonstrates LVOT being frequently elliptical. SV and LVOTa were found to be similar when comparing 2DE CD and 3DE planimetry and showed higher values in comparison to 2DE gray scale, which suggests 2DE CD to be an alternative approach for SV assessment. © 2012, Wiley Periodicals, Inc.

Ischemic Volume and Neurological Deficit: Correlation of Computed Tomography Perfusion with the National Institutes of Health Stroke Scale Score in Acute Ischemic Stroke.

Science.gov (United States)

Furlanis, Giovanni; Ajčević, Miloš; Stragapede, Lara; Lugnan, Carlo; Ridolfi, Mariana; Caruso, Paola; Naccarato, Marcello; Ukmar, Maja; Manganotti, Paolo

2018-04-30

The National Institutes of Health Stroke Scale (NIHSS) is the most adopted stroke patients' evaluation tool in emergency settings to assess the severity of stroke and to determine the patients' eligibility for specific treatments. Computed tomography perfusion (CTP) is crucial to identify salvageable tissue that can benefit from the reperfusion treatment. The aim of this study is to identify the relation between the NIHSS scores and the hypoperfused volumes evaluated by CTP in patients with hyperacute ischemic stroke. This retrospective study was conducted on 105 patients with ischemic stroke who underwent NIHSS assessment and CTP in the hyperacute phase. Hypoperfused volume was evaluated by CTP maps processed with semi-automatic algorithm. An analysis was conducted to determine the degree of correlation between the NIHSS scores and the ischemic lesion volumes and to investigate the relation between the anterior and the posterior circulation strokes, as well as between the right and the left hemispheric strokes. A significant correlation was found between ischemic volume and NIHSS score at baseline (r = .82; P correlation was identified in the anterior circulation stroke (r = .76; P correlated for the left and the right hemispheric strokes (r = .83 and .81; P correlation between the baseline NIHSS score and the ischemic volume estimated by CTP. We confirmed that NIHSS is a reliable predictor of perfusion deficits in acute ischemic stroke. CTP allows fast imaging assessment in the hyperacute phase. The results highlight the importance of these diagnostic tools in the assessment of stroke severity and in acute decision-making. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Case volumes of intra-arterial and intravenous treatment of ischemic stroke in the USA.

Science.gov (United States)

Hirsch, J A; Yoo, A J; Nogueira, R G; Verduzco, L A; Schwamm, L H; Pryor, J C; Rabinov, J D; González, R G

2009-07-01

Ischemic stroke is a major cause of disability and death in the USA. Intravenous tissue plasminogen activator (t-PA) remains underutilized. With the development of newer intra-arterial reperfusion therapies, there is increased opportunity to address the more devastating large-vessel occlusions. We seek to identify the numbers of patients with stroke treated with intravenous and intra-arterial therapies, as well as to estimate the potential number of intra-arterial cases in the foreseeable future. We performed a literature search to determine case volumes of intravenous t-PA use. We extrapolated the current case volume of intra-arterial stroke therapies from the numbers of cases in which the Merci retrieval device was used. In order to estimate the potential numbers of intra-arterial stroke cases, we characterized the percentage of patients with stroke who received intra-arterial therapy at two leading stroke centers. We applied these percentages to the numbers of patients with stroke seen at the top 100, 200 and 500 stroke centers by volume. The rate of intravenous t-PA use is 2.4-3.6%, resulting in 15 000-22 000 cases/year in the USA. The estimated case volume of intra-arterial therapies is 3500-7200 in 2006. Based on data from St. Luke's Brain and Stroke Institute and Massachusetts General Hospital, approximately 5-20% of patients with ischemic stroke can be treated with intra-arterial therapies. Extrapolating this to the top 500 stroke centers by volume, the potential number of intra-arterial cases in the USA is 10 400-41 500/year. Based on the current numbers of intra-arterial cases, our theoretical model identifies a potential for significant growth of this stroke therapy.

The value of serum mean platelet volume in ischaemic stroke patient

International Nuclear Information System (INIS)

Tamer, F.; Fevzi, Y.; Deniz, A.E.; Cemil, K.; Cihat, Y.; Muhittin, Y.; Serkan, Y.M.; Ali, C.M.; Faith, B.

2013-01-01

Objective: To investigate the value of serum Mean Platelet Volume in acute ischaemic stroke patients. Method: The retrospective case-control study was conducted at Ankara Numune Training and Research Hospital in Turkey and comprised record of patients of acute ischaemic stroke admitted to the Emergency Department between June 2010 and January 2012. The two groups were statistically compared using SPSS 18.0. Result: Overall, there were 482 stroke patients (Group 1) and 315 subjects as controls (Group 2). The median value in Group 1 was 9.0 (2.1) (fL), while in Group 2 it was 8.80 (2.4) (fL). The difference was statistically significant (Z=-2.80; p<0.05). Conclusion: Mean Platelet Volume increased in the stroke patients. (author)

Impedance cardiography: Pulsatile blood flow and the biophysical and electrodynamic basis for the stroke volume equations

Directory of Open Access Journals (Sweden)

Donald P Bernstein

2010-01-01

Full Text Available Impedance cardiography (ICG is a branch of bioimpedance pimarily concerned with the determination of left ventricular stroke volume (SV. As implemented, using the transthoracic approach, the technique involves applying a current field longitudinally across a segment of thorax by means of a constant magnitude, high frequency, low amplitude alternating current (AC. By Ohm's Law, the voltage difference measured within the current field is proportional to the electrical impedance Z (Ω. Without ventilatory or cardiac activity, Z is known as the transthoracic, static base impedance Z0. Upon ventricular ejection, a characteristic time dependent cardiac-synchronous pulsatile impedance change is obtained, ΔZ(t, which, when placed electrically in parallel with Z0, constitutes the time-variable total transthoracic impedance Z(t. ΔZ(t represents a dual-element composite waveform, which comprises both the radially-oriented volumetric expansion of and axially-directed forward blood flow within both great thoracic arteries. In its majority, however, ΔZ(t is known to primarily emanate from the ascending aorta. Conceptually, commonly implemented methods assume a volumetric origin for the peak systolic upslope of ΔZ(t, (i.e. dZ/dtmax, with the presumed units of Ω·s-1. A recently introduced method assumes the rapid ejection of forward flowing blood in earliest systole causes significant changes in the velocity-induced blood resistivity variation (Δρb(t, Ωcm·s-1, and it is the peak rate of change of the blood resistivity variation dρb(t/dtmax (Ωcm·s-2 that is the origin of dZ/dtmax. As a consequence of dZ/dtmax peaking in the time domain of peak aortic blood acceleration, dv/dtmax (cm·s-2, it is suggested that dZ/dtmax is an ohmic mean acceleration analog (Ω·s-2 and not a mean flow or velocity surrogate as generally assumed. As conceptualized, the normalized value, dZ/dtmax/Z0, is a dimensionless ohmic mean acceleration equivalent (s-2

ACE Gene in Egyptian Ischemic Stroke Patients.

Science.gov (United States)

Mostafa, Magdy A; El-Nabiel, Lobna M; Fahmy, Nagia Aly; Aref, Hany; Shreef, Edrees; Abd El-Tawab, Fathy; Abdulghany, Osama M

2016-09-01

Angiotensin-1-converting enzyme (ACE) is a crucial player in vascular homeostasis and in the pathogenesis of atherosclerosis and hypertension. The present study was conducted to determine whether there is an association between the ACE insertion/deletion (I/D) polymorphism and ischemic stroke in Egyptian population. Also, we analyzed the ACE gene I/D polymorphism as a risk factor for small-vessel (SV) versus large-vessel (LV) disease. Sixty patients with ischemic stroke were included: 30 with SV disease and 30 with LV disease. In addition, a control group of 30 apparent healthy subjects were studied. Clinical assessment, computed tomography, magnetic resonance imaging brain, and genetic study using the polymerase chain reaction of ACE gene were done for all subjects. We found that the distribution of ACE gene polymorphism frequency was significantly different between the 3 groups. The DD genotype was far more common in stroke patients compared to controls. It was also significantly more common in each of the patient groups compared to controls but rather similar in the 2 patient groups with SV and LV diseases. We found that the ACE gene deletion/deletion genotype is common in Egyptian patients with non-cardioembolic ischemic stroke but does not appear to be specific neither to SV nor to LV disease. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Radionuclide stroke count ratios for assessment of right and left ventricular volume overload in children

International Nuclear Information System (INIS)

Parrish, M.D.; Graham, T.P. Jr.; Born, M.L.; Jones, J.P.; Boucek, R.J. Jr.; Artman, M.; Partain, C.L.

1983-01-01

The ratio of left ventricular to right ventricular stroke counts measured by radionuclide angiography has been used in adults to estimate the severity of left-sided valvular regurgitation. The validation of this technique in children for assessment of right and left ventricular volume overload is reported herein. Radionuclide stroke count ratios in 60 children aged 0.5 to 19 years (mean 11) were determined. Based on their diagnoses, the patients were divided into 3 groups: (1) normal--40 patients with no shunts or valvular regurgitation, (2) left ventricular volume overload--13 patients with mitral or aortic regurgitation, or both, and (3) right ventricular volume overload--7 patients, 2 with severe tricuspid regurgitation, 3 with atrial septal defects, and 2 with total anomalous pulmonary venous drainage. The radionuclide stroke count ratio clearly differentiated these groups (p less than 0.05): normal patients had a stroke count ratio of 1.04 +/- 0.17 (mean +/- 1 standard deviation), the left ventricular volume overload group had a stroke count ratio of 2.43 +/- 0.86, and the right ventricular volume overload group had a stroke count ratio of 0.44 +/- 0.17. In 22 of our 60 patients, radionuclide stroke count ratios were compared with cineangiographic stroke volume ratios, resulting in a correlation coefficient of 0.88. It is concluded that radionuclide ventriculography is an excellent tool for qualitative and quantitative assessment of valvular regurgitation in children

Very Low Cerebral Blood Volume Predicts Parenchymal Hematoma in Acute Ischemic Stroke

DEFF Research Database (Denmark)

Hermitte, Laure; Cho, Tae-Hee; Ozenne, Brice

2013-01-01

BACKGROUND AND PURPOSE: Parenchymal hematoma (PH) may worsen the outcome of patients with stroke. The aim of our study was to confirm the relationship between the volume of very low cerebral blood volume (CBV) and PH using a European multicenter database (I-KNOW). A secondary objective was to exp......BACKGROUND AND PURPOSE: Parenchymal hematoma (PH) may worsen the outcome of patients with stroke. The aim of our study was to confirm the relationship between the volume of very low cerebral blood volume (CBV) and PH using a European multicenter database (I-KNOW). A secondary objective...

The association of insular stroke with lesion volume

Directory of Open Access Journals (Sweden)

Nishanth Kodumuri

2016-01-01

Full Text Available The insula has been implicated in many sequelae of stroke. It is the area most commonly infarcted in people with post-stroke arrhythmias, loss of thermal sensation, hospital acquired pneumonia, and apraxia of speech. We hypothesized that some of these results reflect the fact that: (1 ischemic strokes that involve the insula are larger than strokes that exclude the insula (and therefore are associated with more common and persistent deficits; and (2 insular involvement is a marker of middle cerebral artery (MCA occlusion. We analyzed MRI scans of 861 patients with acute ischemic hemispheric strokes unselected for functional deficits, and compared infarcts involving the insula to infarcts not involving the insula using t-tests for continuous variables and chi square tests for dichotomous variables. Mean infarct volume was larger for infarcts including the insula (n = 232 versus excluding the insula (n = 629: 65.8 ± 78.8 versus 10.2 ± 15.9 cm3 (p < 0.00001. Even when we removed lacunar infarcts, mean volume of non-lacunar infarcts that included insula (n = 775 were larger than non-lacunar infarcts (n = 227 that excluded insula: 67.0 cm3 ± 79.2 versus 11.5 cm3 ± 16.7 (p < 0.00001. Of infarcts in the 90th percentile for volume, 87% included the insula (χ2 = 181.8; p < 0.00001. Furthermore, 79.0% infarcts due to MCA occlusion included the insula; 78.5% of infarcts without MCA occlusion excluded the insula (χ2 = 93.1; p < 0.0001. The association between insular damage and acute or chronic sequelae likely often reflects the fact that insular infarct is a marker of large infarcts caused by occlusion of the MCA more than a specific role of the insula in a range of functions. Particularly in acute stroke, some deficits may also be due to ischemia of the MCA or ICA territory caused by large vessel occlusion.

Limitations and pitfalls in measurements of right ventricular stroke volume in an animal model of right heart failure

International Nuclear Information System (INIS)

Vildbrad, Mads Dam; Andersen, Asger; Andersen, Thomas Krarup; Axelgaard, Sofie; Holmboe, Sarah; Andersen, Stine; Nielsen-Kudsk, Jens Erik; Ringgaard, Steffen

2015-01-01

Right heart failure occurs in various heart and pulmonary vascular diseases and may be fatal. We aimed to identify limitations in non-invasive measurements of right ventricular stroke volume in an animal model of right ventricular failure. Data from previous studies randomising rats to pulmonary trunk banding (PTB, n = 33) causing pressure-overload right ventricular failure or sham operation (n = 16) was evaluated retrospectively. We measured right ventricular stroke volume by high frequency echocardiography and magnetic resonance imaging (MRI). We found correlation between right ventricular stroke volume measured by echocardiography and MRI in the sham animals (r = 0.677, p = 0.004) but not in the PTB group. Echocardiography overestimated the stroke volume compared to MRI in both groups. Intra- and inter-observer variation did not explain the difference. Technical, physiological and anatomical issues in the pulmonary artery might explain why echocardiography over-estimates stroke volume. Flow acceleration close to the pulmonary artery banding can cause uncertainties in the PTB model and might explain the lack of correlation. In conclusion, we found a correlation in right ventricular stroke volume measured by echocardiography versus MRI in the sham group but not the PTB group. Echocardiography overestimated right ventricular stroke volume compared to MRI. (paper)

Changes in superior mesenteric artery Doppler waveform during reduction of cardiac stroke volume and hypotension

DEFF Research Database (Denmark)

Perko, M J; Perko, Grazyna; Just, S

1996-01-01

the hypovolemia. Alterations in pV and pulsatility indices were closely related to changes in stroke volume, and a negative correlation was found between diastolic velocities and stroke volume. regression analysis showed no significant relation between variations in velocity parameters and blood pressure. Results...

The effect of endogenously released glucose, insulin, glucagon-like peptide 1, ghrelin on cardiac output, heart rate, stroke volume, and blood pressure.

Science.gov (United States)

Hlebowicz, Joanna; Lindstedt, Sandra; Björgell, Ola; Dencker, Magnus

2011-12-29

Ingestion of a meal increases the blood flow to the gastrointestinal organs and affects the heart rate (HR), blood pressure and cardiac output (CO), although the mechanisms are not known. The aim of this study was to evaluate the effect of endogenously released glucose, insulin, glucagon-like peptide 1 (GLP-1), ghrelin on CO, HR, stroke volume (SV), and blood pressure. Eleven healthy men and twelve healthy women ((mean ± SEM) aged: 26 ± 0.2 y; body mass index: 21.8 ± 0.1 kg/m(2))) were included in this study. The CO, HR, SV, systolic and diastolic blood pressure, antral area, gastric emptying rate, and glucose, insulin, GLP-1 and ghrelin levels were measured. The CO and SV at 30 min were significantly higher, and the diastolic blood pressure was significantly lower, than the fasting in both men and women (P blood pressure (P = 0.021, r = -0.681), and the change in SV (P = 0.008, r = -0.748) relative to the fasting in men. The insulin 0-30 min AUC was significantly correlated to the CO 0-30 min AUC (P = 0.002, r = 0.814) in men. Significant correlations were also found between the 0-120 min ghrelin and HR AUCs (P = 0.007, r = 0.966) in men. No statistically significant correlations were seen in women. Physiological changes in the levels of glucose, insulin, GLP-1 and ghrelin may influence the activity of the heart and the blood pressure. There may also be gender-related differences in the haemodynamic responses to postprandial changes in hormone levels. The results of this study show that subjects should not eat immediately prior to, or during, the evaluation of cardiovascular interventions as postprandial affects may affect the results, leading to erroneous interpretation of the cardiovascular effects of the primary intervention. NCT01027507.

Seasonal variation and trends in stroke hospitalizations and mortality in a South American community hospital.

Science.gov (United States)

Díaz, Alejandro; Gerschcovich, Eliana Roldan; Díaz, Adriana A; Antía, Fabiana; Gonorazky, Sergio

2013-10-01

Numerous studies have reported the presence of temporal variations in biological processes. Seasonal variation (SV) in stroke has been widely studied, but little data have been published on this phenomenon in the Southern Hemisphere, and there have been no studies reported from Argentina. The goals of the present study were to describe the SV of admissions and deaths for stroke and examine trends in stroke morbidity and mortality over a 3-year period in a community hospital in Argentina. Hospital discharge reports from the electronic database of vital statistics between 1999 and 2001 were examined retrospectively. Patients who had a main discharge diagnosis of stroke (ischemic or hemorrhagic) or cerebrovascular accident (International Classification of Diseases, Ninth Revision codes 431, 432, 434, and 436) were selected. The study sample included 1382 hospitalizations by stroke (3.5% of all admissions). In-hospital mortality demonstrated a winter peak (25.5% vs 17% in summer; P = .001). The crude seasonal stroke attack rate (ischemic and hemorrhagic) was highest in winter (164 per 100,000 population; 95% CI, 159-169 per 100,000) and lowest in summer (124 per 100,000; 95% CI, 120-127 per 100,000; P = .008). Stroke admissions followed a seasonal pattern, with a winter-spring predominance (P = .008). Our data indicate a clear SV in stroke deaths and admissions in this region of Argentina. The existence of SV in stroke raises a different hypothesis about the rationale of HF admissions and provides information for the organization of care and resource allocation. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Infarct volume predicts critical care needs in stroke patients treated with intravenous thrombolysis

Energy Technology Data Exchange (ETDEWEB)

Faigle, Roland; Marsh, Elisabeth B.; Llinas, Rafael H.; Urrutia, Victor C. [Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, MD (United States); Wozniak, Amy W. [Johns Hopkins University, Department of Biostatistics, Bloomberg School of Public Health, Baltimore, MD (United States)

2014-10-26

Patients receiving intravenous thrombolysis with recombinant tissue plasminogen activator (IVT) for ischemic stroke are monitored in an intensive care unit (ICU) or a comparable unit capable of ICU interventions due to the high frequency of standardized neurological exams and vital sign checks. The present study evaluates quantitative infarct volume on early post-IVT MRI as a predictor of critical care needs and aims to identify patients who may not require resource intense monitoring. We identified 46 patients who underwent MRI within 6 h of IVT. Infarct volume was measured using semiautomated software. Logistic regression and receiver operating characteristics (ROC) analysis were used to determine factors associated with ICU needs. Infarct volume was an independent predictor of ICU need after adjusting for age, sex, race, systolic blood pressure, NIH Stroke Scale (NIHSS), and coronary artery disease (odds ratio 1.031 per cm{sup 3} increase in volume, 95 % confidence interval [CI] 1.004-1.058, p = 0.024). The ROC curve with infarct volume alone achieved an area under the curve (AUC) of 0.766 (95 % CI 0.605-0.927), while the AUC was 0.906 (95 % CI 0.814-0.998) after adjusting for race, systolic blood pressure, and NIHSS. Maximum Youden index calculations identified an optimal infarct volume cut point of 6.8 cm{sup 3} (sensitivity 75.0 %, specificity 76.7 %). Infarct volume greater than 3 cm{sup 3} predicted need for critical care interventions with 81.3 % sensitivity and 66.7 % specificity. Infarct volume may predict needs for ICU monitoring and interventions in stroke patients treated with IVT. (orig.)

Infarct volume predicts critical care needs in stroke patients treated with intravenous thrombolysis

International Nuclear Information System (INIS)

Faigle, Roland; Marsh, Elisabeth B.; Llinas, Rafael H.; Urrutia, Victor C.; Wozniak, Amy W.

2015-01-01

Patients receiving intravenous thrombolysis with recombinant tissue plasminogen activator (IVT) for ischemic stroke are monitored in an intensive care unit (ICU) or a comparable unit capable of ICU interventions due to the high frequency of standardized neurological exams and vital sign checks. The present study evaluates quantitative infarct volume on early post-IVT MRI as a predictor of critical care needs and aims to identify patients who may not require resource intense monitoring. We identified 46 patients who underwent MRI within 6 h of IVT. Infarct volume was measured using semiautomated software. Logistic regression and receiver operating characteristics (ROC) analysis were used to determine factors associated with ICU needs. Infarct volume was an independent predictor of ICU need after adjusting for age, sex, race, systolic blood pressure, NIH Stroke Scale (NIHSS), and coronary artery disease (odds ratio 1.031 per cm 3 increase in volume, 95 % confidence interval [CI] 1.004-1.058, p = 0.024). The ROC curve with infarct volume alone achieved an area under the curve (AUC) of 0.766 (95 % CI 0.605-0.927), while the AUC was 0.906 (95 % CI 0.814-0.998) after adjusting for race, systolic blood pressure, and NIHSS. Maximum Youden index calculations identified an optimal infarct volume cut point of 6.8 cm 3 (sensitivity 75.0 %, specificity 76.7 %). Infarct volume greater than 3 cm 3 predicted need for critical care interventions with 81.3 % sensitivity and 66.7 % specificity. Infarct volume may predict needs for ICU monitoring and interventions in stroke patients treated with IVT. (orig.)

Improved cardiac filling facilitates the postprandial elevation of stroke volume in Python regius.

Science.gov (United States)

Enok, Sanne; Leite, Gabriella S P C; Leite, Cléo A C; Gesser, Hans; Hedrick, Michael S; Wang, Tobias

2016-10-01

To accommodate the pronounced metabolic response to digestion, pythons increase heart rate and elevate stroke volume, where the latter has been ascribed to a massive and fast cardiac hypertrophy. However, numerous recent studies show that heart mass rarely increases, even upon ingestion of large meals, and we therefore explored the possibility that a rise in mean circulatory filling pressure (MCFP) serves to elevate venous pressure and cardiac filling during digestion. To this end, we measured blood flows and pressures in anaesthetized Python regius The anaesthetized snakes exhibited the archetypal tachycardia as well as a rise in both venous pressure and MCFP that fully account for the approximate doubling of stroke volume. There was no rise in blood volume and the elevated MCFP must therefore stem from increased vascular tone, possibly by means of increased sympathetic tone on the veins. Furthermore, although both venous pressure and MCFP increased during volume loading, there was no evidence that postprandial hearts were endowed with an additional capacity to elevate stroke volume. In vitro measurements of force development of paced ventricular strips also failed to reveal signs of increased contractility, but the postprandial hearts had higher activities of cytochrome oxidase and pyruvate kinase, which probably serves to sustain the rise in cardiac work during digestion. © 2016. Published by The Company of Biologists Ltd.

SvABA

DEFF Research Database (Denmark)

Wala, Jeremiah A; Bandopadhayay, Pratiti; Greenwald, Noah

2018-01-01

Structural variants (SVs), including small insertion and deletion variants (indels), are challenging to detect through standard alignment-based variant calling methods. Sequence assembly offers a powerful approach to identifying SVs, but is difficult to apply at scale genome-wide for SV detection...... due to its computational complexity and the difficulty of extracting SVs from assembly contigs. We describe SvABA, an efficient and accurate method for detecting SVs from short-read sequencing data using genome-wide local assembly with low memory and computing requirements. We evaluated Sv...... complex somatic rearrangements with chains of short (applied SvABA to 344 cancer genomes from 11 cancer types and found that short templated-sequence insertions occur in ∼4% of all somatic rearrangements. Finally, we...

Acute effects of volume-oriented incentive spirometry on chest wall volumes in patients after a stroke.

Science.gov (United States)

Lima, Illia Ndf; Fregonezi, Guilherme Af; Melo, Rodrigo; Cabral, Elis Ea; Aliverti, Andrea; Campos, Tânia F; Ferreira, Gardênia Mh

2014-07-01

The aim of the present study was to assess how volume-oriented incentive spirometry applied to patients after a stroke modifies the total and compartmental chest wall volume variations, including both the right and left hemithoraces, compared with controls. Twenty poststroke patients and 20 age-matched healthy subjects were studied by optoelectronic plethysmography during spontaneous quiet breathing (QB), during incentive spirometry, and during the recovery period after incentive spirometry. Incentive spirometry was associated with an increased chest wall volume measured at the pulmonary rib cage, abdominal rib cage and abdominal compartment (P = .001) and under 3 conditions (P spirometry, and postincentive spirometry, respectively. Under all 3 conditions, the contribution of the abdominal compartment to VT was greater in the stroke subjects (54.1, 43.2, and 48.9%) than in the control subjects (43.7, 40.8, and 46.1%, P = .039). In the vast majority of subjects (13/20 and 18/20 during QB and incentive spirometry, respectively), abdominal expansion precedes rib cage expansion during inspiration. Greater asymmetry between the right and left hemithoracic expansions occurred in stroke subjects compared with control subjects, but it decreased during QB (62.5%, P = .002), during incentive spirometry (19.7%), and postincentive spirometry (67.6%, P = .14). Incentive spirometry promotes increased expansion in all compartments of the chest wall and reduces asymmetric expansion between the right and left parts of the pulmonary rib cage; therefore, it should be considered as a tool for rehabilitation. Copyright © 2014 by Daedalus Enterprises.

Evaluation of Accordance of Magnetic Resonance Volumetric and Flow Measurements in Determining Ventricular Stroke Volume in Cardiac Patients

International Nuclear Information System (INIS)

Jeltsch, M.; Ranft, S.; Klass, O.; Aschoff, A.J.; Hoffmann, M.H.K.

2008-01-01

Background: Cardiovascular magnetic resonance imaging (CMR) has become an established noninvasive method for evaluating ventricular function utilizing three-dimensional volumetry. Postprocessing of volumetric measurements is still tedious and time consuming. Stroke volumes obtained by flow quantification across the aortic root or pulmonary trunk could be utilized to increase both speed of workflow and accuracy. Purpose: To assess accuracy of stroke volume quantification using MR volumetric imaging compared to flow quantification in patients with various cardiac diseases. Strategies for the augmentation of accuracy in clinical routine were deduced. Material and Methods: 78 patients with various cardiac diseases -excluding intra- or extracardiac shunts, regurgitant valvular defects, or heart rhythm disturbance -underwent cardiac function analysis with flow measurements across the aortic root and cine imaging of the left ventricle. Forty-six patients additionally underwent flow measurements in the pulmonary trunk and cine imaging of the right ventricle. Results: Left ventricular stroke volume (LVSV) and stroke volume of the aortic root (SVAo) correlated with r=0.97, and Bland-Altman analysis showed a mean difference of 0.11 ml and a standard error of estimation (SEE) of 4.31 ml. Ninety-two percent of the data were within the 95% limits of agreement. Right ventricular stroke volume (RVSV) and stroke volume of the pulmonary trunk (SVP) correlated with a factor of r=0.86, and mean difference in the Bland-Altman analysis was fixed at -2.62 ml (SEE 8.47 ml). For RVSV and SVP, we calculated r=0.82, and Bland-Altman analysis revealed a mean difference of 1.27 ml (SEE 9.89 ml). LVSV and RVSV correlated closely, with r=0.91 and a mean difference of 2.79 ml (SEE 7.17 ml). SVAo and SVP correlated with r=0.95 and a mean difference of 0.50 ml (SEE 5.56 ml). Conclusion: Flow quantification can be used as a guidance tool, providing accurate and reproducible stroke volumes of both

Splenectomy reduces infarct volume and neuroinflammation in male but not female mice in experimental stroke

Science.gov (United States)

Dotson, Abby L.; Wang, Jianming; Saugstad, Julie; Murphy, Stephanie J.; Offner, Halina

2014-01-01

The peripheral immune response contributes to neurodegeneration after stroke yet little is known about how this process differs between males and females. The current study demonstrates that splenectomy prior to experimental stroke eliminates sex differences in infarct volume and activated brain monocytes/microglia. In the periphery of both sexes, activated T cells correlate directly with stroke outcome while monocytes are reduced by splenectomy only in males. This study provides new information about the sex specific mechanisms of the peripheral immune response in neurodegeneration after stroke and demonstrates the need for representation of both sexes in basic and clinical stroke research. PMID:25434281

Echocardiography underestimates stroke volume and aortic valve area: implications for patients with small-area low-gradient aortic stenosis.

Science.gov (United States)

Chin, Calvin W L; Khaw, Hwan J; Luo, Elton; Tan, Shuwei; White, Audrey C; Newby, David E; Dweck, Marc R

2014-09-01

Discordance between small aortic valve area (AVA; area (LVOTarea) and stroke volume alongside inconsistencies in recommended thresholds. One hundred thirty-three patients with mild to severe AS and 33 control individuals underwent comprehensive echocardiography and cardiovascular magnetic resonance imaging (MRI). Stroke volume and LVOTarea were calculated using echocardiography and MRI, and the effects on AVA estimation were assessed. The relationship between AVA and MPG measurements was then modelled with nonlinear regression and consistent thresholds for these parameters calculated. Finally the effect of these modified AVA measurements and novel thresholds on the number of patients with small-area low-gradient AS was investigated. Compared with MRI, echocardiography underestimated LVOTarea (n = 40; -0.7 cm(2); 95% confidence interval [CI], -2.6 to 1.3), stroke volumes (-6.5 mL/m(2); 95% CI, -28.9 to 16.0) and consequently, AVA (-0.23 cm(2); 95% CI, -1.01 to 0.59). Moreover, an AVA of 1.0 cm(2) corresponded to MPG of 24 mm Hg based on echocardiographic measurements and 37 mm Hg after correction with MRI-derived stroke volumes. Based on conventional measures, 56 patients had discordant small-area low-gradient AS. Using MRI-derived stroke volumes and the revised thresholds, a 48% reduction in discordance was observed (n = 29). Echocardiography underestimated LVOTarea, stroke volume, and therefore AVA, compared with MRI. The thresholds based on current guidelines were also inconsistent. In combination, these factors explain > 40% of patients with discordant small-area low-gradient AS. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Non-invasive measurements of pulse pressure variation and stroke volume variation in anesthetized patients using the Nexfin blood pressure monitor.

Science.gov (United States)

Stens, Jurre; Oeben, Jeroen; Van Dusseldorp, Ab A; Boer, Christa

2016-10-01

Nexfin beat-to-beat arterial blood pressure monitoring enables continuous assessment of hemodynamic indices like cardiac index (CI), pulse pressure variation (PPV) and stroke volume variation (SVV) in the perioperative setting. In this study we investigated whether Nexfin adequately reflects alterations in these hemodynamic parameters during a provoked fluid shift in anesthetized and mechanically ventilated patients. The study included 54 patients undergoing non-thoracic surgery with positive pressure mechanical ventilation. The provoked fluid shift comprised 15° Trendelenburg positioning, and fluid responsiveness was defined as a concomitant increase in stroke volume (SV) >10 %. Nexfin blood pressure measurements were performed during supine steady state, Trendelenburg and supine repositioning. Hemodynamic parameters included arterial blood pressure (MAP), CI, PPV and SVV. Trendelenburg positioning did not affect MAP or CI, but induced a decrease in PPV and SVV by 3.3 ± 2.8 and 3.4 ± 2.7 %, respectively. PPV and SVV returned back to baseline values after repositioning of the patient to baseline. Bland-Altman analysis of SVV and PPV showed a bias of -0.3 ± 3.0 % with limits of agreement ranging from -5.6 to 6.2 %. The SVV was more superior in predicting fluid responsiveness (AUC 0.728) than the PVV (AUC 0.636), respectively. The median bias between PPV and SVV was different for patients younger [-1.5 % (-3 to 0)] or older [+2 % (0-4.75)] than 55 years (P < 0.001), while there were no gender differences in the bias between PPV and SVV. The Nexfin monitor adequately reflects alterations in PPV and SVV during a provoked fluid shift, but the level of agreement between PPV and SVV was low. The SVV tended to be superior over PPV or Eadyn in predicting fluid responsiveness in our population.

Experimental studies for the development of a new method for stroke volume measuring using X-ray videodensitometry

International Nuclear Information System (INIS)

Odenthal, H.J.

1982-01-01

Quantitative videodensitometry was studied with a view to its possible application as a new, non-invasive method of measuring cardiac stroke volume. To begin with, the accuracy of roentgen volumetric measurements was determined. After this, blood volume variations were measured by densitometry in five animal experiments. The findings were compared with the volumes measured by a flowmeter in the pulmonary artery. The total stroke volume was found to be proportional to the difference between the maximum and mean densitometric volume. A comparison between videodensitometry and other non-invasive methods showed that, in a stable circulatory system, the results of videodensitometry are equally reliable as, or even more reliable than, those of the conventional methods. (orig./MG) [de

Know your tools - concordance of different methods for measuring brain volume change after ischemic stroke

Energy Technology Data Exchange (ETDEWEB)

Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew [The University of Melbourne, Departments of Medicine and Neurology, Melbourne Brain Centre rate at The Royal Melbourne Hospital, Parkville, Victoria (Australia); Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M. [The University of Melbourne, Department of Radiology, The Royal Melbourne Hospital, Parkville (Australia); Churilov, Leonid [The University of Melbourne, The Florey Institute of Neurosciences and Mental Health, Parkville (Australia); Parsons, Mark W. [University of Newcastle and Hunter Medical Research Institute, Priority Research Centre for Translational Neuroscience and Mental Health, Newcastle (Australia)

2015-07-15

Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods. Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements. Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions. Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions. (orig.)

Know your tools - concordance of different methods for measuring brain volume change after ischemic stroke

International Nuclear Information System (INIS)

Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew; Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M.; Churilov, Leonid; Parsons, Mark W.

2015-01-01

Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods. Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements. Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions. Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions. (orig.)

Pulmonary diffusing capacity, capillary blood volume, and cardiac output during sustained microgravity

Science.gov (United States)

Prisk, G. K.; Guy, Harold J. B.; Elliott, Ann R.; Deutschman, Robert A., III; West, John B.

1993-01-01

We measured pulmonary diffusing capacity (DL), diffusing capacity per unit lung volume, pulmonary capillary blood volume (Vc), membrane diffusing capacity (Dm), pulmonary capillary blood flow or cardiac output (Qc), and cardiac stroke volume (SV) in four subjects exposed to nine days of microgravity. DL in microgravity was elevated compared with preflight standing values and was higher than preflight supine because of the elevation of both Vc and Dm. The elevation in Vc was comparable to that measured supine in 1 G, but the increase in Dm was in sharp contrast to the supine value. We postulate that, in 0 G, pulmonary capillary blood is evenly distributed throughout the lung, providing for uniform capillary filling, leading to an increase in the surface area available for diffusion. By contrast, in the supine 1-G state, the capillaries are less evenly filled, and although a similar increase in blood volume is observed, the corresponding increase in surface area does not occur. DL and its subdivisions showed no adaptive changes from the first measurement 24 h after the start of 0 G to eight days later. Similarly, there were no trends in the postflight data, suggesting that the principal mechanism of these changes was gravitational. The increase in Dm suggests that subclinical pulmonary edema did not result from exposure to 0 G. Qc was modestly increased inflight and decreased postflight compared with preflight standing. Compared with preflight standing, SV was increased 46 percent inflight and decreased 14 percent in the 1st week postflight. There were temporal changes in Qc and SV during 0 G, with the highest values recorded at the first measurement, 24 h into the flight. The lowest values of Qc and SV occurred on the day of return.

The pathophysiology of the aqueduct stroke volume in normal pressure hydrocephalus: can co-morbidity with other forms of dementia be excluded?

International Nuclear Information System (INIS)

Bateman, Grant A.; Levi, Christopher R.; Wang, Yang; Lovett, Elizabeth C.; Schofield, Peter

2005-01-01

Variable results are obtained from the treatment of normal pressure hydrocephalus (NPH) by shunt insertion. There is a high correlation between NPH and the pathology of Alzheimer's disease (AD) on brain biopsy. There is an overlap between AD and vascular dementia (VaD), suggesting that a correlation exists between NPH and other forms of dementia. This study seeks to (1) understand the physiological factors behind, and (2) define the ability of, the aqueduct stroke volume to exclude dementia co-morbidity. Twenty-four patients from a dementia clinic were classified as having either early AD or VaD on the basis of clinical features, Hachinski score and neuropsychological testing. They were compared with 16 subjects with classical clinical findings of NPH and 12 aged-matched non-cognitively impaired subjects. MRI flow quantification was used to measure aqueduct stroke volume and arterial pulse volume. An arterio-cerebral compliance ratio was calculated from the two volumes in each patient. The aqueduct stroke volume was elevated in all three forms of dementia, with no significant difference noted between the groups. The arterial pulse volume was elevated by 24% in VaD and reduced by 35% in NPH, compared to normal (P=0.05 and P=0.002, respectively), and was normal in AD. There was a spectrum of relative compliance with normal compliance in VaD and reduced compliance in AD and NPH. The aqueduct stroke volume depends on the arterial pulse volume and the relative compliance between the arterial tree and brain. The aqueduct stroke volume cannot exclude significant co-morbidity in NPH. (orig.)

The pathophysiology of the aqueduct stroke volume in normal pressure hydrocephalus: can co-morbidity with other forms of dementia be excluded?

Energy Technology Data Exchange (ETDEWEB)

Bateman, Grant A. [John Hunter Hospital, Department of Medical Imaging, Newcastle (Australia); Levi, Christopher R.; Wang, Yang; Lovett, Elizabeth C. [Hunter Medical Research Institute, Clinical Neurosciences Program, Newcastle (Australia); Schofield, Peter [James Fletcher Hospital, Neuropsychiatry Unit, Newcastle (Australia)

2005-10-01

Variable results are obtained from the treatment of normal pressure hydrocephalus (NPH) by shunt insertion. There is a high correlation between NPH and the pathology of Alzheimer's disease (AD) on brain biopsy. There is an overlap between AD and vascular dementia (VaD), suggesting that a correlation exists between NPH and other forms of dementia. This study seeks to (1) understand the physiological factors behind, and (2) define the ability of, the aqueduct stroke volume to exclude dementia co-morbidity. Twenty-four patients from a dementia clinic were classified as having either early AD or VaD on the basis of clinical features, Hachinski score and neuropsychological testing. They were compared with 16 subjects with classical clinical findings of NPH and 12 aged-matched non-cognitively impaired subjects. MRI flow quantification was used to measure aqueduct stroke volume and arterial pulse volume. An arterio-cerebral compliance ratio was calculated from the two volumes in each patient. The aqueduct stroke volume was elevated in all three forms of dementia, with no significant difference noted between the groups. The arterial pulse volume was elevated by 24% in VaD and reduced by 35% in NPH, compared to normal (P=0.05 and P=0.002, respectively), and was normal in AD. There was a spectrum of relative compliance with normal compliance in VaD and reduced compliance in AD and NPH. The aqueduct stroke volume depends on the arterial pulse volume and the relative compliance between the arterial tree and brain. The aqueduct stroke volume cannot exclude significant co-morbidity in NPH. (orig.)

The effect of endogenously released glucose, insulin, glucagon-like peptide 1, ghrelin on cardiac output, heart rate, stroke volume, and blood pressure

Directory of Open Access Journals (Sweden)

Hlebowicz Joanna

2011-12-01

Full Text Available Abstract Background Ingestion of a meal increases the blood flow to the gastrointestinal organs and affects the heart rate (HR, blood pressure and cardiac output (CO, although the mechanisms are not known. The aim of this study was to evaluate the effect of endogenously released glucose, insulin, glucagon-like peptide 1 (GLP-1, ghrelin on CO, HR, stroke volume (SV, and blood pressure. Methods Eleven healthy men and twelve healthy women ((mean ± SEM aged: 26 ± 0.2 y; body mass index: 21.8 ± 0.1 kg/m2 were included in this study. The CO, HR, SV, systolic and diastolic blood pressure, antral area, gastric emptying rate, and glucose, insulin, GLP-1 and ghrelin levels were measured. Results The CO and SV at 30 min were significantly higher, and the diastolic blood pressure was significantly lower, than the fasting in both men and women (P P = 0.015, r = 0.946, and between ghrelin levels and HR (P = 0.013, r = 0.951 at 110 min. Significant correlations were also found between the change in glucose level at 30 min and the change in systolic blood pressure (P = 0.021, r = -0.681, and the change in SV (P = 0.008, r = -0.748 relative to the fasting in men. The insulin 0-30 min AUC was significantly correlated to the CO 0-30 min AUC (P = 0.002, r = 0.814 in men. Significant correlations were also found between the 0-120 min ghrelin and HR AUCs (P = 0.007, r = 0.966 in men. No statistically significant correlations were seen in women. Conclusions Physiological changes in the levels of glucose, insulin, GLP-1 and ghrelin may influence the activity of the heart and the blood pressure. There may also be gender-related differences in the haemodynamic responses to postprandial changes in hormone levels. The results of this study show that subjects should not eat immediately prior to, or during, the evaluation of cardiovascular interventions as postprandial affects may affect the results, leading to erroneous interpretation of the cardiovascular effects of the

Evaluation of the efficacy of sodium valproate in convulsive status epilepticus following to ıschemic stroke

Directory of Open Access Journals (Sweden)

Hasan Hüseyin Özdemir

2015-04-01

Full Text Available Objective : Convulsive status epilepticus (CSE is very rarely observed after ischaemic stroke. Sodium valproate (SV is one of the agents used in the treatment of CSE, but its role still controversial, and its degree of efficacy in treating CSE that develops following stroke is unclear. Method : We evaluated 19 patients who were treated with intravenous (IV SV (20 mg/kg, 2 mg/kg/h-12h after diazepam. Patients’ modified Rankin scores (mRS, SE types, and changes in biochemical parameters after treatment were assessed. Results : CSE was successfully treated in 12 (63.15% patients. Side effects such as hypotension and allergic reactions were observed in two patients. Refractory SE development was observed in 5 (29.4% patients with high mRS (˃ 3. No significant deterioration in patients’ laboratory evaluations, conducted before and after status, was observed. Conclusion : SV may be safe and effective in the treatment of CSE observed after ischaemic stroke, especially in patients with low mRS.

Relative cerebral blood volume as a marker of durable tissue-at-risk viability in hyperacute ischemic stroke.

Science.gov (United States)

Cortijo, Elisa; Calleja, Ana Isabel; García-Bermejo, Pablo; Mulero, Patricia; Pérez-Fernández, Santiago; Reyes, Javier; Muñoz, Ma Fe; Martínez-Galdámez, Mario; Arenillas, Juan Francisco

2014-01-01

Selection of best responders to reperfusion therapies could be aided by predicting the duration of tissue-at-risk viability, which may be dependant on collateral circulation status. We aimed to identify the best predictor of good collateral circulation among perfusion computed tomography (PCT) parameters in middle cerebral artery (MCA) ischemic stroke and to analyze how early MCA response to intravenous thrombolysis and PCT-derived markers of good collaterals interact to determine stroke outcome. We prospectively studied patients with acute MCA ischemic stroke treated with intravenous thrombolysis who underwent PCT before treatment showing a target mismatch profile. Collateral status was assessed using a PCT source image-based score. PCT maps were quantitatively analyzed. Cerebral blood volume (CBV), cerebral blood flow, and Tmax were calculated within the hypoperfused volume and in the equivalent region of unaffected hemisphere. Occluded MCAs were monitored by transcranial Duplex to assess early recanalization. Main outcome variables were brain hypodensity volume and modified Rankin scale score at day 90. One hundred patients with MCA ischemic stroke imaged by PCT received intravenous thrombolysis, and 68 met all inclusion criteria. A relative CBV (rCBV) >0.93 emerged as the only predictor of good collaterals (odds ratio, 12.6; 95% confidence interval, 2.9-55.9; P=0.001). Early MCA recanalization was associated with better long-term outcome and lower infarct volume in patients with rCBV<0.93, but not in patients with high rCBV. None of the patients with rCBV<0.93 achieved good outcome in absence of early recanalization. High rCBV was the strongest marker of good collaterals and may characterize durable tissue-at-risk viability in hyperacute MCA ischemic stroke.

Rowing increases stroke volume and cardiac output to a greater extent than cycling

Czech Academy of Sciences Publication Activity Database

Horn, P.; Ošťádal, P.; Ošťádal, Bohuslav

2015-01-01

Roč. 64, č. 2 (2015), s. 203-207 ISSN 0862-8408 Institutional support: RVO:67985823 Keywords : cardiac output * cycling * heart rate * stroke volume Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.643, year: 2015

ER Operations Installation of Three FLUTe Soil-Vapor Monitoring Wells (MWL-SV03 MWL-SV04 and MWL-SV05) at the Mixed Waste Landfill.

Energy Technology Data Exchange (ETDEWEB)

Copland, John Robin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-09-01

This installation report describes the May through July 2014 drilling activities performed for the installation of three multi-port soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) at the Mixed Waste Landfill (MWL), which is located at Sandia National Laboratories, New Mexico (SNL/NM). SNL/NM is managed and operated by Sandia Corporation (Sandia), a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy (DOE)/National Nuclear Security Administration. The MWL is designated as Solid Waste Management Unit (SWMU) 76 and is located in Technical Area (TA) III (Figure 1-1). The locations of the three soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) are shown in Figure 1-2

Association between the volume of inpatient rehabilitation therapy and the risk of all-cause and cardiovascular mortality in patients with ischemic stroke.

Science.gov (United States)

Hu, Gwo-Chi; Hsu, Chia-Yu; Yu, Hui-Kung; Chen, Jiann-Perng; Chang, Yu-Ju; Chien, Kuo-Liong

2014-02-01

To investigate the relationship between the volume of inpatient rehabilitation therapy and mortality among patients with acute ischemic stroke, as well as to assess whether the association varies with respect to stroke severity. A retrospective study with a cohort of consecutive patients who had acute ischemic stroke between January 1, 2008, and June 30, 2009. Referral medical center. Adults with acute ischemic stroke (N=1277) who were admitted to a tertiary hospital. Not applicable. Stroke-related mortality. During the median follow-up period of 12.3 months (ranging from January 1, 2008, to December 31, 2009), 163 deaths occurred. Greater volume of rehabilitation therapy was associated with a reduced risk of all-cause and cardiovascular mortality (P for trend rehabilitation volume was associated with a 55% lower risk of all-cause mortality (hazard ratio [HR]=.45; 95% confidence interval [CI], .30-.65) and a 50% lower risk of cardiovascular mortality (HR=.50; 95% CI, .31-.82). The association did not vary with respect to stroke severity (P for interaction = .45 and .73 for all-cause and cardiovascular mortality, respectively). The volume of inpatient rehabilitation therapy and mortality were significantly inversely related in the patients with ischemic stroke. Thus, further programs aimed at promoting greater use of rehabilitation services are warranted. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Mean platelet volume as a risk stratification tool in the Emergency Department for evaluating patients with ischaemic stroke and TIA

International Nuclear Information System (INIS)

Dogan, N.O.; Karakurt, K.

2013-01-01

Objective: To investigate the variations of mean platelet volume in patients with ischaemic cerebrovascular complaints, and to find out its diagnostic utility in an acute setting to help risk stratification in patients with ischaemic stroke and transient ischaemic attacks. Methods: The prospective cross-sectional study was conducted at the Gazi University Hospital, Ankara, Turkey, from November 2009 to June 2010. It comprised 143 consecutive patients of acute ischaemic stroke, 39 patients of transient ischaemic attacks and 60 healthy volunteers. SPSS 13 was used for statistical analysis, and so were t-test, one-way analysis of variance test and correlation analysis. Statistical significance was accepted at p <0.05. Results: Mean platelet volume results were significantly higher in patients with cortical infarction and transient ischaemic attack compared to the control group (p <0.001 and p <0.002). A statistically significant increase was also noted in hospitalised patients when compared with discharged patients from the emergency department (p <0.036). A weak positive correlation was identified between the National Institute of Health Stroke Scores and mean platelet volume levels (r=0.207; p <0.001). A significant relationship was identified between mean platelet volume levels and previous stroke (p <0.005). Conclusion: The measurement of mean platelet volume levels may provide useful diagnostic and prognostic information to emergency physicians caring for patients with transient ischaemic attack and ischaemic stroke. In patients with suspected neurological ischaemic symptoms, high levels may be considered as an atherosclerotic risk factor. (author)

Gray matter volume changes in chronic subcortical stroke: A cross-sectional study

Directory of Open Access Journals (Sweden)

Qingqing Diao

2017-01-01

Full Text Available This study aimed to investigate the effects of lesion side and degree of motor recovery on gray matter volume (GMV difference relative to healthy controls in right-handed subcortical stroke. Structural MRI data were collected in 97 patients with chronic subcortical ischemic stroke and 79 healthy controls. Voxel-wise GMV analysis was used to investigate the effects of lesion side and degree of motor recovery on GMV difference in right-handed chronic subcortical stroke patients. Compared with healthy controls, right-lesion patients demonstrated GMV increase (P < 0.05, voxel-wise false discovery rate correction in the bilateral paracentral lobule (PCL and supplementary motor area (SMA and the right middle occipital gyrus (MOG; while left-lesion patients did not exhibit GMV difference under the same threshold. Patients with complete and partial motor recovery showed similar degree of GMV increase in right-lesion patients. However, the motor recovery was correlated with the GMV increase in the bilateral SMA in right-lesion patients. These findings suggest that there exists a lesion-side effect on GMV difference relative to healthy controls in right-handed patients with chronic subcortical stroke. The GMV increase in the SMA may facilitate motor recovery in subcortical stroke patients.

Precision of gated equilibrium radioventriculography in measuring left ventricular stroke volume

International Nuclear Information System (INIS)

Bourguignon, M.H.; Wise, R.A.; Ehrlich, W.E.; Douglas, K.H.; Camargo, E.E.; Harrison, K.E.; Wagner, H.N. Jr.

1983-01-01

We have demonstrated that relative changes of small amplitude in ventricular stroke volume can be measured accurately in dogs when a fully automated technique for delineation of end diastolic and end systolic region of interest (ROI) is used. Consequently, we expect such a technique to be very sensitive in measuring relative changes of any ventricular quantitative parameter from gated equilibrium radio ventriculography in humans

Normovolemia defined according to cardiac stroke volume in healthy supine humans

DEFF Research Database (Denmark)

Bundgaard-Nielsen, Morten; Jørgensen, Christoffer C; Kehlet, Henrik

2010-01-01

, mean +/- SD), SV was measured by esophageal Doppler before and after fluid administration to evaluate whether SV increases in healthy, non-fasting, supine subjects. Two hundred millilitres of a synthetic colloid (hydroxyethyl starch, HES 130/0.4) was provided and repeated if a >or=10% increment in SV...

Random integration of SV40 in SV40-transformed, immortalized human fibroblasts.

Science.gov (United States)

Hara, H; Kaji, H

1987-02-01

We have studied the relationship between immortalization of SV40-transformed human embryonic fibroblasts and their SV40 integration sites. From several independently transformed cell pools, we have isolated clones which do not harbor unintegrated SV40 DNA. We have analysed whole-cell DNA from these clones, using the Southern blot method. Our results suggest that no specific integration sites in the cellular genome exist which are a prerequisite for the immortalization process. Although some integration sites were found to be predominant in pre-crisis clones, they could not be detected in the post-crisis clones. This suggests that none of these predominating sites is selected for during the crisis period.

Is the standard dose rate for de-contamination, 0.23 mc-Sv/hr, truly 1 mSv/year?

International Nuclear Information System (INIS)

Furuta, Sadaaki

2014-01-01

Examined is the validity of the standard dose rates in the title, which have been additionally defined by Ministry of the Environment (ME) to the measures of Fukushima Nuclear Power Plant Accident. The standard 0.23 mc-Sv/hr is the sum of natural ambient dose rate 0.04 mc-Sv/hr in average of Japan as measured with NaI scintillation surveymeter, plus additional accidental exposure dose 1 mSv/y, which is defined equivalent to 0.19 mc-Sv/hr. Here, the equation of addition 0.04+0.19 mc-Sv/hr is not exactly correct because the unit of each dose value has different means as follows. The natural dose is derived from the value 5.8 mc-R/hr (0.038 mc-Sv/hr, effective dose) of the average national natural dose data (2011) of Ministry of Education, Culture, Sports, Science and Technology. However, if the measurement is done with the surveymeter which practically gives 1 cm dose equivalent, the rate is calculated to be 0.06 mc-Sv/hr. When the Fukushima prefectural natural dose rate 6.4 mc-R/hr is employed, the calculation gives 0.07 mc-Sv/hr. ME defines the additional doses to be 0.19 mc-Sv/hr and 1 mSv/y, which are derived from the calculation: (0.19 mc-Sv/hr x 8 hr outdoor + 0.19 mc-Sv/hr x 0.4 indoor, shielded) x 365 d/y= 1 mSv/y. The dose is assumed to be measurable with the surveymeter (1 cm dose equivalent) and thereby calculation, if the source is mainly "1"3"4Cs and "1"3"7Cs, gives the effective dose of 0.32 mc-Sv/hr to be managed by the meter. As this, the effective dose unit and 1 cm equivalent dose unit are used for calculation of the administrative standard dose rate of 1 mSv/y, which should be recognized by both radiological experts and administration for the explanation to general public. (T.T.)

Titin is a candidate gene for stroke volume response to endurance training: the HERITAGE Family Study.

Science.gov (United States)

Rankinen, Tuomo; Rice, Treva; Boudreau, Anik; Leon, Arthur S; Skinner, James S; Wilmore, Jack H; Rao, D C; Bouchard, Claude

2003-09-29

A genome-wide linkage scan for endurance training-induced changes in submaximal exercise stroke volume (DeltaSV50) in the HERITAGE Family Study revealed two chromosomal regions (2q31-q32 and 10p11.2) with at least suggestive evidence of linkage among white families. Here we report a further characterization of the quantitative trait locus (QTL) in chromosome 2q31 and provide evidence that titin (TTN) is likely a candidate gene involved. The original linkage was detected with two markers (D2S335 and D2S1391), and the QTL covered approximately 25 million base pairs (Mb). We added 12 microsatellite markers resulting in an average marker density of one marker per 2.3 Mb. The evidence of linkage increased from P = 0.006 to P = 0.0002 and 0.00002 in the multi- and single-point analyses, respectively. The strongest evidence of linkage was seen with two markers in and near the TTN gene. Transmission/disequilibrium test (TDT) with the same marker set provided evidence for association with one of the TTN markers (D2S385; P = 0.004). TTN is a major contributor to the elasticity of cardiomyocytes and a key regulator of the Frank-Starling mechanism. Since TTN is the largest gene in the human genome, the challenge is to identify the DNA sequence variants contributing to the interindividual differences in cardiac adaptation to endurance training.

Simvastatin (SV) metabolites in mouse tissues

International Nuclear Information System (INIS)

Duncan, C.A.; Vickers, S.

1990-01-01

SV, a semisynthetic analog of lovastatin, is hydrolyzed in vivo to its hydroxy acid (SVA), a potent inhibitor of HMG CoA reductase (HR). Thus SV lowers plasma cholesterol. SV is a substrate for mixed function oxidases whereas SVA undergoes lactonization and β-oxidation. Male CD-1 mice were dosed orally with a combination of ( 14 C)SV and ( 3 H)SVA at 25 mg/kg of each, bled and killed at 0.5, 2 and 4 hours. Labeled SV, SVA, 6'exomethylene SV (I), 6'CH 2 OH-SV (II), 6'COOH-SV (III) and a β-oxidized metabolite (IV) were assayed in liver, bile, kidneys, testes and plasma by RIDA. Levels of potential and active HR inhibitors in liver were 10 to 40 fold higher than in other tissues. II and III, in which the configuration at 6' is inverted, may be 2 metabolites of I. Metabolites I-III are inhibitors of HR in their hydroxy acid forms. Qualitatively ( 14 C)SV and ( 3 H)SVA were metabolized similarly (consistent with their proposed interconversion). However 3 H-SVA, I-III (including hydroxy acid forms) achieved higher concentrations than corresponding 14 C compounds (except in gall bladder bile). Major radioactive metabolites in liver were II-IV (including hydroxy acid forms). These metabolites have also been reported in rat tissues. In bile a large fraction of either label was unidentified polar metabolites. The presence of IV indicated that mice (like rats) are not good models for SV metabolism in man

Reperfusion is a more accurate predictor of follow-up infarct volume than recanalization: a proof of concept using CT in acute ischemic stroke patients.

Science.gov (United States)

Soares, Bruno P; Tong, Elizabeth; Hom, Jason; Cheng, Su-Chun; Bredno, Joerg; Boussel, Loic; Smith, Wade S; Wintermark, Max

2010-01-01

The purpose of this study was to compare recanalization and reperfusion in terms of their predictive value for imaging outcomes (follow-up infarct volume, infarct growth, salvaged penumbra) and clinical outcome in acute ischemic stroke patients. Twenty-two patients admitted within 6 hours of stroke onset were retrospectively included in this study. These patients underwent a first stroke CT protocol including CT-angiography (CTA) and perfusion-CT (PCT) on admission, and similar imaging after treatment, typically around 24 hours, to assess recanalization and reperfusion. Recanalization was assessed by comparing arterial patency on admission and posttreatment CTAs; reperfusion, by comparing the volumes of CBV, CBF, and MTT abnormality on admission and posttreatment PCTs. Collateral flow was graded on the admission CTA. Follow-up infarct volume was measured on the discharge noncontrast CT. The groups of patients with reperfusion, no reperfusion, recanalization, and no recanalization were compared in terms of imaging and clinical outcomes. Reperfusion (using an MTT reperfusion index >75%) was a more accurate predictor of follow-up infarct volume than recanalization. Collateral flow and recanalization were not accurate predictors of follow-up infarct volume. An interaction term was found between reperfusion and the volume of the admission penumbra >50 mL. Our study provides evidence that reperfusion is a more accurate predictor of follow-up infarct volume in acute ischemic stroke patients than recanalization. We recommend an MTT reperfusion index >75% to assess therapy efficacy in future acute ischemic stroke trials that use perfusion-CT.

In-treatment stroke volume predicts cardiovascular risk in hypertension

DEFF Research Database (Denmark)

Lønnebakken, Mai T; Gerdts, Eva; Boman, Kurt

2011-01-01

, the prespecified primary study endpoint, was assessed in Cox regression analysis using data from baseline and annual follow-up visits in 855 patients during 4.8 years of randomized losartan-based or atenolol-based treatment in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiography...... with higher risk of cardiovascular events {hazard ratio 1.69 per 1 SD (6 ml/m2.04) lower stroke volume [95% confidence interval (CI) 1.35–2.11], P secondary model also independent of stress-corrected midwall shortening......, hence, adds information on cardiovascular risk in treated hypertensive patients beyond assessment of left ventricular structure alone....

Age and gender specific normal values of left ventricular mass, volume and function for gradient echo magnetic resonance imaging: a cross sectional study

International Nuclear Information System (INIS)

Cain, Peter A; Ahl, Ragnhild; Hedstrom, Erik; Ugander, Martin; Allansdotter-Johnsson, Ase; Friberg, Peter; Arheden, Hakan

2009-01-01

Knowledge about age-specific normal values for left ventricular mass (LVM), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) by cardiac magnetic resonance imaging (CMR) is of importance to differentiate between health and disease and to assess the severity of disease. The aims of the study were to determine age and gender specific normal reference values and to explore the normal physiological variation of these parameters from adolescence to late adulthood, in a cross sectional study. Gradient echo CMR was performed at 1.5 T in 96 healthy volunteers (11–81 years, 50 male). Gender-specific analysis of parameters was undertaken in both absolute values and adjusted for body surface area (BSA). Age and gender specific normal ranges for LV volumes, mass and function are presented from the second through the eighth decade of life. LVM, ESV and EDV rose during adolescence and declined in adulthood. SV and EF decreased with age. Compared to adult females, adult males had higher BSA-adjusted values of EDV (p = 0.006) and ESV (p < 0.001), similar SV (p = 0.51) and lower EF (p = 0.014). No gender differences were seen in the youngest, 11–15 year, age range. LV volumes, mass and function vary over a broad age range in healthy individuals. LV volumes and mass both rise in adolescence and decline with age. EF showed a rapid decline in adolescence compared to changes throughout adulthood. These findings demonstrate the need for age and gender specific normal ranges for clinical use

One-step simultaneous detection of Ureaplasma parvum and genotypes SV1, SV3 and SV6 from clinical samples using PlexPCR technology.

Science.gov (United States)

Payne, M S; Furfaro, L L; Tucker, R; Tan, L Y; Mokany, E

2017-08-01

Ureaplasma spp. are associated with preterm birth. In recent times, it has become apparent that Ureaplasma parvum, but not Ureaplasma urealyticum, is of most relevance. We recently demonstrated this in Australian pregnant women and using high-resolution melt (HRM) PCR, further showed that U. parvum genotype SV6 was of particular significance. However, our assay was unable to identify multiple genotypes in the same sample, required a separate species-level qPCR for low titre samples and was not ideal for diagnostic laboratories due to the nature of HRM PCR result interpretation. Consequently, our current study developed a novel, one-step PlexPCR assay capable of detecting U. parvum and genotypes SV1, SV3 and SV6 in a single reaction directly from clinical samples. We then validated this using vaginal swab DNA from our Australian cohort of pregnant women. The PlexPCR was highly sensitive, detecting all targets to between 0.4 × 10 -5  ng DNA (SV3) and 0.4 × 10 -6  ng DNA (U. parvum, SV1 and SV6). Compared to our HRM PCR, the PlexPCR defined genotype distribution in all seven cases previously reported as 'mixed', and detected another eight cases where multiple genotypes (two) were present in samples previously reported as single genotypes using HRM PCR. Ureaplasma spp. have been associated with prematurity for decades, however, only a minority of studies have examined this beyond the genus level. In those that have, Ureaplasma parvum has been strongly associated with preterm birth. We recently demonstrated this in Australian women and further showed that U. parvum genotype SV6 was of particular significance. Our PlexPCR assay allows rapid detection and concurrent genotyping of U. parvum in clinical samples and may be of particular interest to obstetricians, particularly those caring for women at a high risk of preterm birth, and any other disease phenotypes where U. parvum is of interest. © 2017 The Authors. Letters in Applied Microbiology published by John

Commentaar op art. 563 Sv

NARCIS (Netherlands)

Knoops, G.G.J.; van Laanen, F.; Melai, A.L.; Groenhuijsen, M.S.

2004-01-01

Schrijvers verschaffen een wetenschappelijk commentaar op art. 563 Sv, betreffende de tenuitvoerlegging van andere straffen dan de bij art. 562 Sv bedoelde straffen ingeval van een veroordeelde wiens geestvermogens ziekelijk zijn gestoord.

CT angiography and CT perfusion improve prediction of infarct volume in patients with anterior circulation stroke

Energy Technology Data Exchange (ETDEWEB)

Seeters, Tom van; Schaaf, Irene C. van der; Dankbaar, Jan Willem; Horsch, Alexander D.; Niesten, Joris M.; Luitse, Merel J.A.; Mali, Willem P.T.M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Biessels, Geert Jan; Kappelle, L.J. [University Medical Center Utrecht, Department of Neurology, Brain Center Rudolf Magnus, Utrecht (Netherlands); Majoie, Charles B.L.M. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Vos, Jan Albert [St. Antonius Hospital, Department of Radiology, Nieuwegein (Netherlands); Schonewille, Wouter J. [St. Antonius Hospital, Department of Neurology, Nieuwegein (Netherlands); Walderveen, Marianne A.A. van [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Wermer, Marieke J.H. [Leiden University Medical Center, Department of Neurology, Leiden (Netherlands); Duijm, Lucien E.M. [Catharina Hospital, Department of Radiology, Eindhoven (Netherlands); Keizer, Koos [Catharina Hospital, Department of Neurology, Eindhoven (Netherlands); Bot, Joseph C.J. [VU University Medical Center, Department of Radiology, Amsterdam (Netherlands); Visser, Marieke C. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Lugt, Aad van der [Erasmus MC University Medical Center, Department of Radiology, Rotterdam (Netherlands); Dippel, Diederik W.J. [Erasmus MC University Medical Center, Department of Neurology, Rotterdam (Netherlands); Kesselring, F.O.H.W. [Rijnstate Hospital, Department of Radiology, Arnhem (Netherlands); Hofmeijer, Jeannette [Rijnstate Hospital, Department of Neurology, Arnhem (Netherlands); Lycklama a Nijeholt, Geert J. [Medical Center Haaglanden, Department of Radiology, The Hague (Netherlands); Boiten, Jelis [Medical Center Haaglanden, Department of Neurology, The Hague (Netherlands); Rooij, Willem Jan van [St. Elisabeth Hospital, Department of Radiology, Tilburg (Netherlands); Kort, Paul L.M. de [St. Elisabeth Hospital, Department of Neurology, Tilburg (Netherlands); Roos, Yvo B.W.E.M. [Academic Medical Center, Department of Neurology, Amsterdam (Netherlands); Meijer, Frederick J.A. [Radboud University Medical Center, Department of Radiology, Nijmegen (Netherlands); Pleiter, C.C. [St. Franciscus Hospital, Department of Radiology, Rotterdam (Netherlands); Graaf, Yolanda van der [University Medical Center Utrecht, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Collaboration: Dutch acute stroke study (DUST) investigators

2016-04-15

We investigated whether baseline CT angiography (CTA) and CT perfusion (CTP) in acute ischemic stroke could improve prediction of infarct presence and infarct volume on follow-up imaging. We analyzed 906 patients with suspected anterior circulation stroke from the prospective multicenter Dutch acute stroke study (DUST). All patients underwent baseline non-contrast CT, CTA, and CTP and follow-up non-contrast CT/MRI after 3 days. Multivariable regression models were developed including patient characteristics and non-contrast CT, and subsequently, CTA and CTP measures were added. The increase in area under the curve (AUC) and R{sup 2} was assessed to determine the additional value of CTA and CTP. At follow-up, 612 patients (67.5 %) had a detectable infarct on CT/MRI; median infarct volume was 14.8 mL (interquartile range (IQR) 2.8-69.6). Regarding infarct presence, the AUC of 0.82 (95 % confidence interval (CI) 0.79-0.85) for patient characteristics and non-contrast CT was improved with addition of CTA measures (AUC 0.85 (95 % CI 0.82-0.87); p < 0.001) and was even higher after addition of CTP measures (AUC 0.89 (95 % CI 0.87-0.91); p < 0.001) and combined CTA/CTP measures (AUC 0.89 (95 % CI 0.87-0.91); p < 0.001). For infarct volume, adding combined CTA/CTP measures (R{sup 2} = 0.58) was superior to patient characteristics and non-contrast CT alone (R{sup 2} = 0.44) and to addition of CTA alone (R{sup 2} = 0.55) or CTP alone (R{sup 2} = 0.54; all p < 0.001). In the acute stage, CTA and CTP have additional value over patient characteristics and non-contrast CT for predicting infarct presence and infarct volume on follow-up imaging. These findings could be applied for patient selection in future trials on ischemic stroke treatment. (orig.)

Three-dimensional whole-brain perfused blood volume imaging with multimodal CT for evaluation of acute ischaemic stroke

International Nuclear Information System (INIS)

Lu, J.; Zhang, M.; Cao, Y.; Ma, Q.; Chen, J.; Ji, X.; Li, K.

2011-01-01

Aim: To determine the diagnostic value of integrating three-dimensional perfused blood volume (3D PBV) with multimodal computed tomography (CT) [non-enhanced CT (NECT), CT perfusion (CTP), and CT angiography (CTA)] in acute ischaemic stroke. Materials and methods: NECT, CTP, and CTA were performed in 25 acute ischaemic stroke patients. The ischaemia detection rate of 3D PBV was compared with the results of baseline NECT and CTP. The correlation of ischaemic lesion volume between 3D PBV, CTP images, and follow-up NECT were analysed. Results: NECT demonstrated ischaemic signs in 12 of 25 patients with proven infarction. CTP maps of cerebral blood flow (CBF), cerebral blood volume (CBV), and time to peak (TTP) all demonstrated perfusion deficits in 21 of 25 patients. However, 3D PBV demonstrated perfusion deficits in all of the 25 patients. Among the 25 patients, a strong correlation was found between PBV and the follow-up NECT infarct (r = 0.858). The correlation between CTP and the follow-up NECT infarct as following: CBF (r = 0.718), CBV (r = 0.785), and TTP (r = 0.569). In 14 thrombolytic patients, strong correlation was found between the ischaemic volume on 3D PBV and follow-up NECT (r = 0.798). Conclusion: In acute stroke patients, the combination of 3D PBV and multimodal CT (NECT, CTP, and CTA) can improve the detection rate of ischaemia and enable assessment of the full extent of ischaemia, which correlates well with follow-up NECT.

Whole-brain perfusion CT using a toggling table technique to predict final infarct volume in acute ischemic stroke.

Science.gov (United States)

Schrader, I; Wilk, D; Jansen, O; Riedel, C

2013-09-01

To evaluate how accurately final infarct volume in acute ischemic stroke can be predicted with perfusion CT (PCT) using a 64-MDCT unit and the toggling table technique. Retrospective analysis of 89 patients with acute ischemic stroke who underwent CCT, CT angiography (CTA) and PCT using the "toggling table" technique within the first three hours after symptom onset. In patients with successful thrombolytic therapy (n = 48) and in those without effective thrombolytic therapy (n = 41), the infarct volume and the volume of the penumbra on PCT were compared to the infarct size on follow-up images (CT or MRI) performed within 8 days. The feasibility of complete infarct volume prediction by 8 cm cranio-caudal coverage was evaluated. The correlation between the volume of hypoperfusion on PCT defined by cerebral blood volume reduction and final infarct volume was strongest in patients with successful thrombolytic therapy with underestimation of the definite infarct volume by 8.5 ml on average. The CBV map had the greatest prognostic value. In patients without successful thrombolytic therapy, the final infarct volume was overestimated by 12.1 ml compared to the MTT map on PCT. All infarcts were detected completely. There were no false-positive or false-negative results. Using PCT and the "toggling table" technique in acute stroke patients is helpful for the rapid and accurate quantification of the minimal final infarct and is therefore a prognostic parameter which has to be evaluated in further studies to assess its impact on therapeutic decision. ▶ Using PCT and the “toggling table technique” allows accurate quantification of the infarct core and penumbra. ▶ It is possible to record dynamic perfusion parameters quickly and easily of almost the entire supratentorial brain volume on a 64-slice MDCT unit. ▶ The technique allows identification of those patients who could profit from thrombolytic therapy outside the established time intervals. © Georg Thieme Verlag

Assessment of Collateral Status by Dynamic CT Angiography in Acute MCA Stroke: Timing of Acquisition and Relationship with Final Infarct Volume

NARCIS (Netherlands)

van den Wijngaard, I. R.; Holswilder, G.; Wermer, M. J. H.; Boiten, J.; Algra, A.; Dippel, D. W. J.; Dankbaar, J. W.; Velthuis, B. K.; Boers, A. M. M.; Majoie, C. B. L. M.; van Walderveen, M. A. A.

2016-01-01

Dynamic CTA is a promising technique for visualization of collateral filling in patients with acute ischemic stroke. Our aim was to describe collateral filling with dynamic CTA and assess the relationship with infarct volume at follow-up. We selected patients with acute ischemic stroke due to

Biological activity of SV40 DNA

International Nuclear Information System (INIS)

Abrahams, P.J.

1978-01-01

This thesis deals with a study on the biological activity of SV40 DNA. The transforming activity of SV40 DNA and DNA fragments is investigated in order to define as precisely as possible the area of the viral genome that is involved in the transformation. The infectivity of SV40 DNA is used to study the defective repair mechanisms of radiation damages of human xeroderma pigmentosum cells. (C.F.)

Right Hemisphere Grey Matter Volume and Language Functions in Stroke Aphasia

Directory of Open Access Journals (Sweden)

Sladjana Lukic

2017-01-01

Full Text Available The role of the right hemisphere (RH in recovery from aphasia is incompletely understood. The present study quantified RH grey matter (GM volume in individuals with chronic stroke-induced aphasia and cognitively healthy people using voxel-based morphometry. We compared group differences in GM volume in the entire RH and in RH regions-of-interest. Given that lesion site is a critical source of heterogeneity associated with poststroke language ability, we used voxel-based lesion symptom mapping (VLSM to examine the relation between lesion site and language performance in the aphasic participants. Finally, using results derived from the VLSM as a covariate, we evaluated the relation between GM volume in the RH and language ability across domains, including comprehension and production processes both at the word and sentence levels and across spoken and written modalities. Between-subject comparisons showed that GM volume in the RH SMA was reduced in the aphasic group compared to the healthy controls. We also found that, for the aphasic group, increased RH volume in the MTG and the SMA was associated with better language comprehension and production scores, respectively. These data suggest that the RH may support functions previously performed by LH regions and have important implications for understanding poststroke reorganization.

Inter- and intra-rater reproducibility of semiautomatic determination of volume parameters in cardiac magnetic resonance imaging

International Nuclear Information System (INIS)

Trieb, Thomas; Glodny, Bernhard; Scheiblhofer, Martin; Wolf, Christian; Metzler, Bernhard; Pachinger, Otmar; Jaschke, Werner R.; Schocke, Michael F.H.

2008-01-01

Purpose: The purpose of this study was to evaluate inter- and intra-rater reproducibility in volume assessment using cardiac magnetic resonance imaging (CMRI). Methods: Twenty-five healthy volunteers and 106 patients were included into this retrospective study and received CMRI. The patients were divided in three groups (group I, 80 patients with arrhythmia; group II, 20 patients with cardiomyopathy; group III, 6 patients after correction of septum defects). Therefore, the images were semiautomatically segmented by an experienced and an unexperienced radiologists. The analysis of end-diastolic volume (EDV), end-systolic volume (ESV) and stroke volume (SV) as well as ejection fraction (EF) and myocardial mass (MM) were performed twice by an experienced and an unexperienced radiologists. The intra-class correlation coefficients (ICC) were determined for the evaluation of inter- and intra-rater variance. Results: The intra-rater reproducibility for determination of EF, ESV, EDV and MM was excellent with ICCs ranging from 0.88 to 0.99 (all p < 0.001). The inter-observer reproducibility for these parameters was also excellent with ICCs ranging from 0.91 to 0.98 (all p < 0.001). The assessment of the SV showed an excellent intra-rater agreement with ICCs of 0.96 and 0.92 (both p < 0.001), but only a moderate ICC for the inter-rater reproducibility (0.54, p < 0.001). Conclusions: Our study shows that assessment of cardiac volumes can be performed on CMRIs with an excellent reproducibility by both experienced and unexperienced investigators

Structural MRI markers of brain aging early after ischemic stroke.

Science.gov (United States)

Werden, Emilio; Cumming, Toby; Li, Qi; Bird, Laura; Veldsman, Michele; Pardoe, Heath R; Jackson, Graeme; Donnan, Geoffrey A; Brodtmann, Amy

2017-07-11

To examine associations between ischemic stroke, vascular risk factors, and MRI markers of brain aging. Eighty-one patients (mean age 67.5 ± 13.1 years, 31 left-sided, 61 men) with confirmed first-ever (n = 66) or recurrent (n = 15) ischemic stroke underwent 3T MRI scanning within 6 weeks of symptom onset (mean 26 ± 9 days). Age-matched controls (n = 40) completed identical testing. Multivariate regression analyses examined associations between group membership and MRI markers of brain aging (cortical thickness, total brain volume, white matter hyperintensity [WMH] volume, hippocampal volume), normalized against intracranial volume, and the effects of vascular risk factors on these relationships. First-ever stroke was associated with smaller hippocampal volume ( p = 0.025) and greater WMH volume ( p = 0.004) relative to controls. Recurrent stroke was in turn associated with smaller hippocampal volume relative to both first-ever stroke ( p = 0.017) and controls ( p = 0.001). These associations remained significant after adjustment for age, sex, education, and, in stroke patients, infarct volume. Total brain volume was not significantly smaller in first-ever stroke patients than in controls ( p = 0.056), but the association became significant after further adjustment for atrial fibrillation ( p = 0.036). Cortical thickness and brain volumes did not differ as a function of stroke type, infarct volume, or etiology. Brain structure is likely to be compromised before ischemic stroke by vascular risk factors. Smaller hippocampal and total brain volumes and increased WMH load represent proxies for underlying vascular brain injury. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

Clinical course of brain stroke in the persons exposed to ionizing radiation under the production conditions

International Nuclear Information System (INIS)

Bouchmanov, A.

2000-01-01

The purpose was to study the risk factors and clinical course of brain strokes in professionally exposed workers being employed in plutonium production in comparison with a control group. The method and materials of study -clinical supervision and clinical database creation on 162 cases of brain stroke (128 males and 34 females) developed among professionally exposed workers. Age of patient varied from 21 to 68 years (in average -51.6 y.). The control group consisted of patients with the same diagnosis, worked on the same enterprise, but non-exposed to radiation. Data on the totally accumulated dose of external gamma radiation were received on the base of the individual dosimeters (from 0.1 cSv to 52 cSv, in average about 13 cSv); the plutonium-239 body content was estimated accordingly to the level of urine radionuclide excretion (from 0.4 kBq to 1.6 kBq, in average about 0.33 kBq). Muscle's hypertinsion and pathological great-toe reflexes in paretic legs and hands, hemianopsia, impressive and ataxic aphasia prevailed in the patients with ischemic brain strokes in system of internal carotid artery, exposed to radiation. The changes of muscle's tension, ataxia and nystagmus were marked more often in the professionals with ischemic brain strokes in system of vertebrobasilar artery. The illness proceeded more easy and with smaller frequency of frustration of consciousness and algesthesia, irrespective of a type ischemic brain strokes in the people exposed to ionizing radiation, than in patients of non-irradiated group. It was found that the arterial hypertension appeared to be the main risk factor for the brain stroke in both groups of patients (in 81.48% and 91.15% of cases). There was no marked differences in significance of risk factors and in main clinical parameters of various types of ischemic brain strokes among the patients professionally exposed to radiation in comparison with a control group. (author)

Clinical course of brain stroke in the persons exposed to ionizing radiation under the production conditions

Energy Technology Data Exchange (ETDEWEB)

Bouchmanov, A. [State Research Center of Russia, Moscow (Russian Federation). Inst. of Biophysics

2000-05-01

The purpose was to study the risk factors and clinical course of brain strokes in professionally exposed workers being employed in plutonium production in comparison with a control group. The method and materials of study -clinical supervision and clinical database creation on 162 cases of brain stroke (128 males and 34 females) developed among professionally exposed workers. Age of patient varied from 21 to 68 years (in average -51.6 y.). The control group consisted of patients with the same diagnosis, worked on the same enterprise, but non-exposed to radiation. Data on the totally accumulated dose of external gamma radiation were received on the base of the individual dosimeters (from 0.1 cSv to 52 cSv, in average about 13 cSv); the plutonium-239 body content was estimated accordingly to the level of urine radionuclide excretion (from 0.4 kBq to 1.6 kBq, in average about 0.33 kBq). Muscle's hypertinsion and pathological great-toe reflexes in paretic legs and hands, hemianopsia, impressive and ataxic aphasia prevailed in the patients with ischemic brain strokes in system of internal carotid artery, exposed to radiation. The changes of muscle's tension, ataxia and nystagmus were marked more often in the professionals with ischemic brain strokes in system of vertebrobasilar artery. The illness proceeded more easy and with smaller frequency of frustration of consciousness and algesthesia, irrespective of a type ischemic brain strokes in the people exposed to ionizing radiation, than in patients of non-irradiated group. It was found that the arterial hypertension appeared to be the main risk factor for the brain stroke in both groups of patients (in 81.48% and 91.15% of cases). There was no marked differences in significance of risk factors and in main clinical parameters of various types of ischemic brain strokes among the patients professionally exposed to radiation in comparison with a control group. (author)

Effect of pre-stroke use of ACE inhibitors on ischemic stroke severity

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Caplan Louis

2005-06-01

Full Text Available Abstract Background Recent trials suggest that angiotensin-converting enzyme inhibitors (ACEI are effective in prevention of ischemic stroke, as measured by reduced stroke incidence. We aimed to compare stroke severity between stroke patients who were taking ACEI before their stroke onset and those who were not, to examine the effects of pretreatment with ACEI on ischemic stroke severity. Methods We retrospectively studied 126 consecutive patients presenting within 24 hours of ischemic stroke onset, as confirmed by diffusion-weighted magnetic resonance imaging (DWI. We calculated the NIHSS score at presentation, as the primary measure of clinical stroke severity, and categorized stroke severity as mild (NIHSS [less than or equal to] 7, moderate (NIHSS 8–13 or severe (NIHSS [greater than or equal to] 14. We analyzed demographic data, risk-factor profile, blood pressure (BP and medications on admissions, and determined stroke mechanism according to TOAST criteria. We also measured the volumes of admission diffusion- and perfusion-weighted (DWI /PWI magnetic resonance imaging lesions, as a secondary measure of ischemic tissue volume. We compared these variables among patients on ACEI and those who were not. Results Thirty- three patients (26% were on ACE-inhibitors. The overall median baseline NIHSS score was 5.5 (range 2–21 among ACEI-treated patients vs. 9 (range 1–36 in non-ACEI patients (p = 0.036. Patients on ACEI prior to their stroke had more mild and less severe strokes, and smaller DWI and PWI lesion volumes compared to non-ACEI treated patients. However, none of these differences were significant. Predictably, a higher percentage of patients on ACEI had a history of heart failure (p = 0.03. Age, time-to-imaging or neurological evaluation, risk-factor profile, concomitant therapy with lipid lowering, other antihypertensives or antithrombotic agents, or admission BP were comparable between the two groups. Conclusion Our results

Automatic extraction of left ventricular mass and volumes using parametric images from non-ECG-gated 15O-water PET/CT

DEFF Research Database (Denmark)

Nordström, J; Harms, Hans; Lubberink, Mark

of the present study was to investigate the feasibility of measuring LV geometry using dynamic 15O-water PET/CT without ECG-gating. Methods: Parametric images of MBF, perfusable tissue fraction (PTF) and LV blood pool were generated automatically using kinetic modelling. Segmentation of the LV wall using PTF......Introduction: 15O-water positron emission tomography (PET) is considered the gold standard for non-invasive quantification of myocardial blood flow (MBF). It has been shown to identify patients with significant coronary artery disease (CAD) with high accuracy. Hypertrophy with or without dilatation...... combined to measure stroke volume (SV=EDV-ESV) and ejection fraction (EF=SV/EDV). Accuracy was determined by comparing PET to cardiac magnetic resonance (CMR) in 30 asymptomatic patients with high grade LV regurgitation (group A). Precision was determined as inter-observer variation in group...

Comparison between biventricular cine MRI and MR flow quantification in ascending aorta and pulmonary outflow tract for the assessment of intracardial shunt volumes

International Nuclear Information System (INIS)

Rominger, M.B.; Kluge, A.; Bachmann, G.F.; Dinkel, H.P.

2002-01-01

Purpose: Comparison between biventricular volumetric measurements and flow measurements in ascending aorta (Ao) and pulmonary outflow tract (Pu) for quantification of intracardial shunts, and evaluation of the combination of biventricular cine MRI with flow measurements for the assessment of RV and LV heart failure and valvular regurgitation (VR). Material and Methods: In 24 patients, right (RV) and left (LV) ventricular volumetric and flow measurements were performed in the Ao and Pu to assess the ratio of RV stroke volume (SV) or, respectively, pulmonary SV to LV SV or, respectively, systemic aortic SV (Qp/Qs). 34 patients without echocardiographically proven shunt or VR served as control group for measurement accuracy. Left-to-right shunt ratios were calculated from RV and LV SV, Pu and Ao SV, Pu and LV SV, and RV and Ao SV. Left ventricular VR was calculated by the difference of LV SV and Ao SV, and right ventricular VR by the difference of RV SV and Pu SV. Global systolic function was evaluated by biventricular cine MRI. Results: Intracardial shunts with Qp/Qs>1,16 can be quantified by flow measurements in Ao and Pu. Using biventricular volumetric measurements in cases without VR, requires a Qp/Qs>1.21. 17 of 18 intracardiac shunts were identified on MRI, and all 8 hemodynamically significant shunts were quantitatively confirmed. The diagnosis of complete shunt closure or absent shunt was correctly made in all 6 cases RV EF reduction was found in 6 of 24 patients. LV EF reduction was also found in 6 of 24 patients. Conclusion: Flow measurements in Ao and Pu are more accurate than biventricular cine MRI for the assessment of Qp/Qs ratios. Flow measurements in Ao and Pu combined with biventricular cine MRI enables the quantification of hemodynamic significant shunts, higher grade VR and biventricular global systolic function with a single examination. (orig.) [de

Early Change in Stroke Size Performs Best in Predicting Response to Therapy.

Science.gov (United States)

Simpkins, Alexis Nétis; Dias, Christian; Norato, Gina; Kim, Eunhee; Leigh, Richard

2017-01-01

Reliable imaging biomarkers of response to therapy in acute stroke are needed. The final infarct volume and percent of early reperfusion have been used for this purpose. Early fluctuation in stroke size is a recognized phenomenon, but its utility as a biomarker for response to therapy has not been established. This study examined the clinical relevance of early change in stroke volume and compared it with the final infarct volume and percent of early reperfusion in identifying early neurologic improvement (ENI). Acute stroke patients, enrolled between 2013 and 2014 with serial magnetic resonance imaging (MRI) scans (pretreatment baseline, 2 h post, and 24 h post), who received thrombolysis were included in the analysis. Early change in stroke volume, infarct volume at 24 h on diffusion, and percent of early reperfusion were calculated from the baseline and 2 h MRI scans were compared. ENI was defined as ≥4 point decrease in National Institutes of Health Stroke Scales within 24 h. Logistic regression models and receiver operator characteristics analysis were used to compare the efficacy of 3 imaging biomarkers. Serial MRIs of 58 acute stroke patients were analyzed. Early change in stroke volume was significantly associated with ENI by logistic regression analysis (OR 0.93, p = 0.048) and remained significant after controlling for stroke size and severity (OR 0.90, p = 0.032). Thus, for every 1 mL increase in stroke volume, there was a 10% decrease in the odds of ENI, while for every 1 mL decrease in stroke volume, there was a 10% increase in the odds of ENI. Neither infarct volume at 24 h nor percent of early reperfusion were significantly associated with ENI by logistic regression. Receiver-operator characteristic analysis identified early change in stroke volume as the only biomarker of the 3 that performed significantly different than chance (p = 0.03). Early fluctuations in stroke size may represent a more reliable biomarker for response to therapy than the

Quantitating aortic regurgitation by cardiovascular magnetic resonance: significant variations due to slice location and breath holding

International Nuclear Information System (INIS)

Chaturvedi, Abhishek; Hamilton-Craig, Christian; Cawley, Peter J.; Maki, Jeffrey H.; Mitsumori, Lee M.; Otto, Catherine M.

2016-01-01

Compare variability in flow measurements by phase contrast MRI, performed at different locations in the aorta and pulmonary artery (PA) using breath-held (BH) and free-breathing (FB) sequences. Fifty-seven patients with valvular heart disease, confirmed by echocardiography, were scanned using BH technique at 3 locations in the ascending aorta (SOV = sinus of Valsalva, STJ = sinotubular junction, ASC = ascending aorta at level of right pulmonary artery) and 2 locations in PA. Single FB measurement was obtained at STJ for aorta. Obtained metrics (SV = stroke volume, FV = forward volume, BV = backward volume, RF = regurgitant fraction) were evaluated separately for patients with aortic regurgitation (AR, n = 31) and mitral regurgitation (n = 26). No difference was noted between the two measurements in the PA. Significant differences were noted in measured SV at different aortic locations. SV measurements obtained at ASC correlated best with the measurements obtained in the PA. Strongest correlation of AR was measured at the STJ. Measurements of flow volumes by phase contrast MRI differ depending on slice location. When using stroke volumes to calculate pulmonary to systemic blood flow ratio (Qp/Qs), ASC should be used. For quantifying aortic regurgitation, measurement should be obtained at STJ. (orig.)

Surface and volume three-dimensional displays of Tc-99m HMPAO brain SPECT images in stroke patients with three-head gamma camera

International Nuclear Information System (INIS)

Shih, W.J.; Slevin, J.T.; Schleenbaker, R.E.; Mills, B.J.; Magoun, S.L.; Ryo, U.Y.

1991-01-01

This paper evaluates volume and surface 3D displays in Tc-99m HMPAO brain SPECT imaging in stroke patients. Using a triple-head gamma camera interfaced with a 64-bit supercomputer, 20 patients with stroke were studied. Each patient was imaged 30-60 minutes after an intravenous injection of 20 mCi of Tc-99m HMPAO. SPECT images as well as planar images were routinely obtained; volume and surface 3D display then proceeded, with the process requiring 5-10 minutes. Volume and surface 3D displays show the brain from all angles; thus the location and extension of lesion(s) in the brain are much easier to appreciate. While a cerebral lesion(s) was more clearly delineated by surface 3D imaging, crossed cerebellar diaschisis in seven patients was clearly exhibited with volume 3D but not with surface 3D imaging. Volume and surface 3D displays enhance continuity of structures and understanding of spatial relationships

Association between acute statin therapy, survival, and improved functional outcome after ischemic stroke: the North Dublin Population Stroke Study.

LENUS (Irish Health Repository)

2011-04-01

Statins improve infarct volume and neurological outcome in animal stroke models. We investigated the relationship between statin therapy and ischemic stroke outcome in the North Dublin Population Stroke Study.

Age and gender specific normal values of left ventricular mass, volume and function for gradient echo magnetic resonance imaging: a cross sectional study

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Allansdotter-Johnsson Ase

2009-01-01

Full Text Available Abstract Background Knowledge about age-specific normal values for left ventricular mass (LVM, end-diastolic volume (EDV, end-systolic volume (ESV, stroke volume (SV and ejection fraction (EF by cardiac magnetic resonance imaging (CMR is of importance to differentiate between health and disease and to assess the severity of disease. The aims of the study were to determine age and gender specific normal reference values and to explore the normal physiological variation of these parameters from adolescence to late adulthood, in a cross sectional study. Methods Gradient echo CMR was performed at 1.5 T in 96 healthy volunteers (11–81 years, 50 male. Gender-specific analysis of parameters was undertaken in both absolute values and adjusted for body surface area (BSA. Results Age and gender specific normal ranges for LV volumes, mass and function are presented from the second through the eighth decade of life. LVM, ESV and EDV rose during adolescence and declined in adulthood. SV and EF decreased with age. Compared to adult females, adult males had higher BSA-adjusted values of EDV (p = 0.006 and ESV (p Conclusion LV volumes, mass and function vary over a broad age range in healthy individuals. LV volumes and mass both rise in adolescence and decline with age. EF showed a rapid decline in adolescence compared to changes throughout adulthood. These findings demonstrate the need for age and gender specific normal ranges for clinical use.

Multiphasic perfusion CT in acute middle cerebral artery ischemic stroke: prediction of final infarct volume and correlation with clinical outcome

International Nuclear Information System (INIS)

Yi, Chin A; Na, Dong Gyu; Ryoo, Jae Wook; Moon, Chan Hong; Byun, Hong Sik; Roh, Hong Gee; Moon, Won Jin; Lee, Kwang Ho; Lee, Soo Joo

2002-01-01

To assess the utility of multiphasic perfusion CT in the prediction of final infarct volume, and the relationship between lesion volume revealed by CT imaging and clinical outcome in acute ischemic stroke patients who have not undergone thrombolytic therapy. Thirty-five patients underwent multiphasic perfusion CT within six hours of stroke onset. After baseline unenhanced helical CT scanning, contrast-enhanced CT scans were obtained 20, 34, 48, and 62 secs after the injection of 90 mL contrast medium at a rate of 3 mL/sec. CT peak and total perfusion maps were obtained from serial CT images, and the initial lesion volumes revealed by CT were compared with final infarct volumes and clinical scores. Overall, the lesion volumes seen on CT peak perfusion maps correlated most strongly with final infarct volumes (R2=0.819, p<0.001, slope of regression line=1.016), but individual data showed that they were less than final infarct volume in 31.4% of patients. In those who showed early clinical improvement (n=6), final infarct volume tended to be overestimated by CT peak perfusion mapping and only on total perfusion maps was there significant correlation between lesion volume and final infarct volume (R2=0.854, p=0.008). The lesion volumes depicted by CT maps showed moderate correlation with baseline clinical scores and clinical outcomes (R=0.445-0.706, p≤0.007). CT peak perfusion maps demonstrate strong correlation between lesion volume and final infarct volume, and accurately predict final infarct volume in about two-thirds of the 35 patients. The lesion volume seen on CT maps shows moderate correlation with clinical outcome

Oltar Sv. Jeronima u crkvi Sv. Šime u Zadru i radionica Bettamelli

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Bojan Goja

2012-12-01

Full Text Available U radu se na temelju arhivskih podataka govori o oltaru Sv. Jeronima u crkvi Sv. Šime u Zadru. Od ranije se zna da je oltar dala podići i o njegovu se uređenju brinula bratovština hrvatskih i albanskih vojnika (Croatti a cavallo i Soldati Albanesi u službi Mletačke Republike, osnovana 1675. godine u Zadru. Novim je arhivskim istraživanjima utvrđeno da je dana 26. rujna 1694. godine bratovština odobrila izdatak u iznosu od 200 srebrnih dukata, namijenjenih venecijanskim klesarima braći Bettamelli kao predujam za izradu oltara te da su radovi na njegovu podizanju započeti u travnju 1696. godine. Na temelju zapisa o gradnji oltara iznijeta je pretpostavka da se grb na istočnom pilastru stipesa oltara, ranije povezivan s predstavnicima obitelji Civran, odnosi na zadarskog plemića i istaknutog zapovjednika u mletačkoj vojsci, Šimuna Fanfognu (Zadar, 7. travnja 1663. - Lendinara, 6. ožujka 1707. koji je obavljao i dužnost prokuratora oltara. Brojni radovi na uređenju oltara i kapele Sv. Jeronima obavljani su i tijekom čitavog 18. stoljeća, a na njima su bili uposleni brojni mjesni majstori različitih struka: graditelji Antonio Piovesana (1742. i Antonio Bernardini (1789., oltarist Girolamo Picco (1756., marangon Domenico Tomaselli (1743., kovač Antonelli (1744. te zlatari Zorzi Cullisich (1738., Nicolò Giurovich (1752. i Giuseppe Rado (1755.. Donose se još neke zanimljivosti vezane uz uređenje oltara i djelovanje bratovštine Sv. Jeronima.

Effect of fluid loading with normal saline and 6% hydroxyethyl starch on stroke volume variability and left ventricular volume

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Kanda H

2015-09-01

Full Text Available Hirotsugu Kanda,1 Yuji Hirasaki,2 Takafumi Iida,1 Megumi Kanao,1 Yuki Toyama,1 Takayuki Kunisawa,1 Hiroshi Iwasaki,11Department of Anesthesiology and Critical Care Medicine, Asahikawa Medical University, Asahikawa, 2Department of Anatomy, The Jikei University Graduate School of Medicine, Tokyo, JapanPurpose: The aim of this clinical trial was to investigate changes in stroke volume variability (SVV and left ventricular end-diastolic volume (LVEDV after a fluid bolus of crystalloid or colloid using real-time three-dimensional transesophageal echocardiography (3D-TEE and the Vigileo-FloTrac™ system.Materials and methods: After obtaining Institutional Review Board approval, and informed consent from the research participants, 22 patients undergoing scheduled peripheral vascular bypass surgery were enrolled in the study. The patients were randomly assigned to receive 500 mL of hydroxyethyl starch (HES; HES group, n=11 or normal saline (Saline group, n=11 for fluid replacement therapy. SVV was measured using the Vigileo-FloTrac system. LVEDV, stroke volume, and cardiac output were measured by 3D-TEE. The measurements were performed over 30 minutes before and after the fluid bolus in both groups.Results: SVV significantly decreased after fluid bolus in both groups (HES group, 14.7%±2.6% to 6.9%±2.7%, P<0.001; Saline group, 14.3%±3.9% to 8.8%±3.1%, P<0.001. LVEDV significantly increased after fluid loading in the HES group (87.1±24.0 mL to 99.9±27.2 mL, P<0.001, whereas no significant change was detected in the Saline group (88.8±17.3 mL to 91.4±17.6 mL, P>0.05. Stroke volume significantly increased after infusion in the HES group (50.6±12.5 mL to 61.6±19.1 mL, P<0.01 but not in the Saline group (51.6±13.4 mL to 54.1±12.8 mL, P>0.05. Cardiac output measured by 3D-TEE significantly increased in the HES group (3.5±1.1 L/min to 3.9±1.3 L/min, P<0.05, whereas no significant change was seen in the Saline group (3.4±1.1 L/min to 3.3±1.0 L

Svømmehaller og krav til energieffektivitet

OpenAIRE

Øen, Martin Nerhus

2010-01-01

Svømmehaller er en spesiell bygningstype, som med høy innendørs temperatur og luftfuktighet, skiller seg fra andre bygninger som boliger og kontorbygg. Den høye innetemperaturen, forbruket av varmtvann, og fordampning fra svømmebassenget fører til et stort energiforbruk. Svømmehaller er ikke gitt egne krav i Teknisk forskrift til plan- og bygningsloven (TEK), til tross for at energiforbruket kan være tre ganger høyere enn kravene gitt for idrettshaller. Målet med denne rapporten er å finne fo...

The use of LiDCO based fluid management in patients undergoing hip fracture surgery under spinal anaesthesia: Neck of femur optimisation therapy - targeted stroke volume (NOTTS: study protocol for a randomized controlled trial

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Moran Chris G

2011-09-01

Full Text Available Abstract Background Approximately 70,000 patients/year undergo surgery for repair of a fractured hip in the United Kingdom. This is associated with 30-day mortality of 9% and survivors have a considerable length of acute hospital stay postoperatively (median 26 days. Use of oesophageal Doppler monitoring to guide intra-operative fluid administration in hip fracture repair has previously been associated with a reduction in hospital stay of 4-5 days. Most hip fracture surgery is now performed under spinal anaesthesia. Oesophageal Doppler monitoring may be unreliable in the presence of spinal anaesthesia and most patients would not tolerate the probes. An alternative method of guiding fluid administration (minimally-invasive arterial pulse contour analysis has been shown to reduce length of stay in high-risk surgical patients but has never been studied in hip fracture surgery. Methods Single-centre randomised controlled parallel group trial. Randomisation by website using computer generated concealed tables. Setting: University hospital in UK. Participants: 128 patients with acute primary hip fracture listed for operative repair under spinal anaesthesia and aged > 65 years. Intervention: Stroke volume guided intra-operative fluid management. Continuous measurement of SV recorded by a calibrated cardiac output monitor (LiDCOplus. Maintenance fluid and 250 ml colloid boluses given to achieve sustained 10% increases in stroke volume. Control group: fluid administration at the responsible (blinded anaesthetist's discretion. The intervention terminates at the end of the surgical procedure and post-operative fluid management is at the responsible anaesthetist's discretion. Primary outcome: length of acute hospital stay is determined by a blinded team of clinicians. Secondary outcomes include number of complications and total cost of care. Funding NIHR/RfPB: PB-PG-0407-13073. Trial registration number Trial registration: Current Controlled Trials ISRCTN

Levetiracetam reverses synaptic deficits produced by overexpression of SV2A.

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Amy Nowack

Full Text Available Levetiracetam is an FDA-approved drug used to treat epilepsy and other disorders of the nervous system. Although it is known that levetiracetam binds the synaptic vesicle protein SV2A, how drug binding affects synaptic functioning remains unknown. Here we report that levetiracetam reverses the effects of excess SV2A in autaptic hippocampal neurons. Expression of an SV2A-EGFP fusion protein produced a ∼1.5-fold increase in synaptic levels of SV2, and resulted in reduced synaptic release probability. The overexpression phenotype parallels that seen in neurons from SV2 knockout mice, which experience severe seizures. Overexpression of SV2A also increased synaptic levels of the calcium-sensor protein synaptotagmin, an SV2-binding protein whose stability and trafficking are regulated by SV2. Treatment with levetiracetam rescued normal neurotransmission and restored normal levels of SV2 and synaptotagmin at the synapse. These results indicate that changes in SV2 expression in either direction impact neurotransmission, and suggest that levetiracetam may modulate SV2 protein interactions.

Noninvasive pulse pressure variation and stroke volume variation to predict fluid responsiveness at multiple thresholds : a prospective observational study

NARCIS (Netherlands)

Vos, Jaap Jan; Poterman, Marieke; Papineau Salm, Pieternel; Van Amsterdam, Kai; Struys, Michel M. R. F.; Scheeren, Thomas W. L.; Kalmar, Alain F.

2015-01-01

Pulse pressure variation (PPV) and stroke volume variation (SVV) are dynamic preload variables that can be measured noninvasively to assess fluid responsiveness (FR) in anesthetized patients with mechanical ventilation. Few studies have examined the effectiveness of predicting FR according to the

Evaluation of left atrial function by multidetector computed tomography before left atrial radiofrequency-catheter ablation: Comparison of a manual and automated 3D volume segmentation method

International Nuclear Information System (INIS)

Wolf, Florian; Ourednicek, Petr; Loewe, Christian; Richter, Bernhard; Goessinger, Heinz David; Gwechenberger, Marianne; Plank, Christina; Schernthaner, Ruediger Egbert; Toepker, Michael; Lammer, Johannes; Feuchtner, Gudrun M.

2010-01-01

Introduction: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT). Methods and materials: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated. Results: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7 ml, 93 ml, 34.7 ml, 27.1% by the automated, and 122.7 ml, 89.9 ml, 32.8 ml, 26.3% by the manual method with no significant difference (p > 0.05) and high Pearsons correlation coefficients (r = 0.94, r = 0.94, r = 0.82 and r = 0.85, p < 0.0001), respectively. The automated method was significantly faster (p < 0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p < 0.0001). Conclusions: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.

Evaluation of left atrial function by multidetector computed tomography before left atrial radiofrequency-catheter ablation: Comparison of a manual and automated 3D volume segmentation method

Energy Technology Data Exchange (ETDEWEB)

Wolf, Florian, E-mail: florian.wolf@meduniwien.ac.a [Department of Radiology, Medical University of Vienna, Vienna (Austria); Ourednicek, Petr [Philips Medical Systems, Prague (Czech Republic); Loewe, Christian [Department of Radiology, Medical University of Vienna, Vienna (Austria); Richter, Bernhard; Goessinger, Heinz David; Gwechenberger, Marianne [Department of Cardiology, Medical University of Vienna, Vienna (Austria); Plank, Christina; Schernthaner, Ruediger Egbert; Toepker, Michael; Lammer, Johannes [Department of Radiology, Medical University of Vienna, Vienna (Austria); Feuchtner, Gudrun M. [Department of Radiology, Innsbruck Medical University, Innsbruck (Austria); Institute of Diagnostic Radiology, University Hospital Zurich (Switzerland)

2010-08-15

Introduction: The purpose of this study was to compare a manual and automated 3D volume segmentation tool for evaluation of left atrial (LA) function by 64-slice multidetector-CT (MDCT). Methods and materials: In 33 patients with paroxysmal atrial fibrillation a MDCT scan was performed before radiofrequency-catheter ablation. Atrial function (minimal volume (LAmin), maximal volume (LAmax), stroke volume (SV), ejection fraction (EF)) was evaluated by two readers using a manual and an automatic tool and measurement time was evaluated. Results: Automated LA volume segmentation failed in one patient due to low LA enhancement (103HU). Mean LAmax, LAmin, SV and EF were 127.7 ml, 93 ml, 34.7 ml, 27.1% by the automated, and 122.7 ml, 89.9 ml, 32.8 ml, 26.3% by the manual method with no significant difference (p > 0.05) and high Pearsons correlation coefficients (r = 0.94, r = 0.94, r = 0.82 and r = 0.85, p < 0.0001), respectively. The automated method was significantly faster (p < 0.001). Interobserver variability was low for both methods with Pearson's correlation coefficients between 0.98 and 0.99 (p < 0.0001). Conclusions: Evaluation of LA volume and function with 64-slice MDCT is feasible with a very low interobserver variability. The automatic method is as accurate as the manual method but significantly less time consuming permitting a routine use in clinical practice before RF-catheter ablation.

Evaluation of right ventricular volumes measured by magnetic resonance imaging

DEFF Research Database (Denmark)

Møgelvang, J; Stubgaard, M; Thomsen, C

1988-01-01

stroke volume was calculated as the difference between end-diastolic and end-systolic volume and compared to left ventricular stroke volume and to stroke volume determined simultaneously by a classical indicator dilution technique. There was good agreement between right ventricular stroke volume......Right ventricular volumes were determined in 12 patients with different levels of right and left ventricular function by magnetic resonance imaging (MRI) using an ECG gated multisection technique in planes perpendicular to the diastolic position of the interventricular septum. Right ventricular...... determined by MRI and by the indicator dilution method and between right and left ventricular stroke volume determined by MRI. Thus, MRI gives reliable values not only for left ventricular volumes, but also for right ventricular volumes. By MRI it is possible to obtain volumes from both ventricles...

Stroke volume variation compared with pulse pressure variation and cardiac index changes for prediction of fluid responsiveness in mechanically ventilated patients

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Randa Aly Soliman

2015-04-01

Conclusions: Baseline stroke volume variation ⩾8.15% predicted fluid responsiveness in mechanically ventilated patients with acute circulatory failure. The study also confirmed the ability of pulse pressure variation to predict fluid responsiveness.

Does prostate brachytherapy treat the seminal vesicles? A dose-volume histogram analysis of seminal vesicles in patients undergoing combined PD-103 prostate implantation and external beam irradiation

International Nuclear Information System (INIS)

Stock, Richard G.; Lo, Yeh-Chi; Gaildon, Mohamoud; Stone, Nelson N.

1999-01-01

Purpose: Combined brachytherapy of the prostate and external beam irradiation (EBRT) of the prostate and seminal vesicles (SV) is becoming a popular treatment for high-risk prostate cancer. Dose-volume histogram (DVH) analysis of the SV in patients undergoing this treatment was performed to determine the dose distribution to the SV and the adequacy of this treatment in patients with potential SV involvement. Methods and Materials: Twenty-five consecutive patients were treated with a Pd-103 implant of the prostate alone and 45 Gy of EBRT to the prostate and SV. Attempts were not made to implant the SV but seeds were routinely placed at the junction of the prostate and SV. All patients underwent CT-based post implant dosimetric analysis 1 month after implantation. As part of this analysis, DVH were generated for the prostate and total SV volume (SVT). In addition, the SV was divided into 6-mm-thick volumes identified as SV1, SV2, SV3, SV4, and SV5 starting from the junction of the prostate and SV and extending distally. DVH were also generated for these structures. Delivered dose was defined as the D90 (dose delivered to 90% of the organ on DVH). Results: The median volumes in cc of the prostate, SVT, SV1, SV2, SV3, SV4, and SV5 were 34.33, 9.75, 2.7, 3.48, 2.92, 3.18, and 1.96 respectively. The SVT contained from 0-9 seeds (median 2). There was little dose delivered to the SVT and SV volumes from the implanted prostate. The median D90 values for the prostate, SVT, SV1, SV2, SV3, SV4, and SV5 were 8615 cGy, 675 cGy, 3100 cGy, 1329 cGy, 553 cGy, 246 cGy, and 67 cGy, respectively. The dose delivered to the prostate covered small percentages of SV. The percents of SV volumes covered by the prostate D90 were 11, 35, 3.3, 0, 0, and 0 for SVT, SV1, SV2, SV3, SV4, and SV5, respectively. Conclusions: DVH analysis of the SV reveals that dose generated from an implanted prostate contributes little to the SV. Those patients at high risk for SV involvement may be under treated

Cardiac Output and Performance during a Marathon Race in Middle-Aged Recreational Runners

OpenAIRE

Billat, Véronique L.; Petot, Hélène; Landrain, Morgan; Meilland, Renaud; Koralsztein, Jean Pierre; Mille-Hamard, Laurence

2012-01-01

Purpose. Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). Methods. We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maxima...

Stroke Location Is an Independent Predictor of Cognitive Outcome.

Science.gov (United States)

Munsch, Fanny; Sagnier, Sharmila; Asselineau, Julien; Bigourdan, Antoine; Guttmann, Charles R; Debruxelles, Sabrina; Poli, Mathilde; Renou, Pauline; Perez, Paul; Dousset, Vincent; Sibon, Igor; Tourdias, Thomas

2016-01-01

On top of functional outcome, accurate prediction of cognitive outcome for stroke patients is an unmet need with major implications for clinical management. We investigated whether stroke location may contribute independent prognostic value to multifactorial predictive models of functional and cognitive outcomes. Four hundred twenty-eight consecutive patients with ischemic stroke were prospectively assessed with magnetic resonance imaging at 24 to 72 hours and at 3 months for functional outcome using the modified Rankin Scale and cognitive outcome using the Montreal Cognitive Assessment (MoCA). Statistical maps of functional and cognitive eloquent regions were derived from the first 215 patients (development sample) using voxel-based lesion-symptom mapping. We used multivariate logistic regression models to study the influence of stroke location (number of eloquent voxels from voxel-based lesion-symptom mapping maps), age, initial National Institutes of Health Stroke Scale and stroke volume on modified Rankin Scale and MoCA. The second part of our cohort was used as an independent replication sample. In univariate analyses, stroke location, age, initial National Institutes of Health Stroke Scale, and stroke volume were all predictive of poor modified Rankin Scale and MoCA. In multivariable analyses, stroke location remained the strongest independent predictor of MoCA and significantly improved the prediction compared with using only age, initial National Institutes of Health Stroke Scale, and stroke volume (area under the curve increased from 0.697-0.771; difference=0.073; 95% confidence interval, 0.008-0.155). In contrast, stroke location did not persist as independent predictor of modified Rankin Scale that was mainly driven by initial National Institutes of Health Stroke Scale (area under the curve going from 0.840 to 0.835). Similar results were obtained in the replication sample. Stroke location is an independent predictor of cognitive outcome (MoCA) at 3

Stroke etiology and collaterals: atheroembolic strokes have greater collateral recruitment than cardioembolic strokes.

Science.gov (United States)

Rebello, L C; Bouslama, M; Haussen, D C; Grossberg, J A; Dehkharghani, S; Anderson, A; Belagaje, S R; Bianchi, N A; Grigoryan, M; Frankel, M R; Nogueira, R G

2017-06-01

Chronic hypoperfusion from athero-stenotic lesions is thought to lead to better collateral recruitment compared to cardioembolic strokes. It was sought to compare collateral flow in stroke patients with atrial fibrillation (AF) versus stroke patients with cervical atherosclerotic steno-occlusive disease (CASOD). This was a retrospective review of a prospectively collected endovascular database. Patients with (i) anterior circulation large vessel occlusion stroke, (ii) pre-treatment computed tomography angiography (CTA) and (iii) intracranial embolism from AF or CASOD were included. CTA collateral patterns were evaluated and categorized into two groups: absent/poor collaterals (CTA collateral score 0-1) versus moderate/good collaterals (CTA collateral score 2-4). CT perfusion was also utilized for baseline core volume and evaluation of infarct growth. A total of 122 patients fitted the inclusion criteria, of whom 88 (72%) had AF and 34 (27%) CASOD. Patients with AF were older (P Collateral scores were lower in the AF group (P = 0.01) with patients having poor collaterals in 28% of cases versus 9% in the CASOD group (P = 0.03). Mortality rates (20% vs. 0%; P = 0.02) were higher in the AF patients whilst rates of any parenchymal hemorrhage (6% vs. 26%; P collaterals (odds ratio 4.70; 95% confidence interval 1.17-18.79; P = 0.03). Atheroembolic strokes seem to be associated with better collateral flow compared to cardioembolic strokes. This may in part explain the worse outcomes of AF-related stroke. © 2017 EAN.

Paradoxical centrally increased diffusivity in perinatal arterial ischemic stroke

International Nuclear Information System (INIS)

Stence, Nicholas V.; Mirsky, David M.; Deoni, Sean C.L.; Armstrong-Wells, Jennifer

2016-01-01

Restricted diffusion on acute MRI is the diagnostic standard for perinatal arterial ischemic stroke. In a subset of children with perinatal arterial ischemic stroke, primarily those with large infarct volumes, we noted a core of centrally increased diffusivity with a periphery of restricted diffusion. Given the paradoxical diffusion-weighted imaging (DWI) appearance observed in some children with perinatal arterial ischemic stroke, we sought to determine its significance and hypothesized that: (1) centrally increased diffusivity is associated with larger infarcts in perinatal arterial ischemic stroke and (2) this tissue is irreversibly injured (infarcted). We reviewed all perinatal arterial ischemic stroke cases in a prospective cohort study from Aug. 1, 2000, to Jan. 1, 2012. Infarct volumes were measured by drawing regions of interest around the periphery of the area of restricted diffusion on DWI. The Mann-Whitney U test was used to compare means between groups. Of 25 eligible cases, centrally increased diffusivity was seen in 4 (16%). Cases with centrally increased diffusivity had larger average infarct volumes (mean 117,182 mm 3 vs. 36,995 mm 3 ; P = 0.008), higher average apparent diffusion coefficient (ADC) values in the infarct core (1,679 x 10 -6 mm 2 /s vs. 611 x 10 -6 mm 2 /s, P < 0.0001), and higher ADC ratio (1.2 vs. 0.5, P < 0.0001). At last clinical follow-up, children with perinatal arterial ischemic stroke and centrally increased diffusivity were more often treated for ongoing seizures (75% vs. 0%; P < 0.001) than those without. Centrally increased diffusivity was associated with larger stroke volume and the involved tissue was confirmed to be infarcted on follow-up imaging. Radiologists should be aware of this unusual appearance of perinatal arterial ischemic stroke in order to avoid underestimating infarct volume or making an incorrect early diagnosis. (orig.)

Paradoxical centrally increased diffusivity in perinatal arterial ischemic stroke

Energy Technology Data Exchange (ETDEWEB)

Stence, Nicholas V.; Mirsky, David M.; Deoni, Sean C.L. [University of Colorado Anschutz School of Medicine, Department of Radiology, Aurora, CO (United States); Children' s Hospital Colorado, Department of Radiology, Aurora, CO (United States); Armstrong-Wells, Jennifer [University of Colorado Anschutz School of Medicine, Department of Pediatrics (Neurology) and OB/GYN, Aurora, CO (United States); University of Colorado Hemophilia and Thrombosis Center, Aurora, CO (United States)

2016-01-15

Restricted diffusion on acute MRI is the diagnostic standard for perinatal arterial ischemic stroke. In a subset of children with perinatal arterial ischemic stroke, primarily those with large infarct volumes, we noted a core of centrally increased diffusivity with a periphery of restricted diffusion. Given the paradoxical diffusion-weighted imaging (DWI) appearance observed in some children with perinatal arterial ischemic stroke, we sought to determine its significance and hypothesized that: (1) centrally increased diffusivity is associated with larger infarcts in perinatal arterial ischemic stroke and (2) this tissue is irreversibly injured (infarcted). We reviewed all perinatal arterial ischemic stroke cases in a prospective cohort study from Aug. 1, 2000, to Jan. 1, 2012. Infarct volumes were measured by drawing regions of interest around the periphery of the area of restricted diffusion on DWI. The Mann-Whitney U test was used to compare means between groups. Of 25 eligible cases, centrally increased diffusivity was seen in 4 (16%). Cases with centrally increased diffusivity had larger average infarct volumes (mean 117,182 mm{sup 3} vs. 36,995 mm{sup 3}; P = 0.008), higher average apparent diffusion coefficient (ADC) values in the infarct core (1,679 x 10{sup -6} mm{sup 2}/s vs. 611 x 10{sup -6} mm{sup 2}/s, P < 0.0001), and higher ADC ratio (1.2 vs. 0.5, P < 0.0001). At last clinical follow-up, children with perinatal arterial ischemic stroke and centrally increased diffusivity were more often treated for ongoing seizures (75% vs. 0%; P < 0.001) than those without. Centrally increased diffusivity was associated with larger stroke volume and the involved tissue was confirmed to be infarcted on follow-up imaging. Radiologists should be aware of this unusual appearance of perinatal arterial ischemic stroke in order to avoid underestimating infarct volume or making an incorrect early diagnosis. (orig.)

Autonomic Functions Associated with Blood Pressure Regulation and Orthostatic Performance in Women

National Research Council Canada - National Science Library

Convertino, Victor

1997-01-01

... in men and women to test the hypothesis that greater orthostatic intolerance in women would be associated with impairment of specific mechanisms of blood pressure regulation. Heart rate (HR), stroke volume (SV), cardiac output (Q...

Herniation despite Decompressive Hemicraniectomy in Large Hemispherical Ischemic Strokes.

Science.gov (United States)

Hinduja, Archana; Samant, Rohan; Feng, Dongxia; Hannawi, Yousef

2018-02-01

Despite decompressive hemicraniectomy (DHC), progressive herniation resulting in death has been reported following middle cerebral artery (MCA) strokes. We aimed to determine the surgical parameters measured on brain computed tomography (CT) scan that are associated with progressive herniation despite DHC in large MCA strokes. Retrospective chart review of medical records of patients with malignant hemispheric infarction who underwent DHC for cerebral edema was performed. Infarct volume was calculated on CT scans obtained within 24 hours of ictus. Radiological parameters of craniectomy bone flap size, brain volume protruding out of the skull, adequate centering of the craniectomy over the stroke bed, and the infarct volume outside the craniectomy bed (volume not centered [VNC]) were measured on the postoperative brain CT. Of 41 patients who underwent DHC, 7 had progressive herniation leading to death. Radiographic parameters significantly associated with progressive herniation included insufficient centering of craniectomy bed on the stroke bed (P = .03), VNC (P = .011), additional anterior cerebral artery infarction (P = .047), and smaller craniectomy length (P = .05). Multivariate logistic regression analysis for progressive herniation using craniectomy length and VNC as independent variables demonstrated that a higher VNC was significantly associated with progressive herniation despite surgery (P = .029). In large MCA strokes, identification of large infarct volume outside the craniectomy bed was associated with progressive herniation despite surgery. These results will need to be verified in larger prospective studies. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Automatic extraction of forward stroke volume using dynamic PET/CT

DEFF Research Database (Denmark)

Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik Stubkjær

2015-01-01

Background The aim of this study was to develop and validate an automated method for extracting forward stroke volume (FSV) using indicator dilution theory directly from dynamic positron emission tomography (PET) studies for two different tracers and scanners. Methods 35 subjects underwent...... a dynamic 11 C-acetate PET scan on a Siemens Biograph TruePoint-64 PET/CT (scanner I). In addition, 10 subjects underwent both dynamic 15 O-water PET and 11 C-acetate PET scans on a GE Discovery-ST PET/CT (scanner II). The left ventricular (LV)-aortic time-activity curve (TAC) was extracted automatically...... from PET data using cluster analysis. The first-pass peak was isolated by automatic extrapolation of the downslope of the TAC. FSV was calculated as the injected dose divided by the product of heart rate and the area under the curve of the first-pass peak. Gold standard FSV was measured using phase...

SV-AUTOPILOT: optimized, automated construction of structural variation discovery and benchmarking pipelines.

Science.gov (United States)

Leung, Wai Yi; Marschall, Tobias; Paudel, Yogesh; Falquet, Laurent; Mei, Hailiang; Schönhuth, Alexander; Maoz Moss, Tiffanie Yael

2015-03-25

Many tools exist to predict structural variants (SVs), utilizing a variety of algorithms. However, they have largely been developed and tested on human germline or somatic (e.g. cancer) variation. It seems appropriate to exploit this wealth of technology available for humans also for other species. Objectives of this work included: a) Creating an automated, standardized pipeline for SV prediction. b) Identifying the best tool(s) for SV prediction through benchmarking. c) Providing a statistically sound method for merging SV calls. The SV-AUTOPILOT meta-tool platform is an automated pipeline for standardization of SV prediction and SV tool development in paired-end next-generation sequencing (NGS) analysis. SV-AUTOPILOT comes in the form of a virtual machine, which includes all datasets, tools and algorithms presented here. The virtual machine easily allows one to add, replace and update genomes, SV callers and post-processing routines and therefore provides an easy, out-of-the-box environment for complex SV discovery tasks. SV-AUTOPILOT was used to make a direct comparison between 7 popular SV tools on the Arabidopsis thaliana genome using the Landsberg (Ler) ecotype as a standardized dataset. Recall and precision measurements suggest that Pindel and Clever were the most adaptable to this dataset across all size ranges while Delly performed well for SVs larger than 250 nucleotides. A novel, statistically-sound merging process, which can control the false discovery rate, reduced the false positive rate on the Arabidopsis benchmark dataset used here by >60%. SV-AUTOPILOT provides a meta-tool platform for future SV tool development and the benchmarking of tools on other genomes using a standardized pipeline. It optimizes detection of SVs in non-human genomes using statistically robust merging. The benchmarking in this study has demonstrated the power of 7 different SV tools for analyzing different size classes and types of structural variants. The optional merge

Prediction of infarction and reperfusion in stroke by flow- and volume-weighted collateral signal in MR angiography.

Science.gov (United States)

Ernst, M; Forkert, N D; Brehmer, L; Thomalla, G; Siemonsen, S; Fiehler, J; Kemmling, A

2015-02-01

In proximal anterior circulation occlusive strokes, collateral flow is essential for good outcome. Collateralized vessel intensity in TOF- and contrast-enhanced MRA is variable due to different acquisition methods. Our purpose was to quantify collateral supply by using flow-weighted signal in TOF-MRA and blood volume-weighted signal in contrast-enhanced MRA to determine each predictive contribution to tissue infarction and reperfusion. Consecutively (2009-2013), 44 stroke patients with acute proximal anterior circulation occlusion met the inclusion criteria with TOF- and contrast-enhanced MRA and penumbral imaging. Collateralized vessels in the ischemic hemisphere were assessed by TOF- and contrast-enhanced MRA using 2 methods: 1) visual 3-point collateral scoring, and 2) collateral signal quantification by an arterial atlas-based collateral index. Collateral measures were tested by receiver operating characteristic curve and logistic regression against 2 imaging end points of tissue-outcome: final infarct volume and percentage of penumbra saved. Visual collateral scores on contrast-enhanced MRA but not TOF were significantly higher in patients with good outcome. Visual collateral scoring on contrast-enhanced MRA was the best rater-based discriminator for final infarct volume 50% (area under the curve, 0.67; P = .04). Atlas-based collateral index of contrast-enhanced MRA was the overall best independent discriminator for final infarct volume of collateral index combining the signal of TOF- and contrast-enhanced MRA was the overall best discriminator for effective reperfusion (percentage of penumbra saved >50%; area under the curve, 0.89; P collateral assessment, TOF- and contrast-enhanced MRA both contain predictive signal information for penumbral reperfusion. This could improve risk stratification in further studies. © 2015 by American Journal of Neuroradiology.

Stroke subtype classification by geometrical descriptors of lesion shape.

Directory of Open Access Journals (Sweden)

Bastian Cheng

Full Text Available Inference of etiology from lesion pattern in acute magnetic resonance imaging is valuable for management and prognosis of acute stroke patients. This study aims to assess the value of three-dimensional geometrical lesion-shape descriptors for stroke-subtype classification, specifically regarding stroke of cardioembolic origin.Stroke Etiology was classified according to ASCOD in retrospectively selected patients with acute stroke. Lesions were segmented on diffusion-weighed datasets, and descriptors of lesion shape quantified: surface area, sphericity, bounding box volume, and ratio between bounding box and lesion volume. Morphological measures were compared between stroke subtypes classified by ASCOD and between patients with embolic stroke of cardiac and non-cardiac source.150 patients (mean age 77 years; 95% CI, 65-80 years; median NIHSS 6, range 0-22 were included. Group comparison of lesion shape measures demonstrated that lesions caused by small-vessel disease were smaller and more spherical compared to other stroke subtypes. No significant differences of morphological measures were detected between patients with cardioembolic and non-cardioembolic stroke.Stroke lesions caused by small vessel disease can be distinguished from other stroke lesions based on distinctive morphological properties. However, within the group of embolic strokes, etiology could not be inferred from the morphology measures studied in our analysis.

Automatic extraction of forward stroke volume using dynamic PET/CT

DEFF Research Database (Denmark)

Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik

Background: Dynamic PET can be used to extract forward stroke volume (FSV) by the indicator dilution principle. The technique employed can be automated and is in theory independent on the tracer used and may therefore be added to any dynamic cardiac PET protocol. The aim of this study...... was to validate automated methods for extracting FSV directly from dynamic PET studies for two different tracers and to examine potential scanner hardware bias. Methods: 21 subjects underwent a dynamic 27 min 11C-acetate PET scan on a Siemens Biograph TruePoint 64 PET/CT scanner (scanner I). In addition, 8...... subjects underwent a dynamic 6 min 15O-water PET scan followed by a 27 min 11C-acetate PET scan on a GE Discovery ST PET/CT scanner (scanner II). The LV-aortic time-activity curve (TAC) was extracted automatically from dynamic PET data using cluster analysis. The first-pass peak was isolated by automatic...

Stimulation of NADH-dependent microsomal DNA strand cleavage by rifamycin SV.

Science.gov (United States)

Kukiełka, E; Cederbaum, A I

1995-04-15

Rifamycin SV is an antibiotic anti-bacterial agent used in the treatment of tuberculosis. This drug can autoxidize, especially in the presence of metals, and generate reactive oxygen species. A previous study indicated that rifamycin SV can increase NADH-dependent microsomal production of reactive oxygen species. The current study evaluated the ability of rifamycin SV to interact with iron and increase microsomal production of hydroxyl radical, as detected by conversion of supercoiled plasmid DNA into the relaxed open circular state. The plasmid used was pBluescript II KS(-), and the forms of DNA were separated by agarose-gel electrophoresis. Incubation of rat liver microsomes with plasmid plus NADH plus ferric-ATP caused DNA strand cleavage. The addition of rifamycin SV produced a time- and concentration-dependent increase in DNA-strand cleavage. No stimulation by rifamycin SV occurred in the absence of microsomes, NADH or ferric-ATP. Stimulation occurred with other ferric complexes besides ferric-ATP, e.g. ferric-histidine, ferric-citrate, ferric-EDTA, and ferric-(NH4)2SO4. Rifamycin SV did not significantly increase the high rates of DNA strand cleavage found with NADPH as the microsomal reductant. The stimulation of NADH-dependent microsomal DNA strand cleavage was completely blocked by catalase, superoxide dismutase, GSH and a variety of hydroxyl-radical-scavenging agents, but not by anti-oxidants that prevent microsomal lipid peroxidation. Redox cycling agents, such as menadione and paraquat, in contrast with rifamycin SV, stimulated the NADPH-dependent reaction; menadione and rifamycin SV were superior to paraquat in stimulating the NADH-dependent reaction. These results indicate that rifamycin SV can, in the presence of an iron catalyst, increase microsomal production of reactive oxygen species which can cause DNA-strand cleavage. In contrast with other redox cycling agents, the stimulation by rifamycin SV is more pronounced with NADH than with NADPH as the

Assessment of collateral status by dynamic ct angiography in acute mca stroke : Timing of acquisition and relationship with final infarct volume

NARCIS (Netherlands)

Van Den Wijngaard, I. R.; Holswilder, G.; Wermer, M. J H; Boiten, J.; Algra, A.; Dippel, D. W J; Dankbaar, J. W.; Velthuis, B. K.; Boers, A. M M; Majoie, C. B L M; Van Walderveen, M. A A

2016-01-01

BACKGROUND AND PURPOSE: Dynamic CTA is a promising technique for visualization of collateral filling in patients with acute ischemic stroke. Our aim was to describe collateral filling with dynamic CTA and assess the relationship with infarct volume at follow-up. MATERIALS AND METHODS: We selected

Assessment of collateral status by dynamic ct angiography in acute mca stroke: Timing of acquisition and relationship with final infarct volume

NARCIS (Netherlands)

I.R. Van Den Wijngaard (Ido R.); G. Holswilder (Ghislaine); M.J.H. Wermer (Marieke); J. Boiten (Jelis); A. Algra (Ale); D.W.J. Dippel (Diederik); J.W. Dankbaar (Jan); B.K. Velthuis (Birgitta); A.M.M. Boers (Anna); C.B. Majoie (Charles); M.A.A. van Walderveen (Marianne)

2016-01-01

textabstractBACKGROUND AND PURPOSE: Dynamic CTA is a promising technique for visualization of collateral filling in patients with acute ischemic stroke. Our aim was to describe collateral filling with dynamic CTA and assess the relationship with infarct volume at follow-up. MATERIALS AND METHODS: We

Possible Anandamide and Palmitoylethanolamide involvement in human stroke

Directory of Open Access Journals (Sweden)

Pizzolato Gilberto

2010-05-01

Full Text Available Abstract Background Endocannabinoids (eCBs are ubiquitous lipid mediators that act on specific (CB1, CB2 and non-specific (TRPV1, PPAR receptors. Despite many experimental animal studies proved eCB involvement in the pathogenesis of stroke, such evidence is still lacking in human patients. Our aim was to determine eCB peripheral levels in acute stroke patients and evaluate their relationship with clinical disability and stroke volume. Methods A cohort of ten patients with a first acute (within six hours since symptoms onset ischemic stroke and a group of eight age- and sex-matched normal subjects were included. Groups were also matched for metabolic profile. All subjects underwent a blood sample collection for anandamide (AEA, 2-arachidonoylglycerol (2-AG and palmitoylethanolamide (PEA measurement; blood sampling was repeated in patients on admission (T0, at 6 (T1 and 18 hours (T2 thereafter. Patients neurological impairment was assessed using NIHSS and Fugl-Meyer Scale arm subitem (FMSa; stroke volume was determined on 48 h follow-up brain CT scans. Blood samples were analyzed by liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry. Results 1T0 AEA levels were significantly higher in stroke patients compared to controls. 2A significant inverse correlation between T0 AEA levels and FMSa score was found. Moreover a positive correlation between T0 AEA levels and stroke volume were found in stroke patients. T0 PEA levels in stroke patients were not significantly different from the control group, but showed a significant correlation with the NIHSS scores. T0 2-AG levels were lower in stroke patients compared to controls, but such difference did not reach the significance threshold. Conclusions This is the first demonstration of elevated peripheral AEA levels in acute stroke patients. In agreement with previous murine studies, we found a significant relationship between AEA or PEA levels and neurological involvement, such

Right hemisphere grey matter structure and language outcomes in chronic left hemisphere stroke

Science.gov (United States)

Xing, Shihui; Lacey, Elizabeth H.; Skipper-Kallal, Laura M.; Jiang, Xiong; Harris-Love, Michelle L.; Zeng, Jinsheng

2016-01-01

The neural mechanisms underlying recovery of language after left hemisphere stroke remain elusive. Although older evidence suggested that right hemisphere language homologues compensate for damage in left hemisphere language areas, the current prevailing theory suggests that right hemisphere engagement is ineffective or even maladaptive. Using a novel combination of support vector regression-based lesion-symptom mapping and voxel-based morphometry, we aimed to determine whether local grey matter volume in the right hemisphere independently contributes to aphasia outcomes after chronic left hemisphere stroke. Thirty-two left hemisphere stroke survivors with aphasia underwent language assessment with the Western Aphasia Battery-Revised and tests of other cognitive domains. High-resolution T1-weighted images were obtained in aphasia patients and 30 demographically matched healthy controls. Support vector regression-based multivariate lesion-symptom mapping was used to identify critical language areas in the left hemisphere and then to quantify each stroke survivor’s lesion burden in these areas. After controlling for these direct effects of the stroke on language, voxel-based morphometry was then used to determine whether local grey matter volumes in the right hemisphere explained additional variance in language outcomes. In brain areas in which grey matter volumes related to language outcomes, we then compared grey matter volumes in patients and healthy controls to assess post-stroke plasticity. Lesion–symptom mapping showed that specific left hemisphere regions related to different language abilities. After controlling for lesion burden in these areas, lesion size, and demographic factors, grey matter volumes in parts of the right temporoparietal cortex positively related to spontaneous speech, naming, and repetition scores. Examining whether domain general cognitive functions might explain these relationships, partial correlations demonstrated that grey matter

Intraoperative stroke volume optimization using stroke volume, arterial pressure, and heart rate: closed-loop (learning intravenous resuscitator) versus anesthesiologists.

Science.gov (United States)

Rinehart, Joseph; Chung, Elena; Canales, Cecilia; Cannesson, Maxime

2012-10-01

The authors compared the performance of a group of anesthesia providers to closed-loop (Learning Intravenous Resuscitator [LIR]) management in a simulated hemorrhage scenario using cardiac output monitoring. A prospective cohort study. In silico simulation. University hospital anesthesiologists and the LIR closed-loop fluid administration system. Using a patient simulator, a 90-minute simulated hemorrhage protocol was run, which included a 1,200-mL blood loss over 30 minutes. Twenty practicing anesthesiology providers were asked to manage this scenario by providing fluids and vasopressor medication at their discretion. The simulation program was also run 20 times with the LIR closed-loop algorithm managing fluids and an additional 20 times with no intervention. Simulated patient weight, height, heart rate, mean arterial pressure, and cardiac output (CO) were similar at baseline. The mean stroke volume, the mean arterial pressure, CO, and the final CO were higher in the closed-loop group than in the practitioners group, and the coefficient of variance was lower. The closed-loop group received slightly more fluid (2.1 v 1.9 L, p closed-loop maintained more stable hemodynamics than the practitioners primarily because the fluid was given earlier in the protocol and CO optimized before the hemorrhage began, whereas practitioners tended to resuscitate well but only after significant hemodynamic change indicated the need. Overall, these data support the potential usefulness of this closed-loop algorithm in clinical settings in which dynamic predictors are not available or applicable. Published by Elsevier Inc.

pSv3neo transfection and radiosensitivity of human cancer cell lines

International Nuclear Information System (INIS)

Parris, C.N.; Masters, J.R.W.; Green, M.H.L.

1990-01-01

Immortalisation of human fibroblasts by transfection with a plasmid, pSV3neo, results in an increase in their radioresistance. The change in radiosensitivity may either be a consequence of transformation or due to expression of the SV40 T-antigen in pSV3neo. To investigate these two possibilities, we transfected pSV3neo into cells already transformed and immortalised. The radiosensitivies of three human bladder cancer cell lines were unaltered in clones expressing T-antigen, indicating that the changes observed in fibroblasts probably are a consequence of transformation, and not the presence of SV40 T-antigen. (author)

Ipsilateral hippocampal atrophy is associated with long-term memory dysfunction after ischemic stroke in young adults.

Science.gov (United States)

Schaapsmeerders, Pauline; van Uden, Inge W M; Tuladhar, Anil M; Maaijwee, Noortje A M; van Dijk, Ewoud J; Rutten-Jacobs, Loes C A; Arntz, Renate M; Schoonderwaldt, Hennie C; Dorresteijn, Lucille D A; de Leeuw, Frank-Erik; Kessels, Roy P C

2015-07-01

Memory impairment after stroke in young adults is poorly understood. In elderly stroke survivors memory impairments and the concomitant loss of hippocampal volume are usually explained by coexisting neurodegenerative disease (e.g., amyloid pathology) in interaction with stroke. However, neurodegenerative disease, such as amyloid pathology, is generally absent at young age. Accumulating evidence suggests that infarction itself may cause secondary neurodegeneration in remote areas. Therefore, we investigated the relation between long-term memory performance and hippocampal volume in young patients with first-ever ischemic stroke. We studied all consecutive first-ever ischemic stroke patients, aged 18-50 years, admitted to our academic hospital center between 1980 and 2010. Episodic memory of 173 patients was assessed using the Rey Auditory Verbal Learning Test and the Rey Complex Figure and compared with 87 stroke-free controls. Hippocampal volume was determined using FSL-FIRST, with manual correction. On average 10 years after stroke, patients had smaller ipsilateral hippocampal volumes compared with controls after left-hemispheric stroke (5.4%) and right-hemispheric stroke (7.7%), with most apparent memory dysfunctioning after left-hemispheric stroke. A larger hemispheric stroke was associated with a smaller ipsilateral hippocampal volume (b=-0.003, Pstroke (b=-0.028 ml, P=0.002) and right-hemispheric stroke (b=-0.015 ml, P=0.03). Our results suggest that infarction is associated with remote injury to the hippocampus, which may lower or expedite the threshold for cognitive impairment or even dementia later in life. © 2015 Wiley Periodicals, Inc.

Right hemisphere grey matter structure and language outcomes in chronic left hemisphere stroke.

Science.gov (United States)

Xing, Shihui; Lacey, Elizabeth H; Skipper-Kallal, Laura M; Jiang, Xiong; Harris-Love, Michelle L; Zeng, Jinsheng; Turkeltaub, Peter E

2016-01-01

The neural mechanisms underlying recovery of language after left hemisphere stroke remain elusive. Although older evidence suggested that right hemisphere language homologues compensate for damage in left hemisphere language areas, the current prevailing theory suggests that right hemisphere engagement is ineffective or even maladaptive. Using a novel combination of support vector regression-based lesion-symptom mapping and voxel-based morphometry, we aimed to determine whether local grey matter volume in the right hemisphere independently contributes to aphasia outcomes after chronic left hemisphere stroke. Thirty-two left hemisphere stroke survivors with aphasia underwent language assessment with the Western Aphasia Battery-Revised and tests of other cognitive domains. High-resolution T1-weighted images were obtained in aphasia patients and 30 demographically matched healthy controls. Support vector regression-based multivariate lesion-symptom mapping was used to identify critical language areas in the left hemisphere and then to quantify each stroke survivor's lesion burden in these areas. After controlling for these direct effects of the stroke on language, voxel-based morphometry was then used to determine whether local grey matter volumes in the right hemisphere explained additional variance in language outcomes. In brain areas in which grey matter volumes related to language outcomes, we then compared grey matter volumes in patients and healthy controls to assess post-stroke plasticity. Lesion-symptom mapping showed that specific left hemisphere regions related to different language abilities. After controlling for lesion burden in these areas, lesion size, and demographic factors, grey matter volumes in parts of the right temporoparietal cortex positively related to spontaneous speech, naming, and repetition scores. Examining whether domain general cognitive functions might explain these relationships, partial correlations demonstrated that grey matter

Specifications for Testing Procedures at Svåheia

DEFF Research Database (Denmark)

Margheritini, Lucia; Kofoed, Jens Peter

This report is realized in order to define testing procedures of the SSG pilot in Svåheia location. This will be done by listing all the relevant parameters related to the structure performance.......This report is realized in order to define testing procedures of the SSG pilot in Svåheia location. This will be done by listing all the relevant parameters related to the structure performance....

Accuracy of right and left ventricular functional assessment by short-axis vs axial cine steady-state free-precession magnetic resonance imaging: intrapatient correlation with main pulmonary artery and ascending aorta phase-contrast flow measurements.

Science.gov (United States)

James, Susan H; Wald, Rachel; Wintersperger, Bernd J; Jimenez-Juan, Laura; Deva, Djeven; Crean, Andrew M; Nguyen, Elsie; Paul, Narinder S; Ley, Sebastian

2013-08-01

The left ventricle (LV) is routinely assessed with cardiac magnetic resonance imaging (MRI) by using short-axis orientation; it remains unclear whether the right ventricle (RV) can also be adequately assessed in this orientation or whether dedicated axial orientation is required. We used phase-contrast (PC) flow measurements in the main pulmonary artery (MPA) and the ascending aorta (Aorta) as nonvolumetric standard of reference and compared RV and LV volumes in short-axis and axial orientations. A retrospective analysis identified 30 patients with cardiac MRI data sets. Patients underwent MRI (1.5 T or 3 T), with retrospectively gated cine steady-state free-precession in axial and short-axis orientations. PC flow analyses of MPA and Aorta were used as the reference measure of RV and LV output. There was a high linear correlation between MPA-PC flow and RV-stroke volume (SV) short axis (r = 0.9) and RV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 1.4 mL for RV axial and -2.3 mL for RV-short-axis vs MPA-PC flow. There was a high linear correlation between Aorta-PC flow and LV-SV short-axis (r = 0.9) and LV-SV axial (r = 0.9). Bland-Altman analysis revealed a mean offset of 4.8 m for LV short axis and 7.0 mL for LV axial vs Aorta-PC flow. There was no significant difference (P = .6) between short-axis-LV SV and short-axis-RV SV. No significant impact of the slice acquisition orientation for determination of RV and LV stroke volumes was found. Therefore, cardiac magnetic resonance workflow does not need to be extended by an axial data set for patients without complex cardiac disease for assessment of biventricular function and volumes. Copyright © 2013 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

Goal-directed fluid optimization based on stroke volume variation and cardiac index during one-lung ventilation in patients undergoing thoracoscopy lobectomy operations: a pilot study

Directory of Open Access Journals (Sweden)

Jian Zhang

2013-07-01

Full Text Available OBJECTIVES: This pilot study was designed to utilize stroke volume variation and cardiac index to ensure fluid optimization during one-lung ventilation in patients undergoing thoracoscopic lobectomies. METHODS: Eighty patients undergoing thoracoscopic lobectomy were randomized into either a goal-directed therapy group or a control group. In the goal-directed therapy group, the stroke volume variation was controlled at 10%±1%, and the cardiac index was controlled at a minimum of 2.5 L.min-1.m-2. In the control group, the MAP was maintained at between 65 mm Hg and 90 mm Hg, heart rate was maintained at between 60 BPM and 100 BPM, and urinary output was greater than 0.5 mL/kg-1/h-1. The hemodynamic variables, arterial blood gas analyses, total administered fluid volume and side effects were recorded. RESULTS: The PaO2/FiO2-ratio before the end of one-lung ventilation in the goal-directed therapy group was significantly higher than that of the control group, but there were no differences between the goal-directed therapy group and the control group for the PaO2/FiO2-ratio or other arterial blood gas analysis indices prior to anesthesia. The extubation time was significantly earlier in the goal-directed therapy group, but there was no difference in the length of hospital stay. Patients in the control group had greater urine volumes, and they were given greater colloid and overall fluid volumes. Nausea and vomiting were significantly reduced in the goal-directed therapy group. CONCLUSION: The results of this study demonstrated that an optimization protocol, based on stroke volume variation and cardiac index obtained with a FloTrac/Vigileo device, increased the PaO2/FiO2-ratio and reduced the overall fluid volume, intubation time and postoperative complications (nausea and vomiting in thoracic surgery patients requiring one-lung ventilation.

The longitudinal effect of ejaculation on seminal vesicle fluid volume and whole-prostate ADC as measured on prostate MRI

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Barrett, Tristan; Gallagher, Ferdia A. [Addenbrooke' s Hospital and University of Cambridge, Department of Radiology, Cambridge (United Kingdom); Addenbrooke' s Hospital and University of Cambridge, CamPARI Clinic, Cambridge (United Kingdom); Tanner, James; Gill, Andrew B.; Slough, Rhys A. [Addenbrooke' s Hospital and University of Cambridge, Department of Radiology, Cambridge (United Kingdom); Wason, James [University of Cambridge, MRC Biostatistics Unit, Cambridge (United Kingdom)

2017-12-15

To prospectively investigate the longitudinal effect of ejaculatory abstinence on MRI-measured seminal vesicle (SV) volume and whole-prostate ADC over consecutive days. 15 healthy male volunteers (mean 35.9 years, range 27-53) underwent 3-T MRI at baseline and 1, 2 and 3 days post-ejaculation. Prostate and SV volumes were derived by volume segmentation and whole-gland apparent diffusion coefficient (ADC) values calculated. A mixed-effects linear regression compared ADC values and prostate/seminal vesicle volumes in each volunteer between studies in a pairwise manner. All subjects completed the four MRIs. Mean prostate volume was 22.45 cm{sup 3} (range 13.04-31.21 cm{sup 3}), with no change between the four studies (p = 0.89-0.99). 13/15 subjects showed SV volume reduction from baseline to day 1, with group-mean decreasing from 6.45 to 4.80 cm{sup 3} (-25.6%, p < 0.001), and a significant reduction from baseline to day 2 (-18.1%, p = 0.002). There was a significant volume increase from both day 1 (+21.3%, p = 0.006) and day 2 (+10.2%, p = 0.022) to day 3 post-ejaculation. There was a significant reduction in ADC from 1.105 at baseline to 1.056 x 10{sup -3} mm{sup 2}/s at day 1 (mean -4.3%, p = 0.009). The longitudinal effect of ejaculation on SV volume was demonstrated. Significant reductions in SV volume and whole-gland ADC were observed post-ejaculation, supporting a 3-day period of abstinence before prostate MRI. (orig.)

Post-stroke dementia: the contribution of thalamus and basal ganglia changes.

Science.gov (United States)

Lopes, Marcos Antonio; Firbank, Michael J; Widdrington, Michelle; Blamire, Andrew M; Kalaria, Raj N; O'Brien, John T

2012-04-01

The neurobiological basis of increased risk of dementia in stroke patients is unclear, though there are several related pathological changes, including white matter hyperintensities (WMH), and medial temporal atrophy. Subcortical gray matter structures have also been implicated in dementia resulting from vascular pathology, particularly vascular dementia. This study aimed to investigate the contribution of changes in subcortical gray matter structures to post-stroke dementia (PSD). T1- and T2-weighted images and T2-weighted fluid-attenuated inversion recovery (FLAIR) images were obtained on a 3-Tesla magnetic resonance (MR) system, in four groups aged over 75 years: post-stroke with dementia (PSD; 8), post-stroke no dementia (PSnoD; 33), Alzheimer's disease (AD; 26) and controls (30). Automated software was used to measure the volume of thalamus, putamen, caudate nucleus, and hippocampus as well as total WMH volume. The number of subcortical lacunes was also counted. The number of caudate lacunes was higher in the PSnoD group, compared with AD (p = 0.029) and controls (p = 0.019). The putamen volume was smaller in the stroke and AD groups, when compared with controls. In the whole stroke group, putamen lacunes were correlated with impairment in memory (Rey test; ρ = -0.365; p = 0.031), while WMH and hippocampal volume both correlated with global dysfunction. Our findings implicate a variety of neurobiological substrates of dementia, such as small vessel disease and Alzheimer pathology, which develop after stroke in an old older population, with a contribution from subcortical brain structures.

A novel splice variant of supervillin, SV5, promotes carcinoma cell proliferation and cell migration

International Nuclear Information System (INIS)

Chen, Xueran; Yang, Haoran; Zhang, Shangrong; Wang, Zhen; Ye, Fang; Liang, Chaozhao; Wang, Hongzhi; Fang, Zhiyou

2017-01-01

Supervillin is an actin-associated protein that regulates actin dynamics by interacting with Myosin II, F-actin, and Cortactin to promote cell contractility and cell motility. Two splicing variants of human Supervillin (SV1 and SV4) have been reported in non-muscle cells; SV1 lacks 3 exons present in the larger isoform SV4. SV2, also called archvillin, is present in striated muscle; SV3, also called smooth muscle archvillin or SmAV, was cloned from smooth muscle. In the present study, we identify a novel splicing variant of Supervillin (SV5). SV5 contains a new splicing pattern. In the mouse tissues and cell lines examined, SV5 was predominantly expressed in skeletal and cardiac muscles and in proliferating cells, but was virtually undetectable in most normal tissues. Using RNAi and rescue experiments, we show here that SV5 displays altered functional properties in cancer cells, and regulates cell proliferation and cell migration.

Which goal for fluid therapy during colorectal surgery is followed by the best outcome

DEFF Research Database (Denmark)

Brandstrup, B; Svendsen, P E; Rasmussen, M

2012-01-01

/st> We aimed to investigate whether fluid therapy with a goal of near-maximal stroke volume (SV) guided by oesophageal Doppler (ED) monitoring result in a better outcome than that with a goal of maintaining bodyweight (BW) and zero fluid balance in patients undergoing colorectal surgery....

Stimulation of NADH-dependent microsomal DNA strand cleavage by rifamycin SV.

OpenAIRE

Kukiełka, E; Cederbaum, A I

1995-01-01

Rifamycin SV is an antibiotic anti-bacterial agent used in the treatment of tuberculosis. This drug can autoxidize, especially in the presence of metals, and generate reactive oxygen species. A previous study indicated that rifamycin SV can increase NADH-dependent microsomal production of reactive oxygen species. The current study evaluated the ability of rifamycin SV to interact with iron and increase microsomal production of hydroxyl radical, as detected by conversion of supercoiled plasmid...

Effect of volume loading on the Frank-Starling relation during reductions in central blood volume in heat-stressed humans

DEFF Research Database (Denmark)

Bundgaard-Nielsen, Morten; Wilson, T E; Seifert, Thomas

2010-01-01

-body heating after intravascular volume expansion. Volume expansion was accomplished by administration of a combination of a synthetic colloid (HES 130/0.4, Voluven) and saline. Before LBNP, SV was not affected by heating (122 +/- 30 ml; mean +/- s.d.) compared to normothermia (110 +/- 20 ml; P = 0...

Association of serial biochemical markers with acute ischemic stroke: the National Institute of Neurological Disorders and Stroke recombinant tissue plasminogen activator Stroke Study.

Science.gov (United States)

Jauch, Edward C; Lindsell, Christopher; Broderick, Joseph; Fagan, Susan C; Tilley, Barbara C; Levine, Steven R

2006-10-01

Biochemical markers of acute neuronal injury may aid in the diagnosis and management of acute ischemic stroke. Serum samples from the National Institute for Neurological Disorders and Stroke (NINDS) recombinant tissue plasminogen activator Stroke Study were analyzed for the presence of 4 biochemical markers of neuronal, glial, and endothelial cell injury. These biochemical markers, myelin basic protein (MBP), neuron-specific enolase (NSE), S100beta, and soluble thrombomodulin, were studied for an association with initial stroke severity, infarct volume, and functional outcome. In the original NINDS study, serum samples were drawn from all patients on presentation to the Emergency Department and at approximately 2 and 24 hours after initiation of study therapy. In this analysis, stored serum samples were available for 359 patients; 107 patients had samples for all 3 time points. Serum marker concentrations were measured by ELISA techniques. We examined the relation between serum concentrations of each marker and the degree of baseline neurological deficit, functional outcome, and infarct size on computed tomography at 24 hours and the effect of fibrinolytic therapy. Higher 24-hour peak concentrations of MBP, NSE, and S100beta were associated with higher National Institutes of Health Stroke Scale baseline scores (r=0.186, P<0.0001; r=0.117, P=0.032; and r=0.263, P<0.0001, respectively). Higher peak concentrations of MBP and S100beta (r=0.209, P<0.0001; r=0.239, P<0.0001) were associated with larger computed tomography lesion volumes. Patients with favorable outcomes had smaller changes in MBP and S100beta (P<0.05) concentrations in the first 24 hours. Soluble thrombomodulin was not associated with any severity or outcome measure. This study corroborates previous work demonstrating correlations of MBP, NSE, and S100beta with clinical and radiographic features in acute stroke. Despite significantly better outcomes in the tissue plasminogen activator-treated group, we

Development of direct reading dosimeters for the dose 0-3 mSv and 0-5 mSv ranges for personnel monitoring

International Nuclear Information System (INIS)

Gaikwad, P.V.; Shirkar, Y.B.; Patil, A.S.; Madgaonkar, P.P.; Kale, K.L.; Guhagarkar, H.V.; Gandhi, D.P.; Gupta, S.K.; Kothiyal, G.P.; Sahni, V.C.

1998-01-01

Direct reading dosimeters (DRDs) are widely used to measure cumulative dose received by personnel working at nuclear reactor sites or in other environment having x- and gamma rays. A DRD operates on the principle of gold leaf electroscope, and is a small, rugged, hermetically sealed, self reading type device easily carried by an individual in his pocket. The development of dosimeters suitable for the dose ranges 0-3 mSv and 0-5 mSv is reported

Improved approach to quantitative cardiac volumetrics using automatic thresholding and manual trimming: a cardiovascular MRI study.

Science.gov (United States)

Rayarao, Geetha; Biederman, Robert W W; Williams, Ronald B; Yamrozik, June A; Lombardi, Richard; Doyle, Mark

2018-01-01

To establish the clinical validity and accuracy of automatic thresholding and manual trimming (ATMT) by comparing the method with the conventional contouring method for in vivo cardiac volume measurements. CMR was performed on 40 subjects (30 patients and 10 controls) using steady-state free precession cine sequences with slices oriented in the short-axis and acquired contiguously from base to apex. Left ventricular (LV) volumes, end-diastolic volume, end-systolic volume, and stroke volume (SV) were obtained with ATMT and with the conventional contouring method. Additionally, SV was measured independently using CMR phase velocity mapping (PVM) of the aorta for validation. Three methods of calculating SV were compared by applying Bland-Altman analysis. The Bland-Altman standard deviation of variation (SD) and offset bias for LV SV for the three sets of data were: ATMT-PVM (7.65, [Formula: see text]), ATMT-contours (7.85, [Formula: see text]), and contour-PVM (11.01, 4.97), respectively. Equating the observed range to the error contribution of each approach, the error magnitude of ATMT:PVM:contours was in the ratio 1:2.4:2.5. Use of ATMT for measuring ventricular volumes accommodates trabeculae and papillary structures more intuitively than contemporary contouring methods. This results in lower variation when analyzing cardiac structure and function and consequently improved accuracy in assessing chamber volumes.

Test of models for replication of SV40 DNA following UV irradiation

International Nuclear Information System (INIS)

Barnett, S.W.

1983-01-01

The replication of SV40 DNA immediately after irradiation of infected monkey cells has been examined. SV40 DNA synthesis is inhibited in a UV fluence-dependent fashion, and the synthesis of completely replicated (Form I) SV40 molecules is more severely inhibited than is total SV40 DNA synthesis. Two models for DNA replication-inhibition have been tested. Experimental results have been compared to those predicted by mathematical models derived to describe two possible molecular mechanisms of replication inhibition. No effect of UV irradiation on the uptake and phosphorylation of 3 H-thymidine nor on the size of the intracellular deoxythymidine triphosphate pool of SV40-infected cells have been observed, validating the use of 3 H-thymidine incorporation as a measure of DNA synthesis in this system. In vitro studies have been performed to further investigate the mechanism of dimer-specific inhibition of completion of SV40 DNA synthesis observed in in vivo. The results of these studies are consistent with a mechanism of discontinuous synthesis past dimer sites, but it is equally possible that the mechanism of DNA replication of UV-damaged DNA in the in vitro system is different from that which occurs in vivo

Better Diffusion Segmentation in Acute Ischemic Stroke Through Automatic Tree Learning Anomaly Segmentation

Directory of Open Access Journals (Sweden)

Jens K. Boldsen

2018-04-01

Full Text Available Stroke is the second most common cause of death worldwide, responsible for 6.24 million deaths in 2015 (about 11% of all deaths. Three out of four stroke survivors suffer long term disability, as many cannot return to their prior employment or live independently. Eighty-seven percent of strokes are ischemic. As an increasing volume of ischemic brain tissue proceeds to permanent infarction in the hours following the onset, immediate treatment is pivotal to increase the likelihood of good clinical outcome for the patient. Triaging stroke patients for active therapy requires assessment of the volume of salvageable and irreversible damaged tissue, respectively. With Magnetic Resonance Imaging (MRI, diffusion-weighted imaging is commonly used to assess the extent of permanently damaged tissue, the core lesion. To speed up and standardize decision-making in acute stroke management we present a fully automated algorithm, ATLAS, for delineating the core lesion. We compare performance to widely used threshold based methodology, as well as a recently proposed state-of-the-art algorithm: COMBAT Stroke. ATLAS is a machine learning algorithm trained to match the lesion delineation by human experts. The algorithm utilizes decision trees along with spatial pre- and post-regularization to outline the lesion. As input data the algorithm takes images from 108 patients with acute anterior circulation stroke from the I-Know multicenter study. We divided the data into training and test data using leave-one-out cross validation to assess performance in independent patients. Performance was quantified by the Dice index. The median Dice coefficient of ATLAS algorithm was 0.6122, which was significantly higher than COMBAT Stroke, with a median Dice coefficient of 0.5636 (p < 0.0001 and the best possible performing methods based on thresholding of the diffusion weighted images (median Dice coefficient: 0.3951 or the apparent diffusion coefficient (median Dice coefficeint

SV2: accurate structural variation genotyping and de novo mutation detection from whole genomes.

Science.gov (United States)

Antaki, Danny; Brandler, William M; Sebat, Jonathan

2018-05-15

Structural variation (SV) detection from short-read whole genome sequencing is error prone, presenting significant challenges for population or family-based studies of disease. Here, we describe SV2, a machine-learning algorithm for genotyping deletions and duplications from paired-end sequencing data. SV2 can rapidly integrate variant calls from multiple structural variant discovery algorithms into a unified call set with high genotyping accuracy and capability to detect de novo mutations. SV2 is freely available on GitHub (https://github.com/dantaki/SV2). jsebat@ucsd.edu. Supplementary data are available at Bioinformatics online.

A study on regional cerebral circulation in stroke patients with aphasia

International Nuclear Information System (INIS)

Kudo, Ryozo

1985-01-01

To study the pathophysiology of aphasia due to cerebral stroke, regional cerebral blood flow (rCBF) was measured by the 133 Xe clearance method and the volume of low density area (LDA) was estimated on the basis of computerized tomography in 43 thrombotic (24 aphasia and 19 non-aphasia), 30 hemorrhagic (16 aphasia and 14 non-aphasia) and 6 non-stroke cases. 1) In the healthy hemisphere, rCBF showed no significant difference between aphasia and non-aphasia in both thrombotic and hemorrhagic cases. In the affected hemisphere, thrombotic cases showed significantly decreased rCBF in aphasic cases as compared to non-aphasic, however, hemorrhagic cases revealed no difference. 2) LDA volume showed no significant difference between aphasia and non-aphasia in cerebral thrombosis, however, LDA volume in non-aphasia was smaller than that in aphasia in cerebral hemorrage. 3) Significant differences in the pathophysiology of aphasia due to cerebral stroke were recognized between cerebral thrombosis and cerebral hemorrhage. Such differences should be taken into consideration in the management and treatment of aphasia caused by cerebral stroke. (author)

The magnitude and course of exercise-induced stroke volume changes determine the exercise tolerance in heart transplant recipients with heart failure and normal ejection fraction

Czech Academy of Sciences Publication Activity Database

Meluzín, J.; Hude, P.; Leinveber, P.; Jurák, Pavel; Soukup, L.; Viščor, Ivo; Špinarová, L.; Štěpánová, R.; Podroužková, H.; Vondra, Vlastimil; Langer, P.; Němec, P.

2014-01-01

Roč. 20, č. 1 (2014), s. 674-687 ISSN 1205-6626 R&D Projects: GA MŠk(CZ) LO1212 Keywords : heart failure * stroke volume index * exercise tolerance * bioimpedance Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 0.758, year: 2013

Solid state fermentation and production of rifamycin SV using Amycolatopsis mediterranei.

Science.gov (United States)

Nagavalli, M; Ponamgi, S P D; Girijashankar, V; Venkateswar Rao, L

2015-01-01

Production of Rifamycin SV from cheaper agro-industrial by-products using mutant strain of Amycolatopsis mediterranei OVA5-E7 in solid state fermentation (SSF) was optimized. Among the agro-based substrates used, ragi bran was found suitable for maximizing the yield of Rifamycin SV (1310 mg 100 g(-1) ds). The yield can be further enhanced to 19·7 g Kg(-1) of dry substrate by supplementing the substrate with deoiled cotton cake (10% w/w) using optimized fermentation parameters such as maintaining 80% moisture, pH 7·0, 30°C incubation temperature, inoculum 25% v/w and carrying the solid state fermenting for 9 days. Manipulating these seven specifications, the end product yield achieved in our experimentation was 20 g of Rifamycin SV Kg(-1) ds. Eventually, an overall 5-fold improvement in Rifamycin SV production was achieved. Antibiotics such as rifamycin are broad-spectrum antimicrobial drugs used in large-scale worldwide as human medicine towards controlling diseases. Amycolatopsis mediterranei strain which produces this antibiotic was earlier used in submerged fermentation yielded lower amounts of rifamycin. By employing cheaper agro-industrial by-products, we produced upto 20 g rifamycin SV per Kg dry substrate used under optimized solid state fermentation conditions. Keeping in view, the role of rifamycin in meeting the medical demands of world's increasing population; we successfully used an improved strain on cheaper substrates with optimized fermentation parameters and achieved a 5-fold improvement in rifamycin SV production. © 2014 The Society for Applied Microbiology.

Effect of fluid loading on left ventricular volume and stroke volume variability in patients with end-stage renal disease: a pilot study

Science.gov (United States)

Kanda, Hirotsugu; Hirasaki, Yuji; Iida, Takafumi; Kanao-Kanda, Megumi; Toyama, Yuki; Kunisawa, Takayuki; Iwasaki, Hiroshi

2015-01-01

Purpose The aim of this study was to investigate fluid loading-induced changes in left ventricular end-diastolic volume (LVEDV) and stroke volume variability (SVV) in patients with end-stage renal disease (ESRD) using real-time three-dimensional transesophageal echocardiography and the Vigileo-FloTrac system. Patients and methods After obtaining ethics committee approval and informed consent, 28 patients undergoing peripheral vascular procedures were studied. Fourteen patients with ESRD on hemodialysis (HD) were assigned to the HD group and 14 patients without ESRD were assigned to the control group. Institutional standardized general anesthesia was provided in both groups. SVV was measured using the Vigileo-FloTrac system. Simultaneously, a full-volume three-dimensional transesophageal echocardiography dataset was acquired to measure LVEDV, left ventricular end-systolic volume, and left ventricular ejection fraction. Measurements were obtained before and after loading 500 mL hydroxyethyl starch over 30 minutes in both groups. Results In the control group, intravenous colloid infusion was associated with a significant decrease in SVV (13.8%±2.6% to 6.5%±2.6%, P<0.001) and a significant increase in LVEDV (83.6±23.4 mL to 96.1±28.8 mL, P<0.001). While SVV significantly decreased after infusion in the HD group (16.2%±6.0% to 6.2%±2.8%, P<0.001), there was no significant change in LVEDV. Conclusion Our preliminary data suggest that fluid responsiveness can be assessed not by LVEDV but also by SVV due to underlying cardiovascular pathophysiology in patients with ESRD. PMID:26527879

Perfusion differences on SPECT and PWI in patients with acute ischemic stroke

International Nuclear Information System (INIS)

Nuutinen, Juho; Liu, Yawu; Laakso, Mikko P.; Karonen, Jari O.; Vanninen, Esko J.; Kuikka, Jyrki T.; Aronen, Hannu J.; Vanninen, Ritva L.

2009-01-01

The purposes of the present study were to compare the flow defect volumes on perfusion-weighted magnetic resonance imaging (PWI) and 99m Tc-labeled ethylcysteinate dimer ( 99m Tc-ECD) single photon emission computed tomography (SPECT) at acute and subacute stages of ischemic stroke and to analyze the relationship between the detected flow defects on the two methods and neurological status and clinical outcomes. Perfusion defects on PWI and SPECT were measured within 48 h and on day 8 of the onset of stroke from 22 patients with their first-ever acute supratentorial ischemic stroke. The primary neurological status was evaluated prior to the imaging. Clinical outcome was assessed at 3 months after the onset of the stroke. The volumes of cerebral blood flow (CBF) defects did not differ between SPECT and PWI within the 48-h examinations. However, the volume of CBF defect was significantly larger on SPECT than on PWI on day 8 (p = 0.03). Within the 48-h examinations, the CBF defect volumes on SPECT and PWI were comparably related to the neurological status. On day 8, the CBF defect volume on SPECT showed higher correlation to the neurological status and more precisely predicted the clinical outcomes at 3 months than PWI. 99m TC-ECD-SPECT and PWI both have ability to detect cerebral hypoperfusion in patients with ischemic stroke but with some differences. The value of SPECT is more accurate in terms of the delayed outcome, such as prognosis and rehabilitation planning. (orig.)

Perfusion differences on SPECT and PWI in patients with acute ischemic stroke

Energy Technology Data Exchange (ETDEWEB)

Nuutinen, Juho [Kuopio University Hospital, University of Kuopio, Department of Neurology, Kuopio (Finland); Liu, Yawu; Laakso, Mikko P. [Kuopio University Hospital, University of Kuopio, Department of Neurology, Kuopio (Finland); Kuopio University Hospital, University of Kuopio, Department of Clinical Radiology, P. O. Box 1777, Kuopio (Finland); Karonen, Jari O. [Mikkeli Central Hospital, Department of Radiology, Mikkeli (Finland); Vanninen, Esko J. [Kuopio University Hospital, University of Kuopio, Department of Clinical Physiology and Nuclear Medicine, Kuopio (Finland); Kuikka, Jyrki T. [Kuopio University Hospital, University of Kuopio, Department of Clinical Physiology and Nuclear Medicine, Kuopio (Finland); Niuvanniemi Hospital, Kuopio (Finland); Aronen, Hannu J. [University of Turku, Department of Radiology, Turku (Finland); Vanninen, Ritva L. [Kuopio University Hospital, University of Kuopio, Department of Clinical Radiology, P. O. Box 1777, Kuopio (Finland)

2009-10-15

The purposes of the present study were to compare the flow defect volumes on perfusion-weighted magnetic resonance imaging (PWI) and {sup 99m}Tc-labeled ethylcysteinate dimer ({sup 99m}Tc-ECD) single photon emission computed tomography (SPECT) at acute and subacute stages of ischemic stroke and to analyze the relationship between the detected flow defects on the two methods and neurological status and clinical outcomes. Perfusion defects on PWI and SPECT were measured within 48 h and on day 8 of the onset of stroke from 22 patients with their first-ever acute supratentorial ischemic stroke. The primary neurological status was evaluated prior to the imaging. Clinical outcome was assessed at 3 months after the onset of the stroke. The volumes of cerebral blood flow (CBF) defects did not differ between SPECT and PWI within the 48-h examinations. However, the volume of CBF defect was significantly larger on SPECT than on PWI on day 8 (p = 0.03). Within the 48-h examinations, the CBF defect volumes on SPECT and PWI were comparably related to the neurological status. On day 8, the CBF defect volume on SPECT showed higher correlation to the neurological status and more precisely predicted the clinical outcomes at 3 months than PWI. {sup 99m}TC-ECD-SPECT and PWI both have ability to detect cerebral hypoperfusion in patients with ischemic stroke but with some differences. The value of SPECT is more accurate in terms of the delayed outcome, such as prognosis and rehabilitation planning. (orig.)

Calculation of left ventricular volumes and ejection fraction from dynamic cardiac-gated 15O-water PET/CT: 5D-PET.

Science.gov (United States)

Nordström, Jonny; Kero, Tanja; Harms, Hendrik Johannes; Widström, Charles; Flachskampf, Frank A; Sörensen, Jens; Lubberink, Mark

2017-11-14

Quantitative measurement of myocardial blood flow (MBF) is of increasing interest in the clinical assessment of patients with suspected coronary artery disease (CAD). 15 O-water positron emission tomography (PET) is considered the gold standard for non-invasive MBF measurements. However, calculation of left ventricular (LV) volumes and ejection fraction (EF) is not possible from standard 15 O-water uptake images. The purpose of the present work was to investigate the possibility of calculating LV volumes and LVEF from cardiac-gated parametric blood volume (V B ) 15 O-water images and from first pass (FP) images. Sixteen patients with mitral or aortic regurgitation underwent an eight-gate dynamic cardiac-gated 15 O-water PET/CT scan and cardiac MRI. V B and FP images were generated for each gate. Calculations of end-systolic volume (ESV), end-diastolic volume (EDV), stroke volume (SV) and LVEF were performed with automatic segmentation of V B and FP images, using commercially available software. LV volumes and LVEF were calculated with surface-, count-, and volume-based methods, and the results were compared with gold standard MRI. Using V B images, high correlations between PET and MRI ESV (r = 0.89, p  0.86, p dynamic 15 O-water PET is feasible and shows good correlation with MRI. However, the analysis method is laborious, and future work is needed for more automation to make the method more easily applicable in a clinical setting.

Venous responses during exercise in rainbow trout, Oncorhynchus mykiss : [alpha]-adrenergic control and the antihypotensive function of the renin-angiotensin system

DEFF Research Database (Denmark)

Sandblom, E.; Axelsson, M.; McKenzie, David

2006-01-01

) was investigated during exercise after [alpha]-adrenoceptor blockade. Fish were subjected to a 20-min exercise challenge at 0.66 body lengths s-1 (BL s-1) while Pven, dorsal aortic blood pressure (Pda) and relative cardiac output (Q) was recorded continuously. Heart rate (fH), cardiac stroke volume (SV) and total...

Automatic extraction of forward stroke volume using dynamic 11C-acetate PET/CT

DEFF Research Database (Denmark)

Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik

Objectives: Dynamic PET with 11C-acetate can be used to quantify myocardial blood flow and oxidative metabolism, the latter of which is used to calculate myocardial external efficiency (MEE). Calculation of MEE requires forward stroke volume (FSV) data. FSV is affected by cardiac loading conditions......, potentially introducing bias if measured with a separate modality. The aim of this study was to develop and validate methods for automatically extracting FSV directly from the dynamic PET used for measuring oxidative metabolism. Methods: 16 subjects underwent a dynamic 27 min PET scan on a Siemens Biograph...... TruePoint 64 PET/CT scanner after bolus injection of 399±27 MBq of 11C-acetate. The LV-aortic time-activity curve (TAC) was extracted automatically from dynamic PET data using cluster analysis. The first-pass peak was derived by automatic extrapolation of the down-slope of the TAC. FSV...

Ischemic Stroke Profile, Risk Factors, and Outcomes in India: The Indo-US Collaborative Stroke Project.

Science.gov (United States)

Sylaja, P N; Pandian, Jeyaraj Durai; Kaul, Subhash; Srivastava, M V Padma; Khurana, Dheeraj; Schwamm, Lee H; Kesav, Praveen; Arora, Deepti; Pannu, Aman; Thankachan, Tijy K; Singhal, Aneesh B

2018-01-01

The Indo-US Collaborative Stroke Project was designed to characterize ischemic stroke across 5 high-volume academic tertiary hospitals in India. From January 2012 to August 2014, research coordinators and physician coinvestigators prospectively collected data on 2066 patients with ischemic stroke admitted <2 weeks after onset. Investigator training and supervision and data monitoring were conducted by the US site (Massachusetts General Hospital, Boston). The mean age was 58.3±14.7 years, 67.2% men. The median admission National Institutes of Health Stroke Scale score was 10 (interquartile range, 5-15) and 24.5% had National Institutes of Health Stroke Scale ≥16. Hypertension (60.8%), diabetes mellitus (35.7%), and tobacco use (32.2%, including bidi/smokeless tobacco) were common risk factors. Only 4% had atrial fibrillation. All patients underwent computed tomography or magnetic resonance imaging; 81% had cerebrovascular imaging. Stroke etiologic subtypes were large artery (29.9%), cardiac (24.9%), small artery (14.2%), other definite (3.4%), and undetermined (27.6%, including 6.7% with incomplete evaluation). Intravenous or intra-arterial thrombolysis was administered in 13%. In-hospital mortality was 7.9%, and 48% achieved modified Rankin Scale score 0 to 2 at 90 days. On multivariate analysis, diabetes mellitus predicted poor 3-month outcome and younger age, lower admission National Institutes of Health Stroke Scale and small-artery etiology predicted excellent 3-month outcome. These comprehensive and novel clinical imaging data will prove useful in refining stroke guidelines and advancing stroke care in India. © 2017 American Heart Association, Inc.

Short and long-term effects of irbesartan on intradialytic central haemodynamics: A randomised double-blind placebo-controlled one-year intervention trial (the SAFIR study)

DEFF Research Database (Denmark)

Peters, Christian Daugaard; Kjærgaard, Krista Dybtved; Jensen, Jens Dam

2014-01-01

), stroke volume (SV), central blood volume (CBV), total peripheral resistance (TPR), mean arterial BP (MAP), and heart rate (HR) were measured within the first (HDSTART) and last (HDEND) 30 minutes during HD using the Transonic saline dilution technique. Results Eighty-two patients were randomised (placebo....../ARB: 41/41). Predialytic systolic BP decreased significantly, but similarly in both groups during the study period. The total number of IDH episodes was (placebo/ARB) 22/25 (P=0.7). Mean HDSTART and mean HDEND CO, SV, TPR, HR, and MAP were stable and similar in the two groups, whereas CBV increased...... equally and significantly over time. The mean intradialytic haemodynamic response showed decreased CO, SV, MAP, and CBV, whereas HR increased from HDSTART to HDEND. TPR did not change significantly. Overall, this pattern remained stable over time in both groups and there was no significant impact of ARB...

Genetic influences on ovulation of primary oocytes in LT/Sv strain mice.

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Everett, Clare A; Auchincloss, Catherine A; Kaufman, Matthew H; Abbott, Catherine M; West, John D

2004-11-01

A high proportion of LT/Sv strain oocytes arrest in meiotic metaphase I (MI) and are ovulated as diploid primary oocytes rather than haploid secondary oocytes. (Mus musculus castaneus x LT/SvKau)F1 x LT/SvKau backcross females were analysed for the proportion of oocytes that arrested in MI and typed by PCR for a panel of microsatellite DNA sequences (simple sequence repeat polymorphisms) that differed between strain LT/SvKau and M. m. castaneus. This provided a whole genome scan of 86 genetic markers distributed over all 19 autosomes and the X chromosome, and revealed genetic linkage of the MI arrest phenotype to markers on chromosomes 1 and 9. Identification of these two chromosomal regions should facilitate the identification of genes involved in mammalian oocyte maturation and the control of meiosis.

Cholinergic depletion and basal forebrain volume in primary progressive aphasia

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Jolien Schaeverbeke

2017-01-01

In the PPA group, only LV cases showed decreases in AChE activity levels compared to controls. Surprisingly, a substantial number of SV cases showed significant AChE activity increases compared to controls. BF volume did not correlate with AChE activity levels in PPA. To conclude, in our sample of PPA patients, LV but not SV was associated with cholinergic depletion. BF atrophy in PPA does not imply cholinergic depletion.

Stroke from systemic vascular disorders in Saudi children: The devastating role of hypernatremic dehydration

International Nuclear Information System (INIS)

Salih, Mustafa A.; Al-Jarallah, Ahmed A.; Zahraa, Jihad N.; Alorainy, Ibrahim A.; Hassan, Hamdy H.

2006-01-01

Systemic vascular disorders, leading to childhood stroke, include volume depletion or systemic hypotension and hypernatremic dehydration. We describe 3 cases of stroke following systemic vascular disorders. These were diagnosed during a prospective and retrospective study on childhood stroke, which included 104 patients. Post-gastroenteritis hypernatremic dehydration is an important, potentially preventable, cause of stroke in Saudi children. (author)

Properties of the simian virus 40 (SV40) large T antigens encoded by SV40 mutants with deletions in gene A.

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Cole, C N; Tornow, J; Clark, R; Tjian, R

1986-01-01

The biochemical properties of the large T antigens encoded by simian virus 40 (SV40) mutants with deletions at DdeI sites in the SV40 A gene were determined. Mutant large T antigens containing only the first 138 to 140 amino acids were unable to bind to the SV40 origin of DNA replication as were large T antigens containing at their COOH termini 96 or 97 amino acids encoded by the long open reading frame located between 0.22 and 0.165 map units (m.u.). All other mutant large T antigens were able to bind to the SV40 origin of replication. Mutants with in-phase deletions at 0.288 and 0.243 m.u. lacked ATPase activity, but ATPase activity was normal in mutants lacking origin-binding activity. The 627-amino acid large T antigen encoded by dlA2465, with a deletion at 0.219 m.u., was the smallest large T antigen displaying ATPase activity. Mutant large T antigens with the alternate 96- or 97-amino acid COOH terminus also lacked ATPase activity. All mutant large T antigens were found in the nuclei of infected cells; a small amount of large T with the alternate COOH terminus was also located in the cytoplasm. Mutant dlA2465 belonged to the same class of mutants as dlA2459. It was unable to form plaques on CV-1p cells at 37 or 32 degrees C but could form plaques on BSC-1 monolayers at 37 degrees C but not at 32 degrees C. It was positive for viral DNA replication and showed intracistronic complementation with any group A mutant whose large T antigen contained a normal carboxyl terminus. These findings and those of others suggest that both DNA binding and ATPase activity are required for the viral DNA replication function of large T antigen, that these two activities must be located on the same T antigen monomer, and that these two activities are performed by distinct domains of the polypeptide. These domains are distinct and separable from the domain affected by the mutation of dlA2465 and indicate that SV40 large T antigen is made up of at least three separate functional

General problems of metrology and indirect measuring in cardiology: error estimation criteria for indirect measurements of heart cycle phase durations

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Konstantine K. Mamberger

2012-11-01

Full Text Available Aims This paper treats general problems of metrology and indirect measurement methods in cardiology. It is aimed at an identification of error estimation criteria for indirect measurements of heart cycle phase durations. Materials and methods A comparative analysis of an ECG of the ascending aorta recorded with the use of the Hemodynamic Analyzer Cardiocode (HDA lead versus conventional V3, V4, V5, V6 lead system ECGs is presented herein. Criteria for heart cycle phase boundaries are identified with graphic mathematical differentiation. Stroke volumes of blood SV calculated on the basis of the HDA phase duration measurements vs. echocardiography data are compared herein. Results The comparative data obtained in the study show an averaged difference at the level of 1%. An innovative noninvasive measuring technology originally developed by a Russian R & D team offers measuring stroke volume of blood SV with a high accuracy. Conclusion In practice, it is necessary to take into account some possible errors in measurements caused by hardware. Special attention should be paid to systematic errors.

Guidance to Achieve Accurate Aggregate Quantitation in Biopharmaceuticals by SV-AUC.

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Arthur, Kelly K; Kendrick, Brent S; Gabrielson, John P

2015-01-01

The levels and types of aggregates present in protein biopharmaceuticals must be assessed during all stages of product development, manufacturing, and storage of the finished product. Routine monitoring of aggregate levels in biopharmaceuticals is typically achieved by size exclusion chromatography (SEC) due to its high precision, speed, robustness, and simplicity to operate. However, SEC is error prone and requires careful method development to ensure accuracy of reported aggregate levels. Sedimentation velocity analytical ultracentrifugation (SV-AUC) is an orthogonal technique that can be used to measure protein aggregation without many of the potential inaccuracies of SEC. In this chapter, we discuss applications of SV-AUC during biopharmaceutical development and how characteristics of the technique make it better suited for some applications than others. We then discuss the elements of a comprehensive analytical control strategy for SV-AUC. Successful implementation of these analytical control elements ensures that SV-AUC provides continued value over the long time frames necessary to bring biopharmaceuticals to market. © 2015 Elsevier Inc. All rights reserved.

High throughput testing of the SV40 Large T antigen binding to cellular p53 identifies putative drugs for the treatment of SV40-related cancers

International Nuclear Information System (INIS)

Carbone, Michele; Rudzinski, Jennifer; Bocchetta, Maurizio

2003-01-01

SV40 has been linked to some human malignancies, and the evidence that this virus plays a causative role in mesothelioma and brain tumors is mounting. The major SV40 oncoprotein is the Large tumor antigen (Tag). A key Tag transforming activity is connected to its capability to bind and inactivate cellular p53. In this study we developed an effective, high throughput, ELISA-based method to study Tag-p53 interaction in vitro. This assay allowed us to screen a chemical library and to identify a chemical inhibitor of the Tag binding to p53. We propose that our in vitro assay is a useful method to identify molecules that may be used as therapeutic agents for the treatment of SV40-related human cancers

Genome-Wide Comparative Functional Analyses Reveal Adaptations of Salmonella sv. Newport to a Plant Colonization Lifestyle

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Marcos H. de Moraes

2018-05-01

Full Text Available Outbreaks of salmonellosis linked to the consumption of vegetables have been disproportionately associated with strains of serovar Newport. We tested the hypothesis that strains of sv. Newport have evolved unique adaptations to persistence in plants that are not shared by strains of other Salmonella serovars. We used a genome-wide mutant screen to compare growth in tomato fruit of a sv. Newport strain from an outbreak traced to tomatoes, and a sv. Typhimurium strain from animals. Most genes in the sv. Newport strain that were selected during persistence in tomatoes were shared with, and similarly selected in, the sv. Typhimurium strain. Many of their functions are linked to central metabolism, including amino acid biosynthetic pathways, iron acquisition, and maintenance of cell structure. One exception was a greater need for the core genes involved in purine metabolism in sv. Typhimurium than in sv. Newport. We discovered a gene, papA, that was unique to sv. Newport and contributed to the strain’s fitness in tomatoes. The papA gene was present in about 25% of sv. Newport Group III genomes and generally absent from other Salmonella genomes. Homologs of papA were detected in the genomes of Pantoea, Dickeya, and Pectobacterium, members of the Enterobacteriacea family that can colonize both plants and animals.

Calculation of left ventricular volumes and ejection fraction from dynamic cardiac-gated 15O-water PET/CT: 5D-PET

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Jonny Nordström

2017-11-01

Full Text Available Abstract Background Quantitative measurement of myocardial blood flow (MBF is of increasing interest in the clinical assessment of patients with suspected coronary artery disease (CAD. 15O-water positron emission tomography (PET is considered the gold standard for non-invasive MBF measurements. However, calculation of left ventricular (LV volumes and ejection fraction (EF is not possible from standard 15O-water uptake images. The purpose of the present work was to investigate the possibility of calculating LV volumes and LVEF from cardiac-gated parametric blood volume (V B 15O-water images and from first pass (FP images. Sixteen patients with mitral or aortic regurgitation underwent an eight-gate dynamic cardiac-gated 15O-water PET/CT scan and cardiac MRI. V B and FP images were generated for each gate. Calculations of end-systolic volume (ESV, end-diastolic volume (EDV, stroke volume (SV and LVEF were performed with automatic segmentation of V B and FP images, using commercially available software. LV volumes and LVEF were calculated with surface-, count-, and volume-based methods, and the results were compared with gold standard MRI. Results Using V B images, high correlations between PET and MRI ESV (r = 0.89, p  0.86, p < 0.001. Conclusion Calculation of LV volumes and LVEF from dynamic 15O-water PET is feasible and shows good correlation with MRI. However, the analysis method is laborious, and future work is needed for more automation to make the method more easily applicable in a clinical setting.

Computed Tomography Perfusion Improves Diagnostic Accuracy in Acute Posterior Circulation Stroke.

Science.gov (United States)

Sporns, Peter; Schmidt, Rene; Minnerup, Jens; Dziewas, Rainer; Kemmling, André; Dittrich, Ralf; Zoubi, Tarek; Heermann, Philipp; Cnyrim, Christian; Schwindt, Wolfram; Heindel, Walter; Niederstadt, Thomas; Hanning, Uta

2016-01-01

Computed tomography perfusion (CTP) has a high diagnostic value in the detection of acute ischemic stroke in the anterior circulation. However, the diagnostic value in suspected posterior circulation (PC) stroke is uncertain, and whole brain volume perfusion is not yet in widespread use. We therefore studied the additional value of whole brain volume perfusion to non-contrast CT (NCCT) and CT angiography source images (CTA-SI) for infarct detection in patients with suspected acute ischemic PC stroke. This is a retrospective review of patients with suspected stroke in the PC in a database of our stroke center (n = 3,011) who underwent NCCT, CTA and CTP within 9 h after stroke onset and CT or MRI on follow-up. Images were evaluated for signs and pc-ASPECTS locations of ischemia. Three imaging models - A (NCCT), B (NCCT + CTA-SI) and C (NCCT + CTA-SI + CTP) - were compared with regard to the misclassification rate relative to gold standard (infarction in follow-up imaging) using the McNemar's test. Of 3,011 stroke patients, 267 patients had a suspected stroke in the PC and 188 patients (70.4%) evidenced a PC infarct on follow-up imaging. The sensitivity of Model C (76.6%) was higher compared with that of Model A (21.3%) and Model B (43.6%). CTP detected significantly more ischemic lesions, especially in the cerebellum, posterior cerebral artery territory and thalami. Our findings in a large cohort of consecutive patients show that CTP detects significantly more ischemic strokes in the PC than CTA and NCCT alone. © 2016 S. Karger AG, Basel.

Left atrial appendage morphology in patients with suspected cardiogenic stroke without known atrial fibrillation.

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Miika Korhonen

Full Text Available The left atrial appendage (LAA is the typical origin for intracardiac thrombus formation. Whether LAA morphology is associated with increased stroke/TIA risk is controversial and, if it does, which morphological type most predisposes to thrombus formation. We assessed LAA morphology in stroke patients with cryptogenic or suspected cardiogenic etiology and in age- and gender-matched healthy controls. LAA morphology and volume were analyzed by cardiac computed tomography in 111 patients (74 males; mean age 60 ± 11 years with acute ischemic stroke of cryptogenic or suspected cardiogenic etiology other than known atrial fibrillation (AF. A subgroup of 40 patients was compared to an age- and gender-matched control group of 40 healthy individuals (21 males in each; mean age 54 ± 9 years. LAA was classified into four morphology types (Cactus, ChickenWing, WindSock, CauliFlower modified with a quantitative qualifier. The proportions of LAA morphology types in the main stroke group, matched stroke subgroup, and control group were as follows: Cactus (9.0%, 5.0%, 20.0%, ChickenWing (23.4%, 37.5%, 10.0%, WindSock (47.7%, 35.0%, 67.5%, and CauliFlower (19.8%, 22.5%, 2.5%. The distribution of morphology types differed significantly (P<0.001 between the matched stroke subgroup and control group. The proportion of single-lobed LAA was significantly higher (P<0.001 in the matched stroke subgroup (55% than the control group (6%. LAA volumes were significantly larger (P<0.001 in both stroke study groups compared to controls patients. To conclude, LAA morphology differed significantly between stroke patients and controls, and single-lobed LAAs were overrepresented and LAA volume was larger in patients with acute ischemic stroke of cryptogenic or suspected cardiogenic etiology.

A method for partial volume correction of PET-imaged tumor heterogeneity using expectation maximization with a spatially varying point spread function

International Nuclear Information System (INIS)

Barbee, David L; Holden, James E; Nickles, Robert J; Jeraj, Robert; Flynn, Ryan T

2010-01-01

Tumor heterogeneities observed in positron emission tomography (PET) imaging are frequently compromised by partial volume effects which may affect treatment prognosis, assessment or future implementations such as biologically optimized treatment planning (dose painting). This paper presents a method for partial volume correction of PET-imaged heterogeneous tumors. A point source was scanned on a GE Discovery LS at positions of increasing radii from the scanner's center to obtain the spatially varying point spread function (PSF). PSF images were fit in three dimensions to Gaussian distributions using least squares optimization. Continuous expressions were devised for each Gaussian width as a function of radial distance, allowing for generation of the system PSF at any position in space. A spatially varying partial volume correction (SV-PVC) technique was developed using expectation maximization (EM) and a stopping criterion based on the method's correction matrix generated for each iteration. The SV-PVC was validated using a standard tumor phantom and a tumor heterogeneity phantom and was applied to a heterogeneous patient tumor. SV-PVC results were compared to results obtained from spatially invariant partial volume correction (SINV-PVC), which used directionally uniform three-dimensional kernels. SV-PVC of the standard tumor phantom increased the maximum observed sphere activity by 55 and 40% for 10 and 13 mm diameter spheres, respectively. Tumor heterogeneity phantom results demonstrated that as net changes in the EM correction matrix decreased below 35%, further iterations improved overall quantitative accuracy by less than 1%. SV-PVC of clinically observed tumors frequently exhibited changes of ±30% in regions of heterogeneity. The SV-PVC method implemented spatially varying kernel widths and automatically determined the number of iterations for optimal restoration, parameters which are arbitrarily chosen in SINV-PVC. Comparing SV-PVC to SINV-PVC demonstrated

Lowering bronchoaspiration rate in an acute stroke unit by means of a 2 volume/3 texture dysphagia screening test with pulsioximetry.

Science.gov (United States)

Cocho, D; Sagales, M; Cobo, M; Homs, I; Serra, J; Pou, M; Perez, G; Pujol, G; Tantinya, S; Bao, P; Aloy, A; Sabater, R; Gendre, J; Otermin, P

During acute stroke, 30% of all patients present dysphagia and 50% of that subgroup will experience bronchoaspiration. Our aim was to compare mortality and bronchoaspiration rates associated with the water test compared to those associated with a 2 volume/3 texture test controlled with pulse oximetry (2v/3t-P test) in our stroke unit. Over a 5-year period, we performed a prospective analysis of all consecutive acute ischaemic stroke patients hospitalised in the Stroke Unit. Dysphagia was evaluated using the water test between 2008 and 2010 (group 0 or G0), and the 2v/3t-P test (group 1 or G1) between 2011 and 2012. We analysed demographic data, vascular risk factors, neurological deficit on the NIHSS, aetiological subtype according to TOAST criteria, clinical subtype according to the Oxfordshire classification, prevalence of dysphagia, percentage of patients with bronchoaspiration, and mortality. We examined 418 patients with acute stroke (G0=275, G1=143). There were significant differences between the 2 groups regarding the percentage of patients with TACI (17% in G0 vs. 29% in G1, P=.005) and median NIHSS score (4 points in G0 vs. 7 points in G1, P=.003). Since adopting the new swallowing test, we detected a non-significant increase in the percentage of dysphagia (22% in G0 vs. 25% in G1, P=.4), lower mortality (1.7% in G0 vs. 0.7% in G1, P=.3) and a significant decrease in the bronchoaspiration rate (6.2% in G0 vs. 2.1% in G1, P=.05). Compared to the water test used for dysphagia screening, the new 2v/3t-P test lowered bronchoaspiration rates in acute stroke patients. Copyright © 2014 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Role of Acute Lesion Topography in Initial Ischemic Stroke Severity and Long-Term Functional Outcomes.

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Wu, Ona; Cloonan, Lisa; Mocking, Steven J T; Bouts, Mark J R J; Copen, William A; Cougo-Pinto, Pedro T; Fitzpatrick, Kaitlin; Kanakis, Allison; Schaefer, Pamela W; Rosand, Jonathan; Furie, Karen L; Rost, Natalia S

2015-09-01

Acute infarct volume, often proposed as a biomarker for evaluating novel interventions for acute ischemic stroke, correlates only moderately with traditional clinical end points, such as the modified Rankin Scale. We hypothesized that the topography of acute stroke lesions on diffusion-weighted magnetic resonance imaging may provide further information with regard to presenting stroke severity and long-term functional outcomes. Data from a prospective stroke repository were limited to acute ischemic stroke subjects with magnetic resonance imaging completed within 48 hours from last known well, admission NIH Stroke Scale (NIHSS), and 3-to-6 months modified Rankin Scale scores. Using voxel-based lesion symptom mapping techniques, including age, sex, and diffusion-weighted magnetic resonance imaging lesion volume as covariates, statistical maps were calculated to determine the significance of lesion location for clinical outcome and admission stroke severity. Four hundred ninety subjects were analyzed. Acute stroke lesions in the left hemisphere were associated with more severe NIHSS at admission and poor modified Rankin Scale at 3 to 6 months. Specifically, injury to white matter (corona radiata, internal and external capsules, superior longitudinal fasciculus, and uncinate fasciculus), postcentral gyrus, putamen, and operculum were implicated in poor modified Rankin Scale. More severe NIHSS involved these regions, as well as the amygdala, caudate, pallidum, inferior frontal gyrus, insula, and precentral gyrus. Acute lesion topography provides important insights into anatomic correlates of admission stroke severity and poststroke outcomes. Future models that account for infarct location in addition to diffusion-weighted magnetic resonance imaging volume may improve stroke outcome prediction and identify patients likely to benefit from aggressive acute intervention and personalized rehabilitation strategies. © 2015 American Heart Association, Inc.

Ipsilateral hippocampal atrophy is associated with long-term memory dysfunction after ischemic stroke in young adults

NARCIS (Netherlands)

Schaapsmeerders, P.; Uden, I.W.M. van; Tuladhar, A.M.; Maaijwee, N.A.M.M.; Dijk, E.J. van; Rutten-Jacobs, L.C.A.; Arntz, R.M.; Schoonderwaldt, H.C.; Dorresteijn, L.D.A.; Leeuw, H.F. de; Kessels, R.P.C.

2015-01-01

Memory impairment after stroke in young adults is poorly understood. In elderly stroke survivors memory impairments and the concomitant loss of hippocampal volume are usually explained by coexisting neurodegenerative disease (e.g., amyloid pathology) in interaction with stroke. However,

Lower Ipsilateral Hippocampal Integrity after Ischemic Stroke in Young Adults: A Long-Term Follow-Up Study

NARCIS (Netherlands)

Schaapsmeerders, P.; Tuladhar, A.M.; Maaijwee, N.A.M.M.; Rutten-Jacobs, L.C.A.; Arntz, R.M.; Schoonderwaldt, H.C.; Dorresteijn, L.D.A.; Dijk, E.J. van; Kessels, R.P.C.; Leeuw, H.F. de

2015-01-01

Background and purpose Memory impairment after stroke is poorly understood as stroke rarely occurs in the hippocampus. Previous studies have observed smaller ipsilateral hippocampal volumes after stroke compared with controls. Possibly, these findings on macroscopic level are not the first

Lower Ipsilateral Hippocampal Integrity after Ischemic Stroke in Young Adults: A Long-Term Follow-Up Study

NARCIS (Netherlands)

Schaapsmeerders, P.; Tuladhar, A.M.; Maaijwee, N.A.M.M.; Rutten-Jacobs, L.C.A.; Arntz, R.M.; Schoonderwaldt, H.C.; Dorresteijn, L.D.; Dijk, E.J. van; Kessels, R.P.C.; Leeuw, F.E. de

2015-01-01

BACKGROUND AND PURPOSE: Memory impairment after stroke is poorly understood as stroke rarely occurs in the hippocampus. Previous studies have observed smaller ipsilateral hippocampal volumes after stroke compared with controls. Possibly, these findings on macroscopic level are not the first

Effects of electroacupuncture on recent stroke inpatients with incomplete bladder emptying: a preliminary study

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Yu KW

2012-11-01

Full Text Available Kuo-Wei Yu,1,* Chien-Lin Lin,1,2 Chun-Chuang Hung,3 Eric Chieh-Lung Chou,4 Yueh-Ling Hsieh,5 Te-Mao Li,2,3,* Li-Wei Chou1,2,61Department of Physical Medicine and Rehabilitation, China Medical University Hospital, Taichung, Taiwan; 2School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; 3Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan; 4Department of Urology, China Medical University Hospital, Taichung, Taiwan; 5Department of Physical Therapy, China Medical University, Taichung, Taiwan; 6Acupuncture Research Center, China Medical University, Taichung, Taiwan*These authors contributed equally to this workBackground: Incomplete bladder emptying (IBE is defined as having a postvoid residual (PVR urine volume greater than 100 mL for 2 consecutive days. IBE is common in stroke patients and could necessitate indwelling or intermittent catheterization. The condition is correlated with urinary tract infections, which could impede rehabilitation progress and increase medical costs. Treatment for patients with IBE includes bladder retraining, biofeedback, medication, and botulinum toxin injection, but none of these interventions are completely effective.Methods: All patients with acute stroke who were admitted to the rehabilitation ward between August 2010 and April 2011 were included in the study and their PVR urine volume was checked. Electroacupuncture (EA; 1 Hz, 15 minutes was performed on the acupoints Sanyinjiao (SP6, Ciliao (BL32, and Pangguangshu (BL28 of stroke patients with IBE for a total of ten treatments (five times a week for 2 weeks. Bladder diaries, which included the spontaneous voiding and PVR urine volumes, were recorded during the course of treatment.Results: The presence of IBE was not related to sex, history of diabetes mellitus, stroke type (hemorrhagic or ischemic, or stroke location (P > 0.05. Among the 49 patients in the study, nine (18% had IBE

Prediction of acute cardiac rejection by changes in left ventricular volumes

International Nuclear Information System (INIS)

Novitzky, D.; Cooper, D.K.; Boniaszczuk, J.

1988-01-01

Sixteen patients underwent heart transplantation (11 orthotopic, five heterotopic). Monitoring for acute rejection was by both endomyocardial biopsy (EMB) and multigated equilibrium blood pool scanning with technetium 99m-labelled red blood cells. From the scans information was obtained on left ventricular volumes (stroke, end-diastolic, and end-systolic), ejection fraction, and heart rate. Studies (208) were made in the 16 patients. There was a highly significant correlation between the reduction in stroke volume and end-diastolic volume (and a less significant correlation in end-systolic volume) and increasing acute rejection seen on EMB. Heart rate and ejection fraction did not correlate with the development of acute rejection. Correlation of a combination of changes in stroke volume and end-diastolic volume with EMB showed a sensitivity of 85% and a specificity of 96%. Radionuclide scanning is therefore a useful noninvasive tool for monitoring acute rejection

Synaptic vesicle glycoprotein 2C (SV2C) modulates dopamine release and is disrupted in Parkinson disease.

Science.gov (United States)

Dunn, Amy R; Stout, Kristen A; Ozawa, Minagi; Lohr, Kelly M; Hoffman, Carlie A; Bernstein, Alison I; Li, Yingjie; Wang, Minzheng; Sgobio, Carmelo; Sastry, Namratha; Cai, Huaibin; Caudle, W Michael; Miller, Gary W

2017-03-14

Members of the synaptic vesicle glycoprotein 2 (SV2) family of proteins are involved in synaptic function throughout the brain. The ubiquitously expressed SV2A has been widely implicated in epilepsy, although SV2C with its restricted basal ganglia distribution is poorly characterized. SV2C is emerging as a potentially relevant protein in Parkinson disease (PD), because it is a genetic modifier of sensitivity to l-DOPA and of nicotine neuroprotection in PD. Here we identify SV2C as a mediator of dopamine homeostasis and report that disrupted expression of SV2C within the basal ganglia is a pathological feature of PD. Genetic deletion of SV2C leads to reduced dopamine release in the dorsal striatum as measured by fast-scan cyclic voltammetry, reduced striatal dopamine content, disrupted α-synuclein expression, deficits in motor function, and alterations in neurochemical effects of nicotine. Furthermore, SV2C expression is dramatically altered in postmortem brain tissue from PD cases but not in Alzheimer disease, progressive supranuclear palsy, or multiple system atrophy. This disruption was paralleled in mice overexpressing mutated α-synuclein. These data establish SV2C as a mediator of dopamine neuron function and suggest that SV2C disruption is a unique feature of PD that likely contributes to dopaminergic dysfunction.

Stroke infarct volume estimation in fixed tissue

DEFF Research Database (Denmark)

Bay, Vibeke; Kjølby, Birgitte F; Iversen, Nina K

2018-01-01

be investigated in fixed tissue and therefore allows a more direct comparison between lesion volumes from MRI and histology. Additionally, the larger MKT infarct lesion indicates that MKT do provide increased sensitivity to microstructural changes in the lesion area compared to MD....... and prepared. The infarct was clearly visible in both MD and MKT maps. The MKT lesion volume was roughly 31% larger than the MD lesion volume. Subsequent histological analysis (hematoxylin) revealed similar lesion volumes to MD. Our study shows that structural components underlying the MD/MKT mismatch can...

Extravascular Lung Water Does Not Increase in Hypovolemic Patients after a Fluid-Loading Protocol Guided by the Stroke Volume Variation

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Carlos Ferrando

2012-01-01

Full Text Available Introduction. Circulatory failure secondary to hypovolemia is a common situation in critical care patients. Volume replacement is the first option for the treatment of hypovolemia. A possible complication of volume loading is pulmonary edema, quantified at the bedside by the measurement of extravascular lung water index (ELWI. ELWI predicts progression to acute lung injury (ALI in patients with risk factors for developing it. The aim of this study was to assess whether fluid loading guided by the stroke volume variation (SVV, in patients presumed to be hypovolemic, increased ELWI or not. Methods. Prospective study of 17 consecutive postoperative, fully mechanically ventilated patients diagnosed with circulatory failure secondary to presumed hypovolemia were included. Cardiac index (CI, ELWI, SVV, and global end-diastolic volume index (GEDI were determined using the transpulmonary thermodilution technique during the first 12 hours after fluid loading. Volume replacement was done with a strict hemodynamic protocol. Results. Fluid loading produced a significant increase in CI and a decrease in SVV. ELWI did not increase. No correlation was found between the amount of fluids administered and the change in ELWI. Conclusion. Fluid loading guided by SVV in hypovolemic and fully mechanically ventilated patients in sinus rhythm does not increase ELWI.

Visualization of SV2A conformations in situ by the use of Protein Tomography

International Nuclear Information System (INIS)

Lynch, Berkley A.; Matagne, Alain; Braennstroem, Annika; Euler, Anne von; Jansson, Magnus; Hauzenberger, Elenor; Soederhaell, J. Arvid

2008-01-01

The synaptic vesicle protein 2A (SV2A), the brain-binding site of the anti-epileptic drug levetiracetam (LEV), has been characterized by Protein Tomography TM . We identified two major conformations of SV2A in mouse brain tissue: first, a compact, funnel-structure with a pore-like opening towards the cytoplasm; second, a more open, V-shaped structure with a cleft-like opening towards the intravesicular space. The large differences between these conformations suggest a high degree of flexibility and support a valve-like mechanism consistent with the postulated transporter role of SV2A. These two conformations are represented both in samples treated with LEV, and in saline-treated samples, which indicates that LEV binding does not cause a large-scale conformational change of SV2A, or lock a specific conformational state of the protein. This study provides the first direct structural data on SV2A, and supports a transporter function suggested by sequence homology to MFS class of transporter proteins

Hemodynamic changes during robotic radical prostatectomy

Directory of Open Access Journals (Sweden)

Vanlal Darlong

2012-01-01

Full Text Available Background: Effect on hemodynamic changes and experience of robot-assisted laparoscopic radical prostatectomy (RALRP in steep Trendelenburg position (45° with high-pressure CO 2 pneumoperitoneum is very limited. Therefore, we planned this prospective clinical trial to study the effect of steep Tredelenburg position with high-pressure CO 2 pneumoperitoneum on hemodynamic parameters in a patient undergoing RALRP using FloTrac/Vigileo™1.10. Methods: After ethical approval and informed consent, 15 patients scheduled for RALRP were included in the study. In the operation room, after attaching standard monitors, the radial artery was cannulated. Anesthesia was induced with fentanyl (2 μg/kg and thiopentone (4-7 mg/kg, and tracheal intubation was facilitated by vecuronium bromide (0.1 mg/kg. The patient′s right internal jugular vein was cannulated and the Pre Sep™ central venous oximetry catheter was connected to it. Anesthesia was maintained with isoflurane in oxygen and nitrous oxide and intermittent boluses of vecuronium. Intermittent positive-pressure ventilation was provided to maintain normocapnea. After CO 2 pneumoperitoneum, position of the patient was gradually changed to 45° Trendelenburg over 5 min. The robot was then docked and the robot-assisted surgery started. Intraoperative monitoring included central venous pressure (CVP, stroke volume (SV, stroke volume variation (SVV, cardiac output (CO, cardiac index (CI and central venous oxygen saturation (ScvO 2 . Results: After induction of anesthesia, heart rate (HR, SV, CO and CI were decreased significantly from the baseline value (P>0.05. SV, CO and CI further decreased significantly after creating pneumoperitoneum (P>0.05. At the 45° Trendelenburg position, HR, SV, CO and CI were significantly decreased compared with baseline. Thereafter, CO and CI were persistently low throughout the 45° Trendelenburg position (P=0.001. HR at 20 min and 1 h, SV and mean arterial blood pressure

Aanvullend commentaar op art. 511a Sv

NARCIS (Netherlands)

van Laanen, F.; Melai, A.L.; Groenhuijsen, M.S.

2005-01-01

Schr. geeft een actueel wetenschappelijk commentaar op art. 511a Sv. Daarin komt met name de hedendaagse werkingssfeer aan de orde van deze bepaling, waarin is gesteld dat de berechting van strafbare feiten die ingevolge enige wet aan de burgerlijke rechter is opgedragen, ter terechtzitting van de

Cardiac MRI in children and adolescents who have undergone surgical repair of right-sided congenital heart disease. Automated left ventricular volumes and function analysis and effects of different manual adjustments

Energy Technology Data Exchange (ETDEWEB)

Rompel, O.; Janka, R.; May, M.S.; Lell, M.M.; Uder, M.; Hammon, M. [University Hospital Erlangen (Germany). Dept. of Radiology; Gloeckler, M.; Dittrich, S. [University Hospital Erlangen (Germany). Dept. of Pediatric Cardiology; Cesnjevar, R. [University Hospital Erlangen (Germany). Dept. of Pediatric Cardiac Surgery

2015-12-15

To evaluate automated segmentation and the effects of different manual adjustments regarding left ventricular parameter quantification in cardiac magnetic resonance (MR) data on children and adolescents who have undergone surgical repair of right-sided congenital heart disease (CHD). Dedicated software (syngo.via, Siemens AG) was used to automatically segment and/or manually adjust the end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), myocardial mass (MM) and ejection fraction (EF) before/after manual apex/base adjustment (ADJ-step 1) and after manual apex/base/myocardial contour adjustment (ADJ-step 2; reference standard). MR data of 40 patients (13.1 ± 3.1y, 4-17y) with repaired CHD with decreased pulmonary blood flow (CHD-DPBF) were evaluated. Intra- and inter-rater reliability was determined for 10 randomly selected patients. The software correctly detected the left ventricle in 38/40 (95 %) patients. EDV after automated segmentation: 119.1 ± 44.0ml; after ADJ-step 1: 115.8 ± 39.5 ml; after ADJ-step 2: 116.2 ± 39.4 ml. The corresponding results for ESV were 52.0 ± 18.5/49.6 ± 16.9/49.7 ± 16.4 ml; for SV 67.1 ± 28.5/66.2 ± 25.4/66.5 ± 25.5 ml; for EF 55.5 ± 7.3/56.7 ± 6.6/56.7 ± 6.3%; for MM 83.7 ± 35.9/76.2 ± 28.3/74.6 ± 27.2 g. Significant differences were found for ESV/MM/EF comparing the automated segmentation results with these after ADJ-step 1 and ADJ-step 2. No significant differences were found when comparing all results of ADJ-step 1 and ADJ-step 2 or when comparing EDV/SV results. Intra- and inter-rater reliability was excellent. The mean time effort was 63.4 ± 6.9 s for the automated segmentation, 74.2 ± 8.9 s for ADJ-step 1 and 269.5 ± 39.4 s for ADJ-step 2. Automated left ventricular volumes and function analysis in children and adolescents with surgically treated CHD proved to be feasible with excellent intra- and inter-rater reliability. Automated segmentation with manual apex/base adjustment provided

Cardiac MRI in children and adolescents who have undergone surgical repair of right-sided congenital heart disease. Automated left ventricular volumes and function analysis and effects of different manual adjustments

International Nuclear Information System (INIS)

Rompel, O.; Janka, R.; May, M.S.; Lell, M.M.; Uder, M.; Hammon, M.; Gloeckler, M.; Dittrich, S.; Cesnjevar, R.

2015-01-01

To evaluate automated segmentation and the effects of different manual adjustments regarding left ventricular parameter quantification in cardiac magnetic resonance (MR) data on children and adolescents who have undergone surgical repair of right-sided congenital heart disease (CHD). Dedicated software (syngo.via, Siemens AG) was used to automatically segment and/or manually adjust the end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), myocardial mass (MM) and ejection fraction (EF) before/after manual apex/base adjustment (ADJ-step 1) and after manual apex/base/myocardial contour adjustment (ADJ-step 2; reference standard). MR data of 40 patients (13.1 ± 3.1y, 4-17y) with repaired CHD with decreased pulmonary blood flow (CHD-DPBF) were evaluated. Intra- and inter-rater reliability was determined for 10 randomly selected patients. The software correctly detected the left ventricle in 38/40 (95 %) patients. EDV after automated segmentation: 119.1 ± 44.0ml; after ADJ-step 1: 115.8 ± 39.5 ml; after ADJ-step 2: 116.2 ± 39.4 ml. The corresponding results for ESV were 52.0 ± 18.5/49.6 ± 16.9/49.7 ± 16.4 ml; for SV 67.1 ± 28.5/66.2 ± 25.4/66.5 ± 25.5 ml; for EF 55.5 ± 7.3/56.7 ± 6.6/56.7 ± 6.3%; for MM 83.7 ± 35.9/76.2 ± 28.3/74.6 ± 27.2 g. Significant differences were found for ESV/MM/EF comparing the automated segmentation results with these after ADJ-step 1 and ADJ-step 2. No significant differences were found when comparing all results of ADJ-step 1 and ADJ-step 2 or when comparing EDV/SV results. Intra- and inter-rater reliability was excellent. The mean time effort was 63.4 ± 6.9 s for the automated segmentation, 74.2 ± 8.9 s for ADJ-step 1 and 269.5 ± 39.4 s for ADJ-step 2. Automated left ventricular volumes and function analysis in children and adolescents with surgically treated CHD proved to be feasible with excellent intra- and inter-rater reliability. Automated segmentation with manual apex/base adjustment provided

Left ventricular pressure and volume data acquisition and analysis using LabVIEW.

Science.gov (United States)

Cassidy, S C; Teitel, D F

1997-03-01

To automate analysis of left ventricular pressure-volume data, we used LabVIEW to create applications that digitize and display data recorded from conductance and manometric catheters. Applications separate data into cardiac cycles, calculate parallel conductance, and calculate indices of left ventricular function, including end-systolic elastance, preload-recruitable stroke work, stroke volume, ejection fraction, stroke work, maximum and minimum derivative of ventricular pressure, heart rate, indices of relaxation, peak filling rate, and ventricular chamber stiffness. Pressure-volume loops can be graphically displayed. These analyses are exported to a text-file. These applications have simplified and automated the process of evaluating ventricular function.

Cardiorespiratory fitness, cognition and brain structure after TIA or minor ischemic stroke.

Science.gov (United States)

Boss, H Myrthe; Van Schaik, Sander M; Witkamp, Theo D; Geerlings, Mirjam I; Weinstein, Henry C; Van den Berg-Vos, Renske M

2017-10-01

Background It is not known whether cardiorespiratory fitness is associated with better cognitive performance and brain structure in patients with a TIA or minor ischemic stroke. Aims To examine the association between cardiorespiratory fitness, cognition and brain structure in patients with a TIA and minor stroke. Methods The study population consisted of patients with a TIA or minor stroke with a baseline measurement of the peak oxygen consumption, a MRI scan of brain and neuropsychological assessment. Composite z-scores were calculated for the cognitive domains attention, memory and executive functioning. White matter hyperintensities, microbleeds and lacunes were rated visually. The mean apparent diffusion coefficient was measured in regions of interest in frontal and occipital white matter and in the centrum semiovale as a marker of white matter structure. Normalized brain volumes were estimated by use of Statistical Parametric Mapping. Results In 84 included patients, linear regression analysis adjusted for age, sex and education showed that a higher peak oxygen consumption was associated with higher cognitive z-scores, a larger grey matter volume (B = 0.15 (95% CI 0.05; 0.26)) and a lower mean apparent diffusion coefficient (B = -.004 (95% CI -.007; -.001)). We found no association between the peak oxygen consumption and severe white matter hyperintensities, microbleeds, lacunes and total brain volume. Conclusions These data suggest that cardiorespiratory fitness is associated with better cognitive performance, greater grey matter volume and greater integrity of the white matter in patients with a TIA or minor ischemic stroke. Further prospective trials are necessary to define the effect of cardiorespiratory fitness on cognition and brain structure in patients with TIA or minor stroke.

The Influence of SV40 polyA on Gene Expression of Baculovirus Expression Vector Systems.

Directory of Open Access Journals (Sweden)

Tamer Z Salem

Full Text Available The simian virus 40 polyadenylation signal (SV40 polyA has been routinely inserted downstream of the polyhedrin promoter in many baculovirus expression vector systems (BEVS. In the baculovirus prototype Autographa californica multiple nucleopolyhedrovirus (AcMNPV, the polyhedrin promoter (very late promoter transcribes its gene by a viral RNA polymerase therefore there is no supporting evidence that SV40 polyA is required for the proper gene expression under the polyhedrin promoter. Moreover, the effect of the SV40 polyA sequence on the polyhedrin promoter activity has not been tested either at its natural polyhedrin locus or in other loci in the viral genome. In order to test the significance of adding the SV40 polyA sequence on gene expression, the expression of the enhanced green fluorescent protein (egfp was evaluated with and without the presence of SV40 polyA under the control of the polyhedrin promoter at different genomic loci (polyherin, ecdysteroid UDP-glucosyltransferase (egt, and gp37. In this study, spectrofluorometry and western blot showed reduction of EGFP protein for all recombinant viruses with SV40 polyA, whereas qPCR showed an increase in the egfp mRNA levels. Therefore, we conclude that SV40 polyA increases mRNA levels but decreases protein production in the BEVS when the polyhedrin promoter is used at different loci. This work suggests that SV40 polyA in BEVSs should be replaced by an AcMNPV late gene polyA for optimal protein production or left untouched for optimal RNA production (RNA interference applications.

The Influence of SV40 polyA on Gene Expression of Baculovirus Expression Vector Systems

Science.gov (United States)

Salem, Tamer Z.; Seaborn, Craig P.; Turney, Colin M.; Xue, Jianli; Shang, Hui; Cheng, Xiao-Wen

2015-01-01

The simian virus 40 polyadenylation signal (SV40 polyA) has been routinely inserted downstream of the polyhedrin promoter in many baculovirus expression vector systems (BEVS). In the baculovirus prototype Autographa californica multiple nucleopolyhedrovirus (AcMNPV), the polyhedrin promoter (very late promoter) transcribes its gene by a viral RNA polymerase therefore there is no supporting evidence that SV40 polyA is required for the proper gene expression under the polyhedrin promoter. Moreover, the effect of the SV40 polyA sequence on the polyhedrin promoter activity has not been tested either at its natural polyhedrin locus or in other loci in the viral genome. In order to test the significance of adding the SV40 polyA sequence on gene expression, the expression of the enhanced green fluorescent protein (egfp) was evaluated with and without the presence of SV40 polyA under the control of the polyhedrin promoter at different genomic loci (polyherin, ecdysteroid UDP-glucosyltransferase (egt), and gp37). In this study, spectrofluorometry and western blot showed reduction of EGFP protein for all recombinant viruses with SV40 polyA, whereas qPCR showed an increase in the egfp mRNA levels. Therefore, we conclude that SV40 polyA increases mRNA levels but decreases protein production in the BEVS when the polyhedrin promoter is used at different loci. This work suggests that SV40 polyA in BEVSs should be replaced by an AcMNPV late gene polyA for optimal protein production or left untouched for optimal RNA production (RNA interference applications). PMID:26659470

Worse stroke outcome in atrial fibrillation is explained by more severe hypoperfusion, infarct growth, and hemorrhagic transformation.

Science.gov (United States)

Tu, Hans T H; Campbell, Bruce C V; Christensen, Soren; Desmond, Patricia M; De Silva, Deidre A; Parsons, Mark W; Churilov, Leonid; Lansberg, Maarten G; Mlynash, Michael; Olivot, Jean-Marc; Straka, Matus; Bammer, Roland; Albers, Gregory W; Donnan, Geoffrey A; Davis, Stephen M

2015-06-01

Atrial fibrillation is associated with greater baseline neurological impairment and worse outcomes following ischemic stroke. Previous studies suggest that greater volumes of more severe baseline hypoperfusion in patients with history of atrial fibrillation may explain this association. We further investigated this association by comparing patients with and without atrial fibrillation on initial examination following stroke using pooled multimodal magnetic resonance imaging and clinical data from the Echoplanar Imaging Thrombolytic Evaluation Trial and the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution studies. Echoplanar Imaging Thrombolytic Evaluation Trial was a trial of 101 ischemic stroke patients randomized to intravenous tissue plasminogen activator or placebo, and Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution was a prospective cohort of 74 ischemic stroke patients treated with intravenous tissue plasminogen activator at three to six hours following symptom onset. Patients underwent multimodal magnetic resonance imaging before treatment, at three to five days and three-months after stroke in Echoplanar Imaging Thrombolytic Evaluation Trial; before treatment, three to six hours after treatment and one-month after stroke in Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution. Patients were assessed with the National Institutes of Health Stroke Scale and the modified Rankin scale before treatment and at three-months after stroke. Patients were categorized into definite atrial fibrillation (present on initial examination), probable atrial fibrillation (history but no atrial fibrillation on initial examination), and no atrial fibrillation. Perfusion data were reprocessed with automated magnetic resonance imaging analysis software (RAPID, Stanford University, Stanford, CA, USA). Hypoperfusion volumes were defined using time to maximum delays in two-second increments from >4 to

Acute MRI changes in progressive ischemic stroke

DEFF Research Database (Denmark)

Kalowska, E.; Rostrup, E.; Rosenbaum, S.

2008-01-01

as a permanent decrease of >or=3 Scandinavian Stroke Scale (SSS) points for speech or >or=2 SSS points for consciousness or >or=2 SSS points for limb strength, when assessed at baseline compared to the day after admission and daily during the following week. Patients were followed up on day 90 and assessed using...... the modified Rankin Scale, Barthel Index and SSS score. Patients with and without SIP were compared using both clinical and MRI data obtained on admission, on day 7 and after 3 months. RESULTS: Fifteen patients (37%) developed SIP. Increased DWI lesion volume on day 7 in all strokes was associated with SIP...... (chi(2), p = 0.005). All lacunar infarcts with a DWI volume >1.5 cm(3) at baseline (4 patients) developed SIP (p SSS scores with severer symptoms than non-SIP patients (p Udgivelsesdato: 2008...

Interleukin-6 is increased in plasma and cerebrospinal fluid of community-dwelling domestic dogs with acute ischaemic stroke

DEFF Research Database (Denmark)

Gredal, Hanne; Thomsen, Barbara B; Boza-Serrano, Antonio

2017-01-01

and cerebrospinal fluid (CSF) in dogs with acute ischaemic stroke and to search for correlations between infarct volume and cytokine concentrations. Blood and CSF were collected from dogs less than 72 h after a spontaneous ischaemic stroke. Infarct volumes were estimated on MRIs. Interleukin (IL)-2, IL-6, IL-8, IL...

Quantitative assessment of global and regional air trappings using non-rigid registration and regional specific volume change of inspiratory/expiratory CT scans: Studies on healthy volunteers and asthmatics

International Nuclear Information System (INIS)

Lee, Eun Sol; Seo, Joon Beom; Lee, Hyun Joo; Chae, Eun Jin; Lee, Sang Min; Oh, Sang Young; Kim, Nam Kug

2015-01-01

The purpose of this study was to compare air trapping in healthy volunteers with asthmatics using pulmonary function test and quantitative data, such as specific volume change from paired inspiratory CT and registered expiratory CT. Sixteen healthy volunteers and 9 asthmatics underwent paired inspiratory/expiratory CT. DeltaSV, which represents the ratio of air fraction released after exhalation, was measured with paired inspiratory and anatomically registered expiratory CT scans. Air trapping indexes, DeltaSV0.4 and DeltaSV0.5, were defined as volume fraction of lung below 0.4 and 0.5 DeltaSV, respectively. To assess the gravity effect of air-trapping, DeltaSV values of anterior and posterior lung at three different levels were measured and DeltaSV ratio of anterior lung to posterior lung was calculated. Color-coded DeltaSV map of the whole lung was generated and visually assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 were compared between healthy volunteers and asthmatics. In asthmatics, correlation between air trapping indexes and clinical parameters were assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 in asthmatics were significantly higher than those in healthy volunteer group (all p < 0.05). DeltaSV values in posterior lung in asthmatics were significantly higher than those in healthy volunteer group (p = 0.049). In asthmatics, air trapping indexes, such as DeltaSV0.5 and DeltaSV0.4, showed negative strong correlation with FEF25-75, FEV1, and FEV1/FVC. DeltaSV map of asthmatics showed abnormal geographic pattern in 5 patients (55.6%) and disappearance of anterior-posterior gradient in 3 patients (33.3%). Quantitative assessment of DeltaSV (the ratio of air fraction released after exhalation) shows the difference in extent of air trapping between health volunteers and asthmatics.

Quantitative assessment of global and regional air trappings using non-rigid registration and regional specific volume change of inspiratory/expiratory CT scans: Studies on healthy volunteers and asthmatics

Energy Technology Data Exchange (ETDEWEB)

Lee, Eun Sol; Seo, Joon Beom; Lee, Hyun Joo; Chae, Eun Jin; Lee, Sang Min; Oh, Sang Young; Kim, Nam Kug [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

2015-06-15

The purpose of this study was to compare air trapping in healthy volunteers with asthmatics using pulmonary function test and quantitative data, such as specific volume change from paired inspiratory CT and registered expiratory CT. Sixteen healthy volunteers and 9 asthmatics underwent paired inspiratory/expiratory CT. DeltaSV, which represents the ratio of air fraction released after exhalation, was measured with paired inspiratory and anatomically registered expiratory CT scans. Air trapping indexes, DeltaSV0.4 and DeltaSV0.5, were defined as volume fraction of lung below 0.4 and 0.5 DeltaSV, respectively. To assess the gravity effect of air-trapping, DeltaSV values of anterior and posterior lung at three different levels were measured and DeltaSV ratio of anterior lung to posterior lung was calculated. Color-coded DeltaSV map of the whole lung was generated and visually assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 were compared between healthy volunteers and asthmatics. In asthmatics, correlation between air trapping indexes and clinical parameters were assessed. Mean DeltaSV, DeltaSV0.4, and DeltaSV0.5 in asthmatics were significantly higher than those in healthy volunteer group (all p < 0.05). DeltaSV values in posterior lung in asthmatics were significantly higher than those in healthy volunteer group (p = 0.049). In asthmatics, air trapping indexes, such as DeltaSV0.5 and DeltaSV0.4, showed negative strong correlation with FEF25-75, FEV1, and FEV1/FVC. DeltaSV map of asthmatics showed abnormal geographic pattern in 5 patients (55.6%) and disappearance of anterior-posterior gradient in 3 patients (33.3%). Quantitative assessment of DeltaSV (the ratio of air fraction released after exhalation) shows the difference in extent of air trapping between health volunteers and asthmatics.

Mean platelet volume and mean platelet volume/platelet count ratio

African Journals Online (AJOL)

Amira M. Elsayed

2016-03-30

Mar 30, 2016 ... The aim of this study was to compare the MPV and mean platelet volume/platelet count ... brain stroke, both in the acute phase and long after disease.17 ... males, while the healthy controls comprised 12 females and 8.

Stroke Lesions in a Large Upper Limb Rehabilitation Trial Cohort Rarely Match Lesions in Common Preclinical Models

Science.gov (United States)

Edwardson, Matthew A.; Wang, Ximing; Liu, Brent; Ding, Li; Lane, Christianne J.; Park, Caron; Nelsen, Monica A.; Jones, Theresa A; Wolf, Steven L; Winstein, Carolee J; Dromerick, Alexander W.

2017-01-01

Background Stroke patients with mild-moderate upper extremity (UE) motor impairments and minimal sensory and cognitive deficits provide a useful model to study recovery and improve rehabilitation. Laboratory-based investigators use lesioning techniques for similar goals. Objective Determine whether stroke lesions in an UE rehabilitation trial cohort match lesions from the preclinical stroke recovery models used to drive translational research. Methods Clinical neuroimages from 297 participants enrolled in the Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) study were reviewed. Images were characterized based on lesion type (ischemic or hemorrhagic), volume, vascular territory, depth (cortical gray matter, cortical white matter, subcortical), old strokes, and leukoaraiosis. Lesions were compared with those of preclinical stroke models commonly used to study upper limb recovery. Results Among the ischemic stroke participants, median infarct volume was 1.8 mL, with most lesions confined to subcortical structures (61%) including the anterior choroidal artery territory (30%) and the pons (23%). Of ICARE participants, stroke patients, but they represent a clinically and scientifically important subgroup. Compared to lesions in general stroke populations and widely-studied animal models of recovery, ICARE participants had smaller, more subcortically-based strokes. Improved preclinical-clinical translational efforts may require better alignment of lesions between preclinical and human stroke recovery models. PMID:28337932

ERic Acute StrokE Recanalization: A study using predictive analytics to assess a new device for mechanical thrombectomy.

Science.gov (United States)

Siemonsen, Susanne; Forkert, Nils D; Bernhardt, Martina; Thomalla, Götz; Bendszus, Martin; Fiehler, Jens

2017-08-01

Aim and hypothesis Using a new study design, we investigate whether next-generation mechanical thrombectomy devices improve clinical outcomes in ischemic stroke patients. We hypothesize that this new methodology is superior to intravenous tissue plasminogen activator therapy alone. Methods and design ERic Acute StrokE Recanalization is an investigator-initiated prospective single-arm, multicenter, controlled, open label study to compare the safety and effectiveness of a new recanalization device and distal access catheter in acute ischemic stroke patients with symptoms attributable to acute ischemic stroke and vessel occlusion of the internal cerebral artery or middle cerebral artery. Study outcome The primary effectiveness endpoint is the volume of saved tissue. Volume of saved tissue is defined as difference of the actual infarct volume and the brain volume that is predicted to develop infarction by using an optimized high-level machine learning model that is trained on data from a historical cohort treated with IV tissue plasminogen activator. Sample size estimates Based on own preliminary data, 45 patients fulfilling all inclusion criteria need to complete the study to show an efficacy >38% with a power of 80% and a one-sided alpha error risk of 0.05 (based on a one sample t-test). Discussion ERic Acute StrokE Recanalization is the first prospective study in interventional stroke therapy to use predictive analytics as primary and secondary endpoint. Such trial design cannot replace randomized controlled trials with clinical endpoints. However, ERic Acute StrokE Recanalization could serve as an exemplary trial design for evaluating nonpivotal neurovascular interventions.

Relationship between Stroke Volume Variation and Blood Transfusion during Liver Transplantation.

Science.gov (United States)

Choi, Jae Moon; Lee, Yoon Kyung; Yoo, Hwanhee; Lee, Sukyung; Kim, Hee Yeong; Kim, Young-Kug

2016-01-01

Intraoperative blood transfusion increases the risk for perioperative mortality and morbidity in liver transplant recipients. A high stroke volume variation (SVV) method has been proposed to reduce blood loss during living donor hepatectomy. Herein, we investigated whether maintaining high SVV could reduce the need for blood transfusion and also evaluated the effect of the high SVV method on postoperative outcomes in liver transplant recipients. We retrospectively analyzed 332 patients who underwent liver transplantation, divided into control (maintaining blood transfusion requirement and hemodynamic parameters, including SVV, as well as postoperative outcomes, such as incidences of acute kidney injury, durations of postoperative intensive care unit and hospital stay, and rates of 1-year mortality. Mean SVV values were 7.0% ± 1.3% in the control group (n = 288) and 11.2% ± 1.8% in the high SVV group (n = 44). The median numbers of transfused packed red blood cells and fresh frozen plasmas in the high SVV group were significantly lower than those in control group (0 vs. 2 units, P = 0.003; and 0 vs. 3 units, P = 0.033, respectively). No significant between-group differences were observed for postoperative outcomes. Maintaining high SVV can reduce the blood transfusion requirement during liver transplantation without worsening postoperative outcomes. These findings provide insights into improving perioperative management in liver transplant recipients.

Atrophy of Swallowing Muscles Is Associated With Severity of Dysphagia and Age in Patients With Acute Stroke.

Science.gov (United States)

Sporns, Peter B; Muhle, Paul; Hanning, Uta; Suntrup-Krueger, Sonja; Schwindt, Wolfram; Eversmann, Julian; Warnecke, Tobias; Wirth, Rainer; Zimmer, Sebastian; Dziewas, Rainer

2017-07-01

Sarcopenia has been identified as an independent risk factor for dysphagia. Dysphagia is one of the most important and prognostically relevant complications of acute stroke. The role of muscle atrophy as a contributing factor for the occurrence of poststroke dysphagia is yet unclear. To assess whether there is a correlation between age and muscle volume and whether muscle volume is related to dysphagia in acute stroke patients. This retrospective, single-center study included 73 patients with acute ischemic or hemorrhagic stroke who underwent computed tomography angiography on admission and an objective dysphagia assessment by Fiberoptic Endoscopic Evaluation of Swallowing within 72 hours from admission. With the help of semiautomated muscle segmentation and 3-dimensional reconstruction volumetry of the digastric, temporal, and geniohyoid muscles was performed. For further analysis, participants were first divided into 4 groups according to their age (dysphagia severity using the Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS) (FEDSS 1 and 2, n = 25; FEDSS 3 and 4, n = 32; FEDSS 5 and 6, n = 16). Correlation of muscle volumes with age and dysphagia severity. Muscle volumes of single muscles (except for geniohyoid and the right digastric muscles) as well as the sum muscle volume were significantly and inversely related to dysphagia severity. We found a significant decline of muscle volume with advancing age for most muscle groups and, in particular, for the total muscle volume. Apart from features being determined by the acute stroke itself (eg, site and size of stroke), also premorbid conditions, in particular age-related muscle atrophy, have an impact on the complex pathophysiology of swallowing disorders poststroke. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Peri-operative troponin monitoring using a prototype high-sensitivity cardiac troponin I (hs-cTnI) assay: comparisons with hs-cTnT and contemporary cTnI assays.

LENUS (Irish Health Repository)

Lee, Graham R

2013-09-18

Non-cardiac surgery is associated with major vascular complications and higher incidences of elevated plasma troponin (cTn) concentration. Goal-directed therapy (GDT) is a stroke volume (SV)-guided approach to intravenous (IV) fluid therapy that improves tissue perfusion, oxygenation and reduces post-operative complications. In patients undergoing major gastro-intestinal surgery, we compared high sensitive and contemporary troponin assays and correlated results with patient outcome.

SV40-transformed human fibroblasts: evidence for cellular aging in pre-crisis cells.

Science.gov (United States)

Stein, G H

1985-10-01

Pre-crisis SV40-transformed human diploid fibroblast (HDF) cultures have a finite proliferative lifespan, but they do not enter a viable senescent state at end of lifespan. Little is known about either the mechanism for this finite lifespan in SV40-transformed HDF or its relationship to finite lifespan in normal HDF. Recently we proposed that in normal HDF the phenomena of finite lifespan and arrest in a viable senescent state depend on two separate processes: 1) an age-related decrease in the ability of the cells to recognize or respond to serum and/or other mitogens such that the cells become functionally mitogen-deprived at the end of lifespan; and 2) the ability of the cells to enter a viable, G1-arrested state whenever they experience mitogen deprivation. In this paper, data are presented that suggest that pre-crisis SV40-transformed HDF retain the first process described above, but lack the second process. It is shown that SV40-transformed HDF have a progressively decreasing ability to respond to serum as they age, but they continue to traverse the cell cycle at the end of lifespan. Concomitantly, the rate of cell death increases steadily toward the end of lifespan, thereby causing the total population to cease growing and ultimately to decline. Previous studies have shown that when SV40-transformed HDF are environmentally serum deprived, they likewise exhibit continued cell cycle traverse coupled with increased cell death. Thus, these results support the hypothesis that pre-crisis SV40-transformed HDF still undergo the same aging process as do normal HDF, but they end their lifespan in crisis rather than in the normal G1-arrested senescent state because they have lost their ability to enter a viable, G1-arrested state in response to mitogen deprivation.

Antička baština samostana sv. Frane u Splitu

OpenAIRE

Cambi, Nenad

2005-01-01

Na mjestu današnjega franjevačkog samostana sv. Frane u Splitu otkriveno je nekoliko starokršćanskih spomenika: dva natpisa (danas izgubljena), sarkofag s prikazom motiva Prelaska Izraelaca preko Crvenoga mora, fragment s prikazom Krista i apostola te najvjerojatnije i motivom Davida i Golijata, pilastar s urezanim križem, fragment akroterija sarkofaga s križem te omanji fragment pluteja s ljiljanom. Današnja crkva sv. Frane uništila je prethodni samostan i crkvu, koje je u XI. st. podigao sp...

Computed Tomography Perfusion Alberta Stroke Program Early Computed Tomography Score Is Associated with Hemorrhagic Transformation after Acute Cardioembolic Stroke

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Lan Liu

2017-11-01

Full Text Available Alberta Stroke Program Early Computed Tomography (CT score (ASPECTS has been applied to CT perfusion (CTP with good interrater agreement to predict early ischemic stroke, and it can be useful in decision making in acute ischemic stroke. The aim of the present study was to assess the predictive value of CTP ASPECTS of hemorrhagic transformation (HT in acute cardioembolic stroke. This is a single-enter, retrospective study. All patients hospitalized with acute cardioembolic stroke from January 2008 to September 2013 were included. ASPECTS of baseline non-contrast CT, CTP maps of cerebral blood volume (CBV, cerebral blood flow, and mean transit time were collected from 52 consecutive patients with less than 12-h anterior circulation ischemic stroke. MRI scan was performed within 72 h of symptom onset after index stroke including T2*-weighted gradient echo to identify HT. For bleeding risk assessment, CTP and diffusion-weighted imaging ASPECTS were categorized into 0–7 or 8–10. Baseline characteristics, ASPCETS scores and HT were compared. Eighteen (34.6% patients had HT and four (7.7% developed symptomatic HT. On univariate analysis, the proportion of patients with CBV-ASPECTS 0–7 was significantly higher in HT patients as compared to patients without HT (44 versus 9%, P = 0.005. CBV ASPECTS 0–7 remained independent prognostic factors for HT after adjustment for clinical baseline variables. CBV ASPECTS could be of value to predict HT risk after acute cardioembolic stroke and may be a quick risk assessment approach before reperfusion therapy.

Collateral vessels on magnetic resonance angiography in endovascular-treated acute ischemic stroke patients associated with clinical outcomes.

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Jiang, Liang; Su, Hao-Bo; Zhang, Ying-Dong; Zhou, Jun-Shan; Geng, Wen; Chen, Huiyou; Xu, Quan; Yin, Xindao; Chen, Yu-Chen

2017-10-06

Collateral vessels were considered to be related with outcome in endovascular-treated acute ischemic stroke patients. This study aimed to evaluate whether the collateral vessels on magnetic resonance angiography (MRA) could predict the clinical outcome. Acute stroke patients with internal carotid artery or middle cerebral artery occlusion within 6 hours of symptom onset were included. All patients underwent MRI and received endovascular treatment. The collateral circulations at the Sylvian fissure and the leptomeningeal convexity were evaluated. The preoperative and postoperative infarct volume was measured. The clinical outcome was evaluated by mRS score at 3 months after stroke. Of 55 patients, Cases with insufficient collateral circulation at the Sylvian fissure and leptomeningeal convexity showed that the NIHSS score at arrival and preoperative infarct volume were significantly lower in mRS score of 0-2 (both P collateral status at the leptomeningeal convexity were independent of the clinical outcome at 3 months after stroke (odds ratio (95% confidence interval): 1.094 (1.025-1.168); 9.542 (1.812-50.245) respectively). The change of infarct volume in the group with mRS score of 0-2 was smaller than that with mRS score of 3-6. While multivariate logistic models showed that postoperative infarct volume was non-significant in predicting the clinical outcome after stroke. The extent of collateral circulation at the leptomeningeal convexity may be useful for predicting the functional recovery while the relationship between postoperative infarct volume and clinical outcome still requires for further study.

Pre-existing hypertension dominates γδT cell reduction in human ischemic stroke.

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Mateusz G Adamski

Full Text Available T lymphocytes may play an important role in the evolution of ischemic stroke. Depletion of γδT cells has been found to abrogate ischemia reperfusion injury in murine stroke. However, the role of γδT cells in human ischemic stroke is unknown. We aimed to determine γδT cell counts and γδT cell interleukin 17A (IL-17A production in the clinical setting of ischemic stroke. We also aimed to determine the associations of γδT cell counts with ischemic lesion volume, measures of clinical severity and with major stroke risk factors. Peripheral blood samples from 43 acute ischemic stroke patients and 26 control subjects matched on race and gender were used for flow cytometry and complete blood count analyses. Subsequently, cytokine levels and gene expression were measured in γδT cells. The number of circulating γδT cells was decreased by almost 50% (p = 0.005 in the stroke patients. γδT cell counts did not correlate with lesion volume on magnetic resonance diffusion-weighted imaging or with clinical severity in the stroke patients, but γδT cells showed elevated levels of IL-17A (p = 0.048. Decreased γδT cell counts were also associated with older age (p = 0.004, pre-existing hypertension (p = 0.0005 and prevalent coronary artery disease (p = 0.03, with pre-existing hypertension being the most significant predictor of γδT cell counts in a multivariable analysis. γδT cells in human ischemic stroke are reduced in number and show elevated levels of IL-17A. A major reduction in γδT lymphocytes also occurs in hypertension and may contribute to the development of hypertension-mediated stroke and vascular disease.

The Influence of Acute Hyperglycemia in an Animal Model of Lacunar Stroke That Is Induced by Artificial Particle Embolization

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Tsai, Ming-Jun; Lin, Ming-Wei; Huang, Yaw-Bin; Kuo, Yu-Min; Tsai, Yi-Hung

2016-01-01

Animal and clinical studies have revealed that hyperglycemia during ischemic stroke increases the stroke's severity and the infarct size in clinical and animal studies. However, no conclusive evidence demonstrates that acute hyperglycemia worsens post-stroke outcomes and increases infarct size in lacunar stroke. In this study, we developed a rat model of lacunar stroke that was induced via the injection of artificial embolic particles during full consciousness. We then used this model to compare the acute influence of hyperglycemia in lacunar stroke and diffuse infarction, by evaluating neurologic behavior and the rate, size, and location of the infarction. The time course of the neurologic deficits was clearly recorded from immediately after induction to 24 h post-stroke in both types of stroke. We found that acute hyperglycemia aggravated the neurologic deficit in diffuse infarction at 24 h after stroke, and also aggravated the cerebral infarct. Furthermore, the infarct volumes of the basal ganglion, thalamus, hippocampus, and cerebellum but not the cortex were positively correlated with serum glucose levels. In contrast, acute hyperglycemia reduced the infarct volume and neurologic symptoms in lacunar stroke within 4 min after stroke induction, and this effect persisted for up to 24 h post-stroke. In conclusion, acute hyperglycemia aggravated the neurologic outcomes in diffuse infarction, although it significantly reduced the size of the cerebral infarct and improved the neurologic deficits in lacunar stroke. PMID:27226775

Neural correlates supporting sensory discrimination after left hemisphere stroke

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Borstad, Alexandra; Schmalbrock, Petra; Choi, Seongjin; Nichols-Larsen, Deborah S.

2012-01-01

Background Nearly half of stroke patients have impaired sensory discrimination, however, the neural structures that support post-stroke sensory function have not been described. Objectives 1) To evaluate the role of the primary somatosensory (S1) cortex in post-stroke sensory discrimination and 2) To determine the relationship between post-stroke sensory discrimination and structural integrity of the sensory component of the superior thalamic radiation (sSTR). Methods 10 healthy adults and 10 individuals with left hemisphere stroke participated. Stroke participants completed sensory discrimination testing. An fMRI was conducted during right, impaired hand sensory discrimination. Fractional anisotropy and volume of the sSTR were quantified using diffusion tensor tractography. Results Sensory discrimination was impaired in 60% of participants with left stroke. Peak activation in the left (S1) did not correlate with sensory discrimination ability, rather a more distributed pattern of activation was evident in post-stroke subjects with a positive correlation between peak activation in the parietal cortex and discrimination ability (r=.70, p=.023). The only brain region in which stroke participants had significantly different cortical activation than control participants was the precuneus. Region of interest analysis of the precuneus across stroke participants revealed a positive correlation between peak activation and sensory discrimination ability (r=.77, p=.008). The L/R ratio of sSTR fractional anisotropy also correlated with right hand sensory discrimination (r=.69, p=.027). Conclusions Precuneus cortex, distributed parietal lobe activity, and microstructure of the sSTR support sensory discrimination after left hemisphere stroke. PMID:22592076

Continuous monitoring of left ventricular function by VEST

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Ohtake, Tohru; Watanabe, Toshiaki; Kosaka, Noboru

1988-01-01

Using an ambulatory ventricular function monitor (VEST), left ventricular function (LVF) was examined in one healthy volunteer, 3 with ischemic heart disease, and one with dilated myocardiopathy (DMCP) under various conditions, such as treadmill exercise, standing, and sitting. It was also examined when two DCMP patients with associated left ventricular failure were given a nitrite (ISDM) and cardiotonic agent (E 1020). End-diastolic volume (EDV) decreased in the standing position, and increased in exercise, suggesting the involvement of venous blood pool in the legs. Ejection fraction (EF) decreased in the case of widespread ischemia during exercise. Drug tolerance test revealed decrease in EDV and end-systolic volume (ESV), no change in stroke volume (SV), and slight increase in EF on ISDM; and decrease in EDV and ESV, increase in SV, and marked increase in EF on E 1020. For EF, the VEST data were relatively well correlated with gamma camera data. (Namekawa, K.)

Radionuclide angiocardiography in the normal dog: first-pass studies

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Brom, W.E. van den; Stokhof, A.A. (Utrecht Univ. (Netherlands). Dept. of Clinical Sciences of Companion Animals)

1989-11-01

The first pass of a bolus of radioactivity ({sup 99m}Tc) through the heart and lungs was studied in 27 anaesthetised healthy adult mongrel dogs, using a gamma camera with a computer on-line. Bodyweights ranged from 9 to 60 kg, heart rate from 108 to 150 beats min{sup -1}. Quantitative analysis revealed that the distribution volume (DV) of the labelled blood, the cardiac output (CO), the stroke volume (SV) and pulmonary blood volume (PBV) were almost proportional to the bodyweight. Specific results were: DV 120 ml kg{sup -1}, CO 136 ml kg{sup -1}, SV 1.11 ml kg{sup -1}, PBV 6.9 ml kg{sup -1}. The pulmonary transit time varied between 1.0 and 3.6 seconds. Clinical applicability of the method, including visual inspection of camera images and quantitative analysis of a time-activity curve of the lung, was demonstrated for one dog with an aortic stenosis and another with a left-to-right shunt. (author).

Validity and reliability of the Brazilian version of Yale-Brown obsessive compulsive scale-shopping version (YBOCS-SV).

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Leite, Priscilla Lourenço; Filomensky, Tatiana Zambrano; Black, Donald W; Silva, Adriana Cardoso

2014-08-01

The Yale-Brown Obsessive Compulsive Scale-Shopping Version (YBOCS-SV) is considered the gold standard in the assessment of shopping severity. It is designed to assess cognitions and behaviors relating to compulsive buying behavior. The present study aims to assess the validity of the Brazilian version of this scale. For the study, composed the sample 610 participants: 588 subjects of a general population and 22 compulsive buyers. Factorial analysis was performed to assess the relations and the correlation between the YBOCS-SV, the Compulsive Buying Scale (CBS), and Richmond Compulsive Buying Scale (RCBS), was assessed using Pearson coefficient, for study of convergent and divergent validity. Cronbach's alpha coefficients were used to assess internal consistency. The results show good to excellent psychometric parameters for the YBOCS-SV in its Brazilian version. With regard to correlations, the YBOCS-SV is inversely and proportionally correlated with CBS and the RCBS, indicating that the YBOCS-SV is an excellent instrument for screening compulsive buying. The YBOCS-SV presented high alpha coefficient of Cronbach's alpha (0.92), demonstrating good reliability. The Brazilian version of the YBOCS-SV is indicated to diagnose compulsive buying disorder, and likely use for the purposes intended in the Brazilian population. Copyright © 2014 Elsevier Inc. All rights reserved.

Analysis of plasma membrane Ca(2+)-ATPase expression in control and SV40-transformed human fibroblasts.

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Reisner, P D; Brandt, P C; Vanaman, T C

1997-01-01

It has been long known that neoplastic transformation is accompanied by a lowered requirement for extracellular Ca2+ for growth. The studies presented here demonstrate that human fibroblastic cell lines produce the two commonly found 'housekeeping' isoforms of the plasma membrane Ca(2+)-ATPase (PMCA), PMCA1b and 4b, and at the expression of both is demonstrably lower in cell lines neoplastically transformed by SV40 than in the corresponding parental cell lines. Western blot analyses of lysates from control (GM00037) and SV40-transformed (GM00637) skin fibroblasts revealed a 138 kDa PMCA whose level was significantly lower in the SV40-transformed cells relative to either total cellular protein or alpha-tubulin. Similar analyses of plasma membrane preparations from control WI-38) and SV40-transformed (WI-38VA13) lung fibroblasts revealed 3-4-fold lower levels of PMCA in the SV40-transformed cells. Competitive ELISAs performed on detergent solubilized plasma membrane preparations indicated at least 3-4-fold lower levels of PMCA in the SV40-transformed cell lines compared to controls. Reverse transcriptase coupled-PCR analyses showed that PMCA1b and PMCA4b were the only isoforms expressed in all four cell lines. The PMCA4b mRNA level detected by Northern analysis also was substantially lower in SV40 transformed skin fibroblasts than in non-transformed fibroblasts. Quantitative RT-PCR analyses showed levels of PMCA1b and 4b mRNAs to be 5 and 10-fold lower, respectively, in GM00637 than in GM00037 when the levels of PCR products were normalized to glyceraldehyde-3-phosphate dehydrogenase (G3PDH) mRNA. These results demonstrate that the expression of these distinct PMCA genes is substantially lower in SV40 transformed human skin and lung fibroblasts and may be coordinately regulated in these cells.

Correlating lesion size and location to deficits after ischemic stroke: the influence of accounting for altered peri-necrotic tissue and incidental silent infarcts

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Black Sandra E

2010-01-01

Full Text Available Abstract Background Investigators frequently quantify and evaluate the location and size of stroke lesions to help uncover cerebral anatomical correlates of deficits observed after first-ever stroke. However, it is common to discover silent infarcts such as lacunes in patients identified clinically as 'first-ever' stroke, and it is unclear if including these incidental findings may impact lesion-based investigations of brain-behaviour relationships. There is also debate concerning how to best define the boundaries of necrotic stroke lesions that blend in an ill-defined way into surrounding tissue, as it is unclear whether including this altered peri-necrotic tissue region may influence studies of brain-behaviour relationships. Therefore, for patients with clinically overt stroke, we examined whether including altered peri-necrotic tissue and incidental silent strokes influenced either lesion volume correlations with a measure of sensorimotor impairment or the anatomical localization of this impairment established using subtraction lesion analysis. Methods Chronic stroke lesions of 41 patients were manually traced from digital T1-MRI to sequentially include the: necrotic lesion core, altered peri-necrotic tissue, silent lesions in the same hemisphere as the index lesion, and silent lesions in the opposite hemisphere. Lesion volumes for each region were examined for correlation with motor impairment scores, and subtraction analysis was used to highlight anatomical lesion loci associated with this deficit. Results For subtraction lesion analysis, including peri-necrotic tissue resulted in a larger region of more frequent damage being seen in the basal ganglia. For correlational analysis, only the volume of the lesion core was significantly associated with motor impairment scores (r = -0.35, p = 0.025. In a sub-analysis of patients with small subcortical index lesions, adding silent lesions in the opposite hemisphere to the volume of the index

Dynamic VaR Measurement of Gold Market with SV-T-MN Model

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Fenglan Li

2017-01-01

Full Text Available VaR (Value at Risk in the gold market was measured and predicted by combining stochastic volatility (SV model with extreme value theory. Firstly, for the fat tail and volatility persistence characteristics in gold market return series, the gold price return volatility was modeled by SV-T-MN (SV-T with Mixture-of-Normal distribution model based on state space. Secondly, future sample volatility prediction was realized by using approximate filtering algorithm. Finally, extreme value theory based on generalized Pareto distribution was applied to measure dynamic risk value (VaR of gold market return. Through the proposed model on the price of gold, empirical analysis was investigated; the results show that presented combined model can measure and predict Value at Risk of the gold market reasonably and effectively and enable investors to further understand the extreme risk of gold market and take coping strategies actively.

Functional significance of ipsilesional motor deficits after unilateral stroke.

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Chestnut, Caitilin; Haaland, Kathleen Y

2008-01-01

To determine whether ipsilesional motor skills, which have been related to independent functioning, are present chronically after unilateral stroke and are more common in people with apraxia than in those without apraxia. Observational cohort comparing the performance of an able-bodied control group, stroke patients with left- or right-hemisphere damage matched for lesion volume, and left-hemisphere stroke patients with and without ideomotor limb apraxia. Primary care Veterans Affairs and private medical center. Volunteer right-handed sample; stroke patients with left- or right-hemisphere damage about 4 years poststroke; a control group of demographically matched, able-bodied adults. Not applicable. Total time to perform the (1) Williams doors test and the (2) timed manual performance test (TMPT), which includes parts of the Jebsen-Taylor Hand Function Test. Ipsilesional motor deficits were present after left- or right-hemisphere stroke when using both measures, but deficits were consistently more common in patients with limb apraxia only for the TMPT. These findings add to a growing literature that suggests that ipsilesional motor deficits may have a functional impact in unilateral stroke patients, especially in patients with ideomotor limb apraxia.

mStroke: "Mobile Stroke"-Improving Acute Stroke Care with Smartphone Technology.

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Andrew, Benjamin Y; Stack, Colleen M; Yang, Julian P; Dodds, Jodi A

2017-07-01

This study aimed to evaluate the effect of method and time of system activation on clinical metrics in cases utilizing the Stop Stroke (Pulsara, Inc.) mobile acute stroke care coordination application. A retrospective cohort analysis of stroke codes at 12 medical centers using Stop Stroke from March 2013 to May 2016 was performed. Comparison of metrics (door-to-needle time [DTN] and door-to-CT time [DTC], and rate of DTN ≤ 60 minutes [goal DTN]) was performed between subgroups based on method (emergency medical service [EMS] versus emergency department [ED]) and time of activation. Effects were adjusted for confounders (age, sex, National Institutes of Health Stroke Scale [NIHSS] score) using multiple linear and logistic regression. The final dataset included 2589 cases. Cases activated by EMS were more severe (median NIHSS score 8 versus 4, P technology provides unique insight into acute stroke codes. Activation of mobile electronic stroke coordination in the field appears to promote a more expedited and successful care process. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

MR-based cerebral blood volume maps as a diagnostic tool of stroke: results of a clinical pilot study

International Nuclear Information System (INIS)

Hacklaender, T.; Hofer, M.; Binkofski, F.; Reichenbach, J.; Moedder, U.

1996-01-01

In this study the sensitivity of proving a stroke using regional cerebral blood volume (rCBV) maps were investigated. Another aim was to evaluate the strength of the ischaemia. Seven patients were examined during the acute phase of a stroke, eight during the subacute or chronically stage. To calculate rCBV-maps of one slice low dosed Gd-DTPA was injected as a bolus. Using the relaxation-effect the obtained signal intensity-time curves were converted pixel-wise to rCBV images. For the region of the infarction rCBV ratios were calculated relative to the corresponding area in the contralateral hemisphere. Only 63% of the investigations carried out during the acute phase were utilizable. In all those cases a decrease of rCBV was found. The infarct area could only be visually recognized if the rCBV ratio was lower than 0.7. The ratios of completely and partical necrotic areas of the infarctions were 0.481 and 1.028 respectively. With a p=0.0015 these values are even statistically different. During the acute stage the sensitivity of the rCBV measurement was not as high as that of morphological MR imaging. However, rCBV maps make it possible to estimate the strength of the ischaemia even during the first hours. (orig./MG) [de

Left ventricular function during acute high-altitude exposure in a large group of healthy young Chinese men.

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Mingyue Rao

Full Text Available The purpose of this study was to observe left ventricular function during acute high-altitude exposure in a large group of healthy young males.A prospective trial was conducted in Szechwan and Tibet from June to August, 2012. By Doppler echocardiography, left ventricular function was examined in 139 healthy young Chinese men at sea level; within 24 hours after arrival in Lhasa, Tibet, at 3700 m; and on day 7 following an ascent to Yangbajing at 4400 m after 7 days of acclimatization at 3700 m. The resting oxygen saturation (SaO2, heart rate (HR and blood pressure (BP were also measured at the above mentioned three time points.Within 24 hours of arrival at 3700 m, the HR, ejection fraction (EF, fractional shortening (FS, stroke volume (SV, cardiac output (CO, and left ventricular (LV Tei index were significantly increased, but the LV end-systolic dimension (ESD, end-systolic volume (ESV, SaO2, E/A ratio, and ejection time (ET were significantly decreased compared to the baseline levels in all subjects. On day 7 at 4400 m, the SV and CO were significantly decreased; the EF and FS Tei were not decreased compared with the values at 3700 m; the HR was further elevated; and the SaO2, ESV, ESD, and ET were further reduced. Additionally, the E/A ratio was significantly increased on day 7 but was still lower than it was at low altitude.Upon acute high-altitude exposure, left ventricular systolic function was elevated with increased stroke volume, but diastolic function was decreased in healthy young males. With higher altitude exposure and prolonged acclimatization, the left ventricular systolic function was preserved with reduced stroke volume and improved diastolic function.

Variation of clinical target volume definition in three-dimensional conformal radiation therapy for prostate cancer

International Nuclear Information System (INIS)

Valicenti, Richard K.; Sweet, John W.; Hauck, Walter W.; Hudes, Richard S.; Lee, Tony; Dicker, Adam P.; Waterman, Frank M.; Anne, Pramila R.; Corn, Benjamin W.; Galvin, James M.

1999-01-01

Purpose: Currently, three-dimensional conformal radiation therapy (3D-CRT) planning relies on the interpretation of computed tomography (CT) axial images for defining the clinical target volume (CTV). This study investigates the variation among multiple observers to define the CTV used in 3D-CRT for prostate cancer. Methods and Materials: Seven observers independently delineated the CTVs (prostate ± seminal vesicles [SV]) from the CT simulation data of 10 prostate cancer patients undergoing 3D-CRT. Six patients underwent CT simulation without the use of contrast material and serve as a control group. The other 4 had urethral and bladder opacification with contrast medium. To determine interobserver variation, we evaluated the derived volume, the maximum dimensions, and the isocenter for each examination of CTV. We assessed the reliability in the CTVs among the observers by correlating the variation for each class of measurements. This was estimated by intraclass correlation coefficient (ICC), with 1.00 defining absolute correlation. Results: For the prostate volumes, the ICC was 0.80 (95% confidence interval [CI]: 0.56-0.96). This changed to 0.92 (95% CI: 0.75-0.99) with the use of contrast material. Similarly, the maximal prostatic dimensions were reliable and improved. There was poor agreement in defining the SV. For this structure, the ICC never exceeded 0.28. The reliability of the isocenter was excellent, with the ICC exceeding 0.83 and 0.90 for the prostate ± SV, respectively. Conclusions: In 3D-CRT for prostate cancer, there was excellent agreement among multiple observers to define the prostate target volume but poor agreement to define the SV. The use of urethral and bladder contrast improved the reliability of localizing the prostate. For all CTVs, the isocenter was very reliable and should be used to compare the variation in 3D dosimetry among multiple observers

Value of Quantitative Collateral Scoring on CT Angiography in Patients with Acute Ischemic Stroke.

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Boers, A M M; Sales Barros, R; Jansen, I G H; Berkhemer, O A; Beenen, L F M; Menon, B K; Dippel, D W J; van der Lugt, A; van Zwam, W H; Roos, Y B W E M; van Oostenbrugge, R J; Slump, C H; Majoie, C B L M; Marquering, H A

2018-06-01

Many studies have emphasized the relevance of collateral flow in patients presenting with acute ischemic stroke. Our aim was to evaluate the relationship of the quantitative collateral score on baseline CTA with the outcome of patients with acute ischemic stroke and test whether the timing of the CTA acquisition influences this relationship. From the Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN) data base, all baseline thin-slice CTA images of patients with acute ischemic stroke with intracranial large-vessel occlusion were retrospectively collected. The quantitative collateral score was calculated as the ratio of the vascular appearance of both hemispheres and was compared with the visual collateral score. Primary outcomes were 90-day mRS score and follow-up infarct volume. The relation with outcome and the association with treatment effect were estimated. The influence of the CTA acquisition phase on the relation of collateral scores with outcome was determined. A total of 442 patients were included. The quantitative collateral score strongly correlated with the visual collateral score (ρ = 0.75) and was an independent predictor of mRS (adjusted odds ratio = 0.81; 95% CI, .77-.86) and follow-up infarct volume (exponent β = 0.88; P quantitative collateral score showed areas under the curve of 0.71 and 0.69 for predicting functional independence (mRS 0-2) and follow-up infarct volume of >90 mL, respectively. We found significant interaction of the quantitative collateral score with the endovascular therapy effect in unadjusted analysis on the full ordinal mRS scale ( P = .048) and on functional independence ( P = .049). Modification of the quantitative collateral score by acquisition phase on outcome was significant (mRS: P = .004; follow-up infarct volume: P quantitative collateral scoring in patients with acute ischemic stroke is a reliable and user-independent measure of the collateral

Evolutionary models of early-type contact binary SV Centauri

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Nakamura, Y; Saio, H [Tohoku Univ., Sendai (Japan). Faculty of Science; Sugimoto, Daiichiro

1978-12-01

Models of the early-type contact binary system SV Centauri are computed with a binary-star evolution program. The effects of mass exchange, i.e., the effects of mass acceptance as well as mass loss, are properly included. With the initial masses of the component stars as 12.4 and 8.0 M sub(solar mass), the following observed configurations are well reproduced; the component stars are definitely in contact and the rate of mass exchange is 4 x 10/sup -4/ M sub(solar mass)yr/sup -1/. The more massive component is less luminous and has a lower effective temperature. Such features are also reproduced quantitatively. Agreement of the computed models with observation indicates that the binary system SV Cen is actually in the phase of rapid mass exchange preceding the mass-ratio reversal.

Characterization of SV-40 Tag rats as a model to study prostate cancer

International Nuclear Information System (INIS)

Harper, Curt E; Patel, Brijesh B; Cook, Leah M; Wang, Jun; Shirai, Tomoyuki; Eltoum, Isam A; Lamartiniere, Coral A

2009-01-01

Prostate cancer is the second most frequently diagnosed cancer in men. Animal models that closely mimic clinical disease in humans are invaluable tools in the fight against prostate cancer. Recently, a Simian Virus-40 T-antigen (SV-40 Tag) targeted probasin promoter rat model was developed. This model, however, has not been extensively characterized; hence we have investigated the ontogeny of prostate cancer and determined the role of sex steroid receptor and insulin-like growth factor-1 (IGF-1) signaling proteins in the novel SV-40 Tag rat. The SV-40 Tag rat was histopathologically characterized for time to tumor development, incidence and multiplicity and in the ventral, dorsal, lateral and anterior lobes of the prostate. Immunoassay techniques were employed to measure cell proliferation, apoptosis, and sex steroid receptor and growth factor signaling-related proteins. Steroid hormone concentrations were measured via coated well enzyme linked immunosorbent assay (ELISA) kits. Prostatic intraepithelial neoplasia (PIN) and well-differentiated prostate cancer developed as early as 2 and 10 weeks of age, respectively in the ventral prostate (VP) followed by in the dorsolateral (DLP). At 8 weeks of age, testosterone and dihydrotestosterone (DHT) concentrations in SV-40 Tag rats were increased when compared to non-transgenic rats. High cell proliferation and apoptotic indices were found in VP and DLP of transgenic rats. Furthermore, we observed increased protein expression of androgen receptor, IGF-1, IGF-1 receptor, and extracellular signal-regulated kinases in the prostates of SV-40 Tag rats. The rapid development of PIN and prostate cancer in conjunction with the large prostate size makes the SV-40 Tag rat a useful model for studying prostate cancer. This study provides evidence of the role of sex steroid and growth factor proteins in prostate cancer development and defines appropriate windows of opportunity for preclinical trials and aids in the rational design of

Measurement of right ventricular volumes using 131I-MAA

International Nuclear Information System (INIS)

Sekimoto, T.; Grover, R.F.

1975-01-01

A method is presented for determining the right ventricular residual ratio, that is, the ratio of the end-systolic volume to the end-diastolic volume during each cardiac cycle. 131 I-MAA was injected as a bolus into the right ventricle, and the ratio of isotope remaining in the chamber during the succeeding cardiac cycles was determined with a collimated scintillation counter placed over the right ventricle. Since the counter detected the radioactivity from the entire right ventricular cavity, potential errors from incomplete mixing were minimized. The washout curve from the ventricle was distorted somewhat by the accumulation of isotope in intervening lung tissue. This distortion was eliminated by subtracting the build-up curve of radioactivity in the lung recorded simultaneously with a second scintillation counter positioned over the lateral chest wall. In 14 dogs anesthetized with chloralose, the right ventricular residual ratio was relatively constant at 40.4 +- 3.1 per cent. Duplicate measurements differed by less than 3 percent indicating the good reproducibility of the method. Right ventricular stroke volume was determined from cardiac output (dye dilution) and heart rate. With this and the simultaneously determined residual ratio ( 131 I-MAA), end-diastolic volume could be calculated. Stroke volume and stroke work were highly correlated with end-diastolic volume, in keeping with the Frank-Starling mechanism. (U.S.)

Pediatric Stroke

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... and Patient Resources Home » Patients & Families » About Stroke » Pediatric Stroke » Introduction Introduction What is a Stroke? Ischemic Stroke Intracerebral Hemorrhage Subarachnoid Hemorrhage Pediatric Stroke Introduction Types of Stroke Diagnosis and Treatment ...

Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants

International Nuclear Information System (INIS)

Kawano, Masaaki; Morikawa, Katsuma; Suda, Tatsuya; Ohno, Naohito; Matsushita, Sho; Akatsuka, Toshitaka; Handa, Hiroshi; Matsui, Masanori

2014-01-01

Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A ⁎ 02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A ⁎ 02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. - Highlights: • We constructed chimeric SV40-VLPs carrying an influenza virus-derived CTL epitope. • Chimeric SV40-VLPs induce influenza-specific CTLs in mice without adjuvants. • Chimeric SV40-VLPs induce heterosubtypic protection against influenza A viruses. • Chimeric SV40-VLPs induce long-lasting memory CTLs. • Chimeric SV40-VLPs is a promising vaccine platform with self-adjuvant properties

Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants

Energy Technology Data Exchange (ETDEWEB)

Kawano, Masaaki [Department of Allergy and Immunology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Morikawa, Katsuma [Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501 (Japan); Suda, Tatsuya [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Laboratory for Immunopharmacology of Microbial Products, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Ohno, Naohito [Laboratory for Immunopharmacology of Microbial Products, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Matsushita, Sho [Department of Allergy and Immunology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Allergy Center, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Akatsuka, Toshitaka [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan); Handa, Hiroshi, E-mail: handa.h.aa@m.titech.ac.jp [Solutions Research Laboratory, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8503 (Japan); Matsui, Masanori, E-mail: mmatsui@saitama-med.ac.jp [Department of Microbiology, Faculty of Medicine, Saitama Medical University, Moroyama-cho, Iruma-gun, Saitama 350-0495 (Japan)

2014-01-05

Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A{sup ⁎}02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A{sup ⁎}02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. - Highlights: • We constructed chimeric SV40-VLPs carrying an influenza virus-derived CTL epitope. • Chimeric SV40-VLPs induce influenza-specific CTLs in mice without adjuvants. • Chimeric SV40-VLPs induce heterosubtypic protection against influenza A viruses. • Chimeric SV40-VLPs induce long-lasting memory CTLs. • Chimeric SV40-VLPs is a promising vaccine platform with self-adjuvant properties.

Ischemic stroke destabilizes circadian rhythms

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Borjigin Jimo

2008-10-01

Full Text Available Abstract Background The central circadian pacemaker is a remarkably robust regulator of daily rhythmic variations of cardiovascular, endocrine, and neural physiology. Environmental lighting conditions are powerful modulators of circadian rhythms, but regulation of circadian rhythms by disease states is less clear. Here, we examine the effect of ischemic stroke on circadian rhythms in rats using high-resolution pineal microdialysis. Methods Rats were housed in LD 12:12 h conditions and monitored by pineal microdialysis to determine baseline melatonin timing profiles. After demonstration that the circadian expression of melatonin was at steady state, rats were subjected to experimental stroke using two-hour intralumenal filament occlusion of the middle cerebral artery. The animals were returned to their cages, and melatonin monitoring was resumed. The timing of onset, offset, and duration of melatonin secretion were calculated before and after stroke to determine changes in circadian rhythms of melatonin secretion. At the end of the monitoring period, brains were analyzed to determine infarct volume. Results Rats demonstrated immediate shifts in melatonin timing after stroke. We observed a broad range of perturbations in melatonin timing in subsequent days, with rats exhibiting onset/offset patterns which included: advance/advance, advance/delay, delay/advance, and delay/delay. Melatonin rhythms displayed prolonged instability several days after stroke, with a majority of rats showing a day-to-day alternation between advance and delay in melatonin onset and duration. Duration of melatonin secretion changed in response to stroke, and this change was strongly determined by the shift in melatonin onset time. There was no correlation between infarct size and the direction or amplitude of melatonin phase shifting. Conclusion This is the first demonstration that stroke induces immediate changes in the timing of pineal melatonin secretion, indicating

Bone marrow stromal cell therapy for ischemic stroke: A meta-analysis of randomized control animal trials.

Science.gov (United States)

Wu, Qing; Wang, Yuexiang; Demaerschalk, Bart M; Ghimire, Saruna; Wellik, Kay E; Qu, Wenchun

2017-04-01

Background Results of animal studies assessing efficacy of bone marrow stromal cell therapy for ischemic stroke remain inconsistent. Aims The aims are to assess efficacy of bone marrow stromal cell therapy for ischemic stroke in animal studies. Methods Randomized controlled animal trials assessing efficacy of bone marrow stromal cell therapy were eligible. Stroke therapy academic industry round table was used to assess methodologic quality of included studies. Primary outcomes were total infarction volume and modified Neurological Severity Score. Multiple prespecified sensitivity analyses and subgroup analyses were conducted. Random effects models were used for meta-analysis. Results Thirty-three randomized animal trials were included with a total of 796 animals. The median quality score was 6 (interquartile range, 5-7). Bone marrow stromal cell therapy decreased total infarction volume (standardized mean difference, 0.897; 95% confidence interval, 0.553-1.241; P animals treated with bone marrow stromal cell and controls was 2.47 (95% confidence interval, 1.84-3.11; P animal studies. Conclusions Bone marrow stromal cell therapy significantly decreased total infarction volume and increased neural functional recovery in randomized controlled animal models of ischemic stroke.

Middle cerebral artery occlusion in Macaca fascicularis: acute and chronic stroke evolution.

Science.gov (United States)

D'Arceuil, Helen E; Duggan, Michael; He, Julian; Pryor, Johnny; de Crespigny, Alex

2006-04-01

An intravascular stroke model designed for magnetic resonance imaging was developed in Macaca fascicularis (M. fascicularis) to characterize serial stroke lesion evolution. This model produces a range of stroke lesion sizes which closely mimics human stroke evolution. This paper describes the care of animals undergoing this stroke procedure, the range of outcomes we experienced and the cause of mortality in this model. Anesthesia was induced with atropine and ketamine and maintained with isoflurane or propofol. Non-invasive blood pressure, oxygen saturation, heart rate, respiration rate, temperature and end tidal CO2 were monitored continuously. The stroke was created by occluding a distal branch of the middle cerebral artery. During catheter placement animals were heparinized and vasospasm was minimized using verapamil. Anesthetic induction and maintenance were smooth. Animals with small strokes showed very rapid recovery, were able to ambulate and self-feed within 2 hours of recovery. Animals with strokes of >or=4% of the hemispheric volume required lengthy observation during recovery and parenteral nutrition. Large strokes resulted in significant brain edema, herniation and brainstem compression. Intracerebral hemorrhage and or subarachnoid hemorrhage coupled with a stroke of any size was acutely fatal. In the absence of an effective acute stroke therapy, the spectrum of outcomes seen in our primate model is very similar to that observed in human stroke patients.

Stroke mimic diagnoses presenting to a hyperacute stroke unit.

Science.gov (United States)

Dawson, Ang; Cloud, Geoffrey C; Pereira, Anthony C; Moynihan, Barry J

2016-10-01

Stroke services have been centralised in several countries in recent years. Diagnosing acute stroke is challenging and a high proportion of patients admitted to stroke units are diagnosed as a non-stroke condition (stroke mimics). This study aims to describe the stroke mimic patient group, including their impact on stroke services. We analysed routine clinical data from 2,305 consecutive admissions to a stroke unit at St George's Hospital, London. Mimic groupings were derived from 335 individual codes into 17 groupings. From 2,305 admissions, 555 stroke mimic diagnoses were identified (24.2%) and 72% of stroke mimics had at least one stroke risk factor. Common mimic diagnoses were headache, seizure and syncope. Medically unexplained symptoms and decompensation of underlying conditions were also common. Median length of stay was 1 day; a diagnosis of dementia (p=0.028) or needing MRI (p=0.006) was associated with a longer stay. Despite emergency department assessment by specialist clinicians and computed tomography brain, one in four suspected stroke patients admitted to hospital had a non-stroke diagnosis. Stroke mimics represent a heterogeneous patient group with significant impacts on stroke services. Co-location of stroke and acute neurology services may offer advantages where service reorganisation is being considered. © Royal College of Physicians 2016. All rights reserved.

Lesion segmentation from multimodal MRI using random forest following ischemic stroke.

Science.gov (United States)

Mitra, Jhimli; Bourgeat, Pierrick; Fripp, Jurgen; Ghose, Soumya; Rose, Stephen; Salvado, Olivier; Connelly, Alan; Campbell, Bruce; Palmer, Susan; Sharma, Gagan; Christensen, Soren; Carey, Leeanne

2014-09-01

Understanding structure-function relationships in the brain after stroke is reliant not only on the accurate anatomical delineation of the focal ischemic lesion, but also on previous infarcts, remote changes and the presence of white matter hyperintensities. The robust definition of primary stroke boundaries and secondary brain lesions will have significant impact on investigation of brain-behavior relationships and lesion volume correlations with clinical measures after stroke. Here we present an automated approach to identify chronic ischemic infarcts in addition to other white matter pathologies, that may be used to aid the development of post-stroke management strategies. Our approach uses Bayesian-Markov Random Field (MRF) classification to segment probable lesion volumes present on fluid attenuated inversion recovery (FLAIR) MRI. Thereafter, a random forest classification of the information from multimodal (T1-weighted, T2-weighted, FLAIR, and apparent diffusion coefficient (ADC)) MRI images and other context-aware features (within the probable lesion areas) was used to extract areas with high likelihood of being classified as lesions. The final segmentation of the lesion was obtained by thresholding the random forest probabilistic maps. The accuracy of the automated lesion delineation method was assessed in a total of 36 patients (24 male, 12 female, mean age: 64.57±14.23yrs) at 3months after stroke onset and compared with manually segmented lesion volumes by an expert. Accuracy assessment of the automated lesion identification method was performed using the commonly used evaluation metrics. The mean sensitivity of segmentation was measured to be 0.53±0.13 with a mean positive predictive value of 0.75±0.18. The mean lesion volume difference was observed to be 32.32%±21.643% with a high Pearson's correlation of r=0.76 (p<0.0001). The lesion overlap accuracy was measured in terms of Dice similarity coefficient with a mean of 0.60±0.12, while the contour

Splenectomy Does Not Improve Long-Term Outcome After Stroke.

Science.gov (United States)

Zierath, Dannielle; Shen, Angela; Stults, Astiana; Olmstead, Theresa; Becker, Kyra J

2017-02-01

Immune responses to brain antigens after stroke contribute to poor outcome. We hypothesized that splenectomy would lessen the development of such responses and improve outcome. Male Lewis rats (275-350 g) underwent 2-hour middle cerebral artery occlusion immediately after splenectomy or sham splenectomy. Animals were survived to 4 weeks (672 hrs), and immune responses to myelin basic protein determined at euthanasia. Infarct volume was determined in a subset of animals euthanized at 72 hours. Behavioral outcomes were assessed to 672 hours. Splenectomy was associated with worse neurological scores early after stroke, but infarct size at 72 hours was similar in both groups. Behavioral outcomes and immune responses to myelin basic protein were also similar among splenectomized and sham-operated animals 672 hours after middle cerebral artery occlusion. Splenectomy did not alter the immune responses to brain antigens or improve outcome after stroke. Differences between this study and other studies of splenectomy and stroke are examined. © 2017 American Heart Association, Inc.

A mouse model for chronic lymphocytic leukemia based on expression of the SV40 large T antigen

DEFF Research Database (Denmark)

ter Brugge, Petra J; Ta, Van B T; de Bruijn, Marjolein J W

2009-01-01

The simian virus 40 (SV40) T antigen is a potent oncogene able to transform many cell types and has been implicated in leukemia and lymphoma. In this report, we have achieved sporadic SV40 T-antigen expression in mature B cells in mice, by insertion of a SV40 T antigen gene in opposite...... transcriptional orientation in the immunoglobulin (Ig) heavy (H) chain locus between the D and J(H) segments. SV40 T-antigen expression appeared to result from retention of the targeted germline allele and concomitant antisense transcription of SV40 large T in mature B cells, leading to chronic lymphocytic...... leukemia (CLL). Although B-cell development was unperturbed in young mice, aging mice showed accumulation of a monoclonal B-cell population in which the targeted IgH allele was in germline configuration and the wild-type IgH allele had a productive V(D)J recombination. These leukemic B cells were Ig...

Difficulty of MRI based identification of lesion age by acute infra-tentorial ischemic stroke.

Directory of Open Access Journals (Sweden)

Florian Grosse-Dresselhaus

Full Text Available Systemic thrombolysis in acute ischemic stroke is restricted to the 4.5 h time window. Many patients are excluded from this treatment because symptom onset is unknown. Magnetic resonance imaging (MRI studies have shown that stroke patients presenting with acute supra-tentorial diffusion-weighted imaging (DWI lesions that do not have matching lesions on fluid attenuated inversion recovery (FLAIR are likely to be within a 4.5 hour time window. This study examines the DWI-FLAIR mismatch in infra-tentorial stroke.This was a retrospectively conducted substudy of the "1000+" study; a prospective, single-center observational study (http://clinicaltrials.gov; NCT00715533. Fifty-six patients with infra-tentorial stroke confirmed by MRI and known symptom onset who underwent the scan within 24 h after symptom onset were analysed. Two neurologists blinded to clinical information separately rated the DWI lesion visibility on FLAIR. Lesion volume, relative signal intensities of DWI and relative apparent diffusion coefficient values were determined.Regarding baseline characteristics our study population had a median age of 66 years, a median time from symptom onset to MRI of 616.5 minutes, a median NIHSS of 3 and a median DWI lesion volume of 0.26 ml. A negative FLAIR allocated patients to a time window under 4.5 h correctly with a sensitivity of 55% and a specificity of 61%, a positive predictive value of 44% and a negative predictive value of 71%. FLAIR positivity decreased with age (p = 0.018, and showed no significant correlation to lesion volume (p = 0.145.In our study the DWI-FLAIR-Mismatch does not help to reliably identify patients within 4.5 h of symptom onset in acute ischemic infra-tentorial stroke. Thus therapeutical decisions based on the DWI-FLAIR mismatch estimation of time from onset cannot be recommended in patients with infra-tentorial stroke.

A monoclonal antibody against SV40 large T antigen (PAb416) does not label Merkel cell carcinoma.

Science.gov (United States)

Pelletier, Daniel J; Czeczok, Thomas W; Bellizzi, Andrew M

2018-07-01

Merkel cell carcinoma represents poorly differentiated neuroendocrine carcinoma of cutaneous origin. In most studies, the vast majority of Merkel cell carcinomas are Merkel cell polyomavirus (MCPyV)-associated. SV40 polyomavirus immunohistochemistry is typically used in the diagnosis of other polyomavirus-associated diseases, including tubulointerstitial nephritis and progressive multifocal leukoencephalopathy, given cross-reactivity with BK and JC polyomaviruses. MCPyV-specific immunohistochemistry is commercially available, but, if antibodies against SV40 also cross-reacted with MCPyV, that would be advantageous from a resource-utilisation perspective. Tissue microarrays were constructed from 39 Merkel cell carcinomas, 24 small-cell lung carcinomas, and 18 extrapulmonary visceral small-cell carcinomas. SV40 large T antigen immunohistochemistry (clone PAb416) was performed; MCPyV large T antigen immunohistochemistry (clone CM2B4) had been previously performed. UniProt was used to compare the amino acid sequences of the SV40, BK, JC and MCPyV large T antigens, focusing on areas recognised by the PAb416 and CM2B4 clones. SV40 immunohistochemistry was negative in all tumours; MCPyV immunohistochemistry was positive in 38% of Merkel cell carcinomas and in 0% of non-cutaneous poorly differentiated neuroendocrine carcinomas. UniProt analysis revealed a high degree of similarity between SV40, BK, and JC viruses in the region recognised by PAb416. There was less homology between SV40 and MCPyV in this region, which was also interrupted by two long stretches of amino acids unique to MCPyV. The CM2B4 clone recognises a unique epitope in one of these stretches. The PAb416 antibody against the SV40 large T antigen does not cross-react with MCPyV large T antigen, and thus does not label Merkel cell carcinoma. © 2018 John Wiley & Sons Ltd.

The monetary value of the man-mSv for Korean NPP radiation workers assessed by the radiation aversion factor

International Nuclear Information System (INIS)

Lee, B. I.; Suh, D. H.; Kim, S. I.; Jeong, M. S.; Lim, Y. K.

2008-01-01

The monetary value of the man-mSv for operators of Korean nuclear power plants (NPPs) was calculated using a radiation aversion factor based on a survey of NPP workers. Initially, the life expectancy in the population is 79.4 y, the average age of cancer occurrence is 60 y, the average annual wage for an electric worker is 56 000 $ y -1 and the nominal risk coefficient induced by radiation is 4.2 E-5 mSv were used to evaluate the basic monetary value (α base) resulting in 45.6 $ mSv -1 . To investigate the degree of radiation aversion, the subject of the investigation was selected as the working radiation workers in 10 NPPs in Korea (Kori 1-2, Yeonggwang 1-3, Ulchin 1-3 and Wolseong 1-2). In August 2010, with the cooperation of KHNP and partner companies, a total of 2500 survey questionnaires to 10 NPPs (or 250 surveys to each NPP) were distributed to currently employed radiation workers. From these, 2157 responses were obtained between August and October 2010. The assessed radiation aversion factor and the monetary value of the man-mSv from the calculated radiation aversion factor were 1.26 and ∼50 $ in the 0-1 mSv range, 1.38 and ∼200 $ in the 1-5 mSv range, 1.52 and ∼1000 $ in the 5-10 mSv range, 1.65 and ∼4000 $ in the 10-20 mSv range and 1.74 and ∼8500 $ >20 mSv. (authors)

Influences of prolonged apnea and oxygen inhalation on pulmonary hemodynamics during breath holding: Quantitative assessment by velocity-encoded MR imaging with SENSE technique

International Nuclear Information System (INIS)

Nogami, Munenobu; Ohno, Yoshiharu; Higashino, Takanori; Takenaka, Daisuke; Yoshikawa, Takeshi; Koyama, Hisanobu; Kawamitsu, Hideaki; Fujii, Masahiko; Sugimura, Kazuro

2007-01-01

Purpose: The purpose of our study was to assess the influence of prolonged apnea and administration of oxygen on pulmonary hemodynamics during breath holding (BH) by using velocity-encoded MR imaging combined with the SENSE technique (velocity MRI). Materials and methods: Ten healthy male volunteers underwent velocity MRI during BH with and without O 2 inhalation. All velocity MRI data sets were obtained continuously with the 2D cine phase-contrast method during a single BH period. The data were then divided into three BH time phases as follows: first, second and third. To evaluate the influence of prolonged apnea on hemodynamics, stroke volume (SV) and maximal change in flow rate during ejection (MCFR) of second and third phases were statistically compared with those of first phase by using the ANOVA followed by Turkey's HSD multiple comparison test. To assess the influence of O 2 on hemodynamics, SV and MCFR with or without O 2 were compared by the paired t-test. To assess the measuring agreement of hemodynamic indices during prolonged breath holding, Bland-Altman's analysis was performed. Results: Prolonged apnea had no significant influence on SV and MCFR regardless of administration of O 2 (p > 0.05). Mean MCFR for all phases was significantly lower with administration of O 2 than without (p 2 were smaller than without. Conclusion: O 2 inhalation modulated maximal change in flow rate during ejection, and did not influence stroke volume during breath holding. Influence of O 2 inhalation should be considered for MR measurements of pulmonary hemodynamics during breath holding

A biochemical marker panel in MRI-proven hyperacute ischemic stroke-a prospective study

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Knauer Carolin

2012-03-01

Full Text Available Abstract Background Computer tomography (CT is still the fastest and most robust technique to rule out ICH in acute stroke. However CT-sensitivity for detection of ischemic stroke in the hyperacute phase is still relatively low. Moreover the validity of pure clinical judgment is diminished by several stroke imitating diseases (mimics. The "Triage® Stroke Panel", a biochemical multimarker assay, detects Brain Natriuretic Peptide (BNP, D-Dimers (DD, Matrix-Metalloproteinase-9 (MMP-9, and S100B protein and promptly generates a Multimarkerindex of these values (MMX. This index has been licensed for diagnostic purposes as it might increase the validity of the clinical diagnosis to differentiate between stroke imitating diseases and true ischemic strokes. Our aim was to prove whether the panel is a reliable indicating device for the diagnosis of ischemic stroke in a time window of 6 h to fasten the pre- and intrahospital pathway to fibrinolysis. Methods We investigated all consecutive patients admitted to our stroke unit during a time period of 5 months. Only patients with clinical investigation, blood sample collection and MRI within six hours from symptom onset were included. Values of biochemical markers were analyzed according to the results of diffusion weighted MR-imaging. In addition MMX-values in ischemic strokes were correlated with the TOAST-criteria. For statistical analysis the SAS Analyst software was used. Correlation coefficients were analyzed and comparison tests for two or more groups were performed. Statistical significance was assumed in case of p Results In total 174 patients were included into this study (n = 100 strokes, n = 49 mimics, n = 25 transitoric ischemic attacks. In patients with ischemic strokes the mean NIHSS was 7.6 ± 6.2, while the mean DWI-lesion volume was 20.6 ml (range 186.9 to 4.2 ml. According to the MMX or the individual markers there was no statistically significant difference between the group of ischemic

Measuring marine iron(III) complexes by CLE-AdSV

NARCIS (Netherlands)

Town, R.M.; Leeuwen, van H.P.

2005-01-01

Iron(iii) speciation data, as determined by competitive ligand exchange?adsorptive stripping voltammetry (CLE-AdSV), is reconsidered in the light of the kinetic features of the measurement. The very large stability constants reported for iron(iii) in marine ecosystems are shown to be possibly due to

Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated ras oncogene and SV40 T-antigen.

Science.gov (United States)

Su, L N; Little, J B

1992-08-01

Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. Cells transfected with EJ ras alone showed no morphological alterations nor significant changes in radiosensitivity. Cell clones expressing ras and/or SV40 T-antigen showed a reduced requirement for serum supplements, an increase in aneuploidy and chromosomal aberrations, and enhanced growth in soft agar as an early cellular response to SV40 T-antigen expression. The sequential order of transfection with SV40 T-antigen and ras influenced radio-sensitivity but not the induction of morphological changes. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself.

Determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke from baryonic Λ{sub b} decays

Energy Technology Data Exchange (ETDEWEB)

Hsiao, Y.K. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Geng, C.Q. [Shanxi Normal University, School of Physics and Information Engineering, Linfen (China); National Tsing Hua University, Department of Physics, Hsinchu (China); Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Applications (SICQEA), Changsha (China)

2017-10-15

We present the first attempt to extract vertical stroke V{sub cb} vertical stroke from the Λ{sub b} → Λ{sub c}{sup +}l anti ν{sub l} decay without relying on vertical stroke V{sub ub} vertical stroke inputs from the B meson decays. Meanwhile, the hadronic Λ{sub b} → Λ{sub c}M{sub (c)} decays with M = (π{sup -},K{sup -}) and M{sub c} =(D{sup -},D{sup -}{sub s}) measured with high precisions are involved in the extraction. Explicitly, we find that vertical stroke V{sub cb} vertical stroke =(44.6 ± 3.2) x 10{sup -3}, agreeing with the value of (42.11 ± 0.74) x 10{sup -3} from the inclusive B → X{sub c}l anti ν{sub l} decays. Furthermore, based on the most recent ratio of vertical stroke V{sub ub} vertical stroke / vertical stroke V{sub cb} vertical stroke from the exclusive modes, we obtain vertical stroke V{sub ub} vertical stroke = (4.3 ± 0.4) x 10{sup -3}, which is close to the value of (4.49 ± 0.24) x 10{sup -3} from the inclusive B → X{sub u}l anti ν{sub l} decays. We conclude that our determinations of vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke favor the corresponding inclusive extractions in the B decays. (orig.)

Continuum limit of gl(M vertical stroke N) spin chains

International Nuclear Information System (INIS)

Candu, Constantin

2011-03-01

We study the spectrum of an integrable antiferromagnetic Hamiltonian of the gl(M vertical stroke N) spin chain of alternating fundamental and dual representations. After extensive numerical analysis, we identify the vacuum and low lying excitations and with this knowledge perform the continuum limit, while keeping a finite gap. All antiferromagnetic gl(n+N vertical stroke N) spin chains with n>0 and N≠0 are shown to possess in the continuum limit 2n-2 multiplets of massive particles which scatter with gl(n) Gross-Neveu like S-matrices, namely their eigenvalues do not depend on N. We argue that the continuum theory is the gl(M vertical stroke N) Gross-Neveu model, that is the massive deformation of the gl(M vertical stroke N) 1 Wess-Zumino-Witten model. As we can see ion the example of gl(2m vertical stroke 1) spin chains, the full particle spectrum is much richer. Our analysis suggests that for a complete characterization of the latter it is not enough to restrict to large volume calculations, as we do in this work. (orig.)

Interleukin-6 is increased in plasma and cerebrospinal fluid of community-dwelling domestic dogs with acute ischaemic stroke

DEFF Research Database (Denmark)

Gredal, Hanne; Thomsen, Barbara B; Boza-Serrano, Antonio

2017-01-01

itself contributes towards the cytokine response. Community-dwelling domestic dogs suffer from spontaneous ischaemic stroke, and therefore, offer the opportunity to study the cytokine response in a noninvasive set-up. The aims of this study were to investigate cytokine concentrations in plasma...... and cerebrospinal fluid (CSF) in dogs with acute ischaemic stroke and to search for correlations between infarct volume and cytokine concentrations. Blood and CSF were collected from dogs less than 72 h after a spontaneous ischaemic stroke. Infarct volumes were estimated on MRIs. Interleukin (IL)-2, IL-6, IL-8, IL......-10 and tumour necrosis factor in the plasma, CSF and brain homogenates were measured using a canine-specific multiplex immunoassay. IL-6 was significantly increased in plasma (P = 0.04) and CSF (P = 0.04) in stroke dogs compared with healthy controls. The concentrations of other cytokines...

Cryptogenic Stroke

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Mohammad Saadatnia

2017-02-01

Full Text Available Cryptogenic stroke is defined as brain infarction that is not attributable to a source of definite embolism, large artery atherosclerosis, or small artery disease despite a thorough vascular, cardiac, and serologic evaluation. Despite many advances in our understanding of ischemic stroke, cryptogenic strokes remain a diagnostic and therapeutic challenge. The pathophysiology of cryptogenic stroke is likely various. Probable mechanisms include cardiac embolism secondary to occult paroxysmal atrial fibrillation, aortic atheromatous disease or other cardiac sources, paradoxical embolism from atrial septal abnormalities such as patent foramen ovale, hypercoagulable states, and preclinical or subclinical cerebrovascular disease.  Cryptogenic stroke is one-fourth among cerebral infarction, but most of them could be ascribed to embolic stroke. A significant proportion of cryptogenic strokes adhere to embolic infarct topography on brain imaging and improvement in our ability to detect paroxysmal atrial fibrillation in patients with cryptogenic stroke has strengthened the idea that these strokes are embolic in nature. a significant proportion of cryptogenic strokes adhere to embolic infarct topography on brain imaging.embolic stroke of undetermined sources(ESUS was planned for unifying embolic stroke of undetermined source.  The etiologies underlying ESUS included minor-risk potential cardioembolic sources, covert paroxysmal atrial fibrillation, cancer-associated coagulopathy and embolism, arteriogenic emboli, and paroxysmal embolism. Extensive evaluation including transesophageal echocardiography and cardiac monitoring for long time could identify the etiology of these patients. Therefore cryptogenic stroke is a diagnosis of exclusion. Compared with other stroke subtypes, cryptogenic stroke tends to have a better prognosis and lower long-term risk of recurrence.

Effect of head rotation on cerebral blood velocity in the prone position

DEFF Research Database (Denmark)

Højlund, Jakob; Sandmand, Marie; Sonne, Morten

2012-01-01

for cerebral blood flow. We tested in healthy subjects the hypothesis that rotating the head in the prone position reduces cerebral blood flow. Methods. Mean arterial blood pressure (MAP), stroke volume (SV), and CO were determined, together with the middle cerebral artery mean blood velocity (MCA V...... V(mean) ~10% in spite of an elevated MAP. Prone positioning with rotated head affects both CBF and cerebrovenous drainage indicating that optimal brain perfusion requires head centering....

Generation of a Vero-Based Packaging Cell Line to Produce SV40 Gene Delivery Vectors for Use in Clinical Gene Therapy Studies

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Miguel G. Toscano

2017-09-01

Full Text Available Replication-defective (RD recombinant simian virus 40 (SV40-based gene delivery vectors hold a great potential for clinical applications because of their presumed non-immunogenicity and capacity to induce immune tolerance to the transgene products in humans. However, the clinical use of SV40 vectors has been hampered by the lack of a packaging cell line that produces replication-competent (RC free SV40 particles in the vector production process. To solve this problem, we have adapted the current SV40 vector genome used for the production of vector particles and generated a novel Vero-based packaging cell line named SuperVero that exclusively expresses the SV40 large T antigen. SuperVero cells produce similar numbers of SV40 vector particles compared to the currently used packaging cell lines, albeit in the absence of contaminating RC SV40 particles. Our unique SV40 vector platform named SVac paves the way to clinically test a whole new generation of SV40-based therapeutics for a broad range of important diseases.

Objectively assessed physical activity and associated factors of sedentary behavior among survivors of stroke living in Cape Town, South Africa.

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Joseph, Conran; Conradsson, David; Hagströmer, Maria; Lawal, Isa; Rhoda, Anthea

2017-06-18

To investigate objectively measured physical activity in stroke survivors living in low-income areas of Cape Town, South Africa, specifically to: (a) describe the volume of daily physical activity and time spent in different intensity levels and (b) investigate the association of factors covering the International Classification of Functioning, Disability and Health with sedentary behavior. A cross-sectional design was used, where forty-five ambulatory community-dwelling stroke survivors participated. Volume and intensity of physical activity were assessed with accelerometers for three to five consecutive days. Personal and environmental factors, along with body function and activity, were captured. Multiple linear regression was used to investigate factors associated with the percentage of days spent sedentary. The median number of steps per day was 2393, and of the average 703 minutes of wear time, 80% were spent in sedentary, 15% in light, and 5% in moderate-to-vigorous intensity physical activity. Age, stroke severity, and failing to receive outpatient rehabilitation were independently associated with sedentary, which, taken together, explained 52% of the variance. Low volumes of physical activity and high amount of sedentary time emphasize the need to develop strategies that will increase physical activity. Providing outpatient rehabilitation in a systematic manner post-stroke is a potential target of health care programs in order to reduce sedentary behavior. Implications for rehabilitation Objectively measured physical activity among community-dwelling survivors of stroke in Cape Town, South Africa was low in volume, and the majority did not meet the recommendations of 150 minutes of at least moderate intensity physical activity. The majority of stroke survivors in South Africa spent most of their time sedentary, which could further increase the risk of cardiovascular impairments. Outpatient rehabilitation should be provided to all patients after stroke

The Combination of Micro Diaphragm Pumps and Flow Sensors for Single Stroke Based Liquid Flow Control.

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Jenke, Christoph; Pallejà Rubio, Jaume; Kibler, Sebastian; Häfner, Johannes; Richter, Martin; Kutter, Christoph

2017-04-03

With the combination of micropumps and flow sensors, highly accurate and secure closed-loop controlled micro dosing systems for liquids are possible. Implementing a single stroke based control mode with piezoelectrically driven micro diaphragm pumps can provide a solution for dosing of volumes down to nanoliters or variable average flow rates in the range of nL/min to μL/min. However, sensor technologies feature a yet undetermined accuracy for measuring highly pulsatile micropump flow. Two miniaturizable in-line sensor types providing electrical readout-differential pressure based flow sensors and thermal calorimetric flow sensors-are evaluated for their suitability of combining them with mircopumps. Single stroke based calibration of the sensors was carried out with a new method, comparing displacement volumes and sensor flow volumes. Limitations of accuracy and performance for single stroke based flow control are described. Results showed that besides particle robustness of sensors, controlling resistive and capacitive damping are key aspects for setting up reproducible and reliable liquid dosing systems. Depending on the required average flow or defined volume, dosing systems with an accuracy of better than 5% for the differential pressure based sensor and better than 6.5% for the thermal calorimeter were achieved.

Late night activity regarding stroke codes: LuNAR strokes.

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Tafreshi, Gilda; Raman, Rema; Ernstrom, Karin; Rapp, Karen; Meyer, Brett C

2012-08-01

There is diurnal variation for cardiac arrest and sudden cardiac death. Stroke may show a similar pattern. We assessed whether strokes presenting during a particular time of day or night are more likely of vascular etiology. To compare emergency department stroke codes arriving between 22:00 and 8:00 hours (LuNAR strokes) vs. others (n-LuNAR strokes). The purpose was to determine if late night strokes are more likely to be true strokes or warrant acute tissue plasminogen activator evaluations. We reviewed prospectively collected cases in the University of California, San Diego Stroke Team database gathered over a four-year period. Stroke codes at six emergency departments were classified based on arrival time. Those arriving between 22:00 and 8:00 hours were classified as LuNAR stroke codes, the remainder were classified as 'n-LuNAR'. Patients were further classified as intracerebral hemorrhage, acute ischemic stroke not receiving tissue plasminogen activator, acute ischemic stroke receiving tissue plasminogen activator, transient ischemic attack, and nonstroke. Categorical outcomes were compared using Fisher's Exact test. Continuous outcomes were compared using Wilcoxon's Rank-sum test. A total of 1607 patients were included in our study, of which, 299 (19%) were LuNAR code strokes. The overall median NIHSS was five, higher in the LuNAR group (n-LuNAR 5, LuNAR 7; P=0·022). There was no overall differences in patient diagnoses between LuNAR and n-LuNAR strokes (P=0·169) or diagnosis of acute ischemic stroke receiving tissue plasminogen activator (n-LuNAR 191 (14·6%), LuNAR 42 (14·0%); P=0·86). Mean arrival to computed tomography scan time was longer during LuNAR hours (n-LuNAR 54·9±76·3 min, LuNAR 62·5±87·7 min; P=0·027). There was no significant difference in 90-day mortality (n-LuNAR 15·0%, LuNAR 13·2%; P=0·45). Our stroke center experience showed no difference in diagnosis of acute ischemic stroke between day and night stroke codes. This

GABA(A)-benzodiazepine receptor complex sensitivity in 5-HT(1A) receptor knockout mice on a 129/Sv background.

NARCIS (Netherlands)

Pattij, T.; Groenink, L.; Oosting, R.S.; Gugten, J. van der; Maes, R.A.A.; Olivier, B.

2002-01-01

Previous studies in 5-HT(1A) receptor knockout (1AKO) mice on a mixed Swiss Websterx129/Sv (SWx129/Sv) and a pure 129/Sv genetic background suggest a differential gamma-aminobutyric acid (GABA(A))-benzodiazepine receptor complex sensitivity in both strains, independent from the anxious phenotype. To

Metabolic Syndrome Predicts Refractoriness to Intravenous Thrombolysis in Acute Ischemic Stroke.

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Dorado, Laura; Arenillas, Juan F; López-Cancio, Elena; Hernández-Pérez, María; Pérez de la Ossa, Natalia; Gomis, Meritxell; Millán, Mònica; Granada, María Luisa; Galán, Amparo; Palomeras, Ernest; Dávalos, Antoni

2015-11-01

Metabolic syndrome (MetS) has been associated with higher resistance to clot lysis at 24 hours after tissue plasminogen activator (tPA) administration in patients with acute ischemic stroke. We aimed to test this hypothesis at earlier time points, when neurointerventional rescue procedures may still be indicated to achieve arterial recanalization. This is a prospective and observational study in consecutive stroke patients with MCA occlusion treated with IV tPA. MetS was diagnosed following the unified criteria of the last Joint Interim Statement 2009 participating several major organizations. The primary outcome variable was resistance to thrombolysis, defined as the absence of complete middle cerebral artery recanalization 2 hours after tPA bolus assessed by transcranial color-coded duplex or when rescue mechanical thrombectomy after IV tPA was required. Secondary outcome variables were dramatic neurological improvement (decrease in ≥10 points, or a National Institutes of Health Stroke Scale [NIHSS] score of 0-1 at 24 hours), symptomatic intracerebral hemorrhage following European-Australasian Acute Stroke Study II criteria, infarct volume at 24 hours (calculated by using the formula for irregular volumes, ABC/2), and good outcome (modified Rankin Scale score < 3) at 3 months. A total of 234 patients (median baseline NIHSS score 16 [10-20]) were included and 146 (62.4%) fulfilled MetS criteria. After multivariate analysis, MetS emerged as an independent predictor of resistance to thrombolysis (odds ratio = 2.2 [1.3-4.2], P = .01) and absence of dramatic neurological improvement (odds ratio = .5 [.28-.97], P = .04). In addition, MetS conferred poorer functional outcome, higher symptomatic intracerebral hemorrhage rate, and increased infarct volume, although these associations disappeared after adjustment for covariates. MetS predicts patients with middle cerebral artery occlusion refractory to early clot dissolution after IV tPA. This

Child-Mediated Stroke Communication: findings from Hip Hop Stroke.

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Williams, Olajide; DeSorbo, Alexandra; Noble, James; Gerin, William

2012-01-01

Low thrombolysis rates for acute ischemic stroke are linked to delays in seeking immediate treatment due to low public stroke awareness. We aimed to assess whether "Child-Mediated Stroke Communication" could improve stroke literacy of parents of children enrolled in a school-based stroke literacy program called Hip Hop Stroke. Parents of children aged 9 to 12 years from 2 public schools in Harlem, New York City, were recruited to participate in stroke literacy questionnaires before and after their child's participation in Hip Hop Stroke, a novel Child-Mediated Stroke Communication intervention delivered in school auditoriums. Parental recall of stroke information communicated through their child was assessed 1-week after the intervention. Fifth and sixth grade students (n=182) were enrolled into Hip Hop Stroke. One hundred two parents were approached in person to participate; 75 opted to participate and 71 completed both the pretest and post-test (74% response rate and 95% retention rate). Parental stroke literacy improved after the program; before the program, 3 parents of 75 (3.9%) were able to identify the 5 cardinal stroke symptoms, distracting symptom (chest pains), and had an urgent action plan (calling 911) compared with 21 of 71 parents (29.6%) postintervention (P<0.001). The FAST mnemonic was known by 2 (2.7%) of participants before the program versus 29 (41%) after program completion (P<0.001). Knowledge of stroke signs and symptoms remains low among residents of this high-risk population. The use of Child-Mediated Stroke Communication suggests that school children aged 9 to 12 years may be effective conduits of critical stroke knowledge to their parents.

Host-cell reactivation of ultraviolet-irradiated SV 40 DNA in five complementation groups of xeroderma pigmentosum

International Nuclear Information System (INIS)

Abrahams, P.J.; Eb, A.J. van der

1976-01-01

Host-cell reactivation of UV-irradiated double-stranded SV40 DNA was studied in BSC-1 monkey cells, normal human cells, heterozygous Xeroderma pigmentosum xp cells, representative cell strains of the five complemention groups of XP and in XP 'variant' cells. The following percentages of survival of the plaque-forming ability of double-stranded SV40 DNA were found in XP cells compared with the value found in normal monkey and human cells: groupA, 13%; group B, 30%; group C, 18%; group D, 14%; group E, 59%; and in the heterozygous XP cells almost 100%. The survival in XP 'variant' cells was 66%. The survival of single-stranded SV40 DNA in BSC-1 cells was much lower than that of double-stranded SV40 DNA in XP cells of complementation group A, which possibly indicates that some repair of UV damage occurs even in XP cells of group A

Behavior outcome after ischemic and hemorrhagic stroke, with similar brain damage, in rats.

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Mestriner, Régis Gemerasca; Miguel, Patrícia Maidana; Bagatini, Pamela Brambilla; Saur, Lisiani; Boisserand, Lígia Simões Braga; Baptista, Pedro Porto Alegre; Xavier, Léder Leal; Netto, Carlos Alexandre

2013-05-01

Stroke causes disability and mortality worldwide and is divided into ischemic and hemorrhagic subtypes. Although clinical trials suggest distinct recovery profiles for ischemic and hemorrhagic events, this is not conclusive due to stroke heterogeneity. The aim of this study was to produce similar brain damage, using experimental models of ischemic (IS) and hemorrhagic (HS) stroke and evaluate the motor spontaneous recovery profile. We used 31 Wistar rats divided into the following groups: Sham (n=7), ischemic (IS) (n=12) or hemorrhagic (HS) (n=12). Brain ischemia or hemorrhage was induced by endotelin-1 (ET-1) and collagenase type IV-S (collagenase) microinjections, respectively. All groups were evaluated in the open field, cylinder and ladder walk behavioral tests at distinct time points as from baseline to 30 days post-surgery (30 PS). Histological and morphometric analyses were used to assess the volume of lost tissue and lesion length. Present results reveal that both forms of experimental stroke had a comparable long-term pattern of damage, since no differences were found in volume of tissue lost or lesion size 30 days after surgery. However, behavioral data showed that hemorrhagic rats were less impaired at skilled walking than ischemic ones at 15 and 30 days post-surgery. We suggest that experimentally comparable stroke design is useful because it reduces heterogeneity and facilitates the assessment of neurobiological differences related to stroke subtypes; and that spontaneous skilled walking recovery differs between experimental ischemic and hemorrhagic insults. Copyright © 2013 Elsevier B.V. All rights reserved.

Risk adjustment for case mix and the effect of surgeon volume on morbidity.

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Maas, Matthew B; Jaff, Michael R; Rordorf, Guy A

2013-06-01

Retrospective studies of large administrative databases have shown higher mortality for procedures performed by low-volume surgeons, but the adequacy of risk adjustment in those studies is in doubt. To determine whether the relationship between surgeon volume and outcomes is an artifact of case mix using a prospective sample of carotid endarterectomy cases. Observational cohort study from January 1, 2008, through December 31, 2010, with preoperative, immediate postoperative, and 30-day postoperative assessments acquired by independent monitors. Urban, tertiary academic medical center. All 841 patients who underwent carotid endarterectomy performed by a vascular surgeon or cerebrovascular neurosurgeon at the institution. Carotid endarterectomy without another concurrent surgery. Stroke, death, and other surgical complications occurring within 30 days of surgery along with other case data. A low-volume surgeon performed 40 or fewer cases per year. Variables used in a comparison administrative database study, as well as variables identified by our univariate analysis, were used for adjusted analyses to assess for an association between low-volume surgeons and the rate of stroke and death as well as other complications. RESULTS The rate of stroke and death was 6.9% for low-volume surgeons and 2.0% for high-volume surgeons (P = .001). Complications were similarly higher (13.4% vs 7.2%, P = .008). Low-volume surgeons performed more nonelective cases. Low-volume surgeons were significantly associated with stroke and death in the unadjusted analysis as well as after adjustment with variables used in the administrative database study (odds ratio, 3.61; 95% CI, 1.70-7.67, and odds ratio, 3.68; 95% CI, 1.72-7.89, respectively). However, adjusting for the significant disparity of American Society of Anesthesiologists Physical Status classification in case mix eliminated the effect of surgeon volume on the rate of stroke and death (odds ratio, 1.65; 95% CI, 0.59-4.64) and other

SV40 host-substituted variants: a new look at the monkey DNA inserts and recombinant junctions.

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Singer, Maxine; Winocour, Ernest

2011-04-10

The available monkey genomic data banks were examined in order to determine the chromosomal locations of the host DNA inserts in 8 host-substituted SV40 variant DNAs. Five of the 8 variants contained more than one linked monkey DNA insert per tandem repeat unit and in all cases but one, the 19 monkey DNA inserts in the 8 variants mapped to different locations in the monkey genome. The 50 parental DNAs (32 monkey and 18 SV40 DNA segments) which spanned the crossover and flanking regions that participated in monkey/monkey and monkey/SV40 recombinations were characterized by substantial levels of microhomology of up to 8 nucleotides in length; the parental DNAs also exhibited direct and inverted repeats at or adjacent to the crossover sequences. We discuss how the host-substituted SV40 variants arose and the nature of the recombination mechanisms involved. Copyright © 2011 Elsevier Inc. All rights reserved.

Stroke Treatments

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... Stroke Association.org Professionals for Stroke Association.org Shop for Stroke Association.org Support for Stroke Association. ... works by dissolving the clot and improving blood flow to the part of the brain being deprived ...

Post-stroke depression among stroke survivors attending two ...

African Journals Online (AJOL)

Background: The burden of stroke worldwide is increasing rapidly. There is paucity of data on post-stroke depression (PSD) among stroke survivors in Uganda, despite the high prevalence of PSD reported elsewhere. Methods: In a cross-sectional study, we assessed adult participants with confirmed first stroke with a ...

Assessment of left ventricular myocardial function using 16-slice multidetector-row computed tomography: comparison with magnetic resonance imaging and echocardiography

International Nuclear Information System (INIS)

Heuschmid, Martin; Rothfuss, Julia K.; Fenchel, Michael; Stauder, Norbert; Kuettner, Axel; Miller, Stephan; Claussen, Claus D.; Kopp, Andreas F.; Schroeder, Stephen; Burgstahler, Christof; Franow, Andreas; Kuzo, Ronald S.

2006-01-01

To assess functional parameters using multidetector-row computed tomography (MDCT) and echocardiography and to compare the results with magnetic resonance imaging (MRI). End-diastolic-volume (EDV), end-systolic-volume (ESV), stroke-volume (SV), ejection-fraction (EF), and myocardial mass (MM) were calculated based on CT data sets from 52 patients. Echocardiography was performed in 24 of the 52 patients. The results from MDCT and echocardiography were compared with MRI. A strong correlation between MDCT and MRI (r=0.66-0.90) was found for all parameters. Echocardiography revealed a low or moderate correlation (0.05-0.59). Compared to MRI the average differences with MDCT were for EDV 15.1 ml, ESV 10.6 ml, SV 4.5 ml, EF 1.8%, and MM 8.2 g, for EDV determined by echocardiography 36.2 ml, ESV 6.8 ml, and EF 13.9%. Bland-Altman analysis revealed acceptable limits of agreement between MRI and MDCT. MDCT enables reliable quantification of left ventricular function. Echocardiography was found to have only a moderate agreement of functional parameters with MRI. (orig.)

Comparison of compensatory reserve during lower-body negative pressure and hemorrhage in nonhuman primates.

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Hinojosa-Laborde, Carmen; Howard, Jeffrey T; Mulligan, Jane; Grudic, Greg Z; Convertino, Victor A

2016-06-01

Compensatory reserve was measured in baboons (n = 13) during hemorrhage (Hem) and lower-body negative pressure (LBNP) using a machine-learning algorithm developed to estimate compensatory reserve by detecting reductions in central blood volume during LBNP. The algorithm calculates compensatory reserve index (CRI) from normovolemia (CRI = 1) to cardiovascular decompensation (CRI = 0). The hypothesis was that Hem and LBNP will elicit similar CRI values and that CRI would have higher specificity than stroke volume (SV) in predicting decompensation. Blood was removed in four steps: 6.25%, 12.5%, 18.75%, and 25% of total blood volume. Four weeks after Hem, the same animals were subjected to four levels of LBNP that was matched on the basis of their central venous pressure. Data (mean ± 95% confidence interval) indicate that CRI decreased (P AUC in Hem (0.94 vs. 0.84) and LBNP (0.94 vs. 0.92). These data support the hypothesis that Hem and LBNP elicited the same CRI response, suggesting that measurement of compensatory reserve is superior to SV as a predictor of cardiovascular decompensation.

[Neuroimaging and Blood Biomarkers in Functional Prognosis after Stroke].

Science.gov (United States)

Branco, João Paulo; Costa, Joana Santos; Sargento-Freitas, João; Oliveira, Sandra; Mendes, Bruno; Laíns, Jorge; Pinheiro, João

2016-11-01

Stroke remains one of the leading causes of morbidity and mortality around the world and it is associated with an important long-term functional disability. Some neuroimaging resources and certain peripheral blood or cerebrospinal fluid proteins can give important information about etiology, therapeutic approach, follow-up and functional prognosis in acute ischemic stroke patients. However, among the scientific community, there is currently more interest in the stroke vital prognosis over the functional prognosis. Predicting the functional prognosis during acute phase would allow more objective rehabilitation programs and better management of the available resources. The aim of this work is to review the potential role of acute phase neuroimaging and blood biomarkers as functional recovery predictors after ischemic stroke. Review of the literature published between 2005 and 2015, in English, using the terms "ischemic stroke", "neuroimaging" e "blood biomarkers". We included nine studies, based on abstract reading. Computerized tomography, transcranial doppler ultrasound and diffuse magnetic resonance imaging show potential predictive value, based on the blood flow study and the evaluation of stroke's volume and localization, especially when combined with the National Institutes of Health Stroke Scale. Several biomarkers have been studied as diagnostic, risk stratification and prognostic tools, namely the S100 calcium binding protein B, C-reactive protein, matrix metalloproteinases and cerebral natriuretic peptide. Although some biomarkers and neuroimaging techniques have potential predictive value, none of the studies were able to support its use, alone or in association, as a clinically useful functionality predictor model. All the evaluated markers were considered insufficient to predict functional prognosis at three months, when applied in the first hours after stroke. Additional studies are necessary to identify reliable predictive markers for functional

Predicting Hemorrhagic Transformation of Acute Ischemic Stroke: Prospective Validation of the HeRS Score.

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Marsh, Elisabeth B; Llinas, Rafael H; Schneider, Andrea L C; Hillis, Argye E; Lawrence, Erin; Dziedzic, Peter; Gottesman, Rebecca F

2016-01-01

Hemorrhagic transformation (HT) increases the morbidity and mortality of ischemic stroke. Anticoagulation is often indicated in patients with atrial fibrillation, low ejection fraction, or mechanical valves who are hospitalized with acute stroke, but increases the risk of HT. Risk quantification would be useful. Prior studies have investigated risk of systemic hemorrhage in anticoagulated patients, but none looked specifically at HT. In our previously published work, age, infarct volume, and estimated glomerular filtration rate (eGFR) significantly predicted HT. We created the hemorrhage risk stratification (HeRS) score based on regression coefficients in multivariable modeling and now determine its validity in a prospectively followed inpatient cohort.A total of 241 consecutive patients presenting to 2 academic stroke centers with acute ischemic stroke and an indication for anticoagulation over a 2.75-year period were included. Neuroimaging was evaluated for infarct volume and HT. Hemorrhages were classified as symptomatic versus asymptomatic, and by severity. HeRS scores were calculated for each patient and compared to actual hemorrhage status using receiver operating curve analysis.Area under the curve (AUC) comparing predicted odds of hemorrhage (HeRS score) to actual hemorrhage status was 0.701. Serum glucose (P hemorrhages were more likely to be symptomatic and more severe.The HeRS score is a valid predictor of HT in patients with ischemic stroke and indication for anticoagulation.

Risk Factors and Stroke Characteristic in Patients with Postoperative Strokes.

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Dong, Yi; Cao, Wenjie; Cheng, Xin; Fang, Kun; Zhang, Xiaolong; Gu, Yuxiang; Leng, Bing; Dong, Qiang

2017-07-01

Intravenous thrombolysis and intra-arterial thrombectomy are now the standard therapies for patients with acute ischemic stroke. In-house strokes have often been overlooked even at stroke centers and there is no consensus on how they should be managed. Perioperative stroke happens rather frequently but treatment protocol is lacking, In China, the issue of in-house strokes has not been explored. The aim of this study is to explore the current management of in-house stroke and identify the common risk factors associated with perioperative strokes. Altogether, 51,841 patients were admitted to a tertiary hospital in Shanghai and the records of those who had a neurological consult for stroke were reviewed. Their demographics, clinical characteristics, in-hospital complications and operations, and management plans were prospectively studied. Routine laboratory test results and risk factors of these patients were analyzed by multiple logistic regression model. From January 1, 2015, to December 31, 2015, over 1800 patients had neurological consultations. Among these patients, 37 had an in-house stroke and 20 had more severe stroke during the postoperative period. Compared to in-house stroke patients without a procedure or operation, leukocytosis and elevated fasting glucose levels were more common in perioperative strokes. In multiple logistic regression model, perioperative strokes were more likely related to large vessel occlusion. Patients with perioperative strokes had different risk factors and severity from other in-house strokes. For these patients, obtaining a neurological consultation prior to surgery may be appropriate in order to evaluate the risk of perioperative stroke. Copyright © 2017. Published by Elsevier Inc.

A high-quality narrow passband filter for elastic SV waves via aligned parallel separated thin polymethylmethacrylate plates

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Jun Zhang

2017-08-01

Full Text Available We designed a high-quality filter that consists of aligned parallel polymethylmethacrylate (PMMA thin plates with small gaps for elastic SV waves propagate in metals. Both the theoretical model and the full numerical simulation show the transmission spectrum of the elastic SV waves through such a filter has several sharp peaks with flawless transmission within the investigated frequencies. These peaks can be readily tuned by manipulating the geometry parameters of the PMMA plates. Our investigation finds that the same filter performs well for different metals where the elastic SV waves propagated.

Chimeric SV40 virus-like particles induce specific cytotoxicity and protective immunity against influenza A virus without the need of adjuvants.

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Kawano, Masaaki; Morikawa, Katsuma; Suda, Tatsuya; Ohno, Naohito; Matsushita, Sho; Akatsuka, Toshitaka; Handa, Hiroshi; Matsui, Masanori

2014-01-05

Virus-like particles (VLPs) are a promising vaccine platform due to the safety and efficiency. However, it is still unclear whether polyomavirus-based VLPs are useful for this purpose. Here, we attempted to evaluate the potential of polyomavirus VLPs for the antiviral vaccine using simian virus 40 (SV40). We constructed chimeric SV40-VLPs carrying an HLA-A*02:01-restricted, cytotoxic T lymphocyte (CTL) epitope derived from influenza A virus. HLA-A*02:01-transgenic mice were then immunized with the chimeric SV40-VLPs. The chimeric SV40-VLPs effectively induced influenza-specific CTLs and heterosubtypic protection against influenza A viruses without the need of adjuvants. Because DNase I treatment of the chimeric SV40-VLPs did not disrupt CTL induction, the intrinsic adjuvant property may not result from DNA contaminants in the VLP preparation. In addition, immunization with the chimeric SV40-VLPs generated long-lasting memory CTLs. We here propose that the chimeric SV40-VLPs harboring an epitope may be a promising CTL-based vaccine platform with self-adjuvant properties. © 2013 Elsevier Inc. All rights reserved.

Heart Performance Determination by Visualization in Larval Fishes: Influence of Alternative Models for Heart Shape and Volume

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Prescilla Perrichon

2017-07-01

Full Text Available Understanding cardiac function in developing larval fishes is crucial for assessing their physiological condition and overall health. Cardiac output measurements in transparent fish larvae and other vertebrates have long been made by analyzing videos of the beating heart, and modeling this structure using a conventional simple prolate spheroid shape model. However, the larval fish heart changes shape during early development and subsequent maturation, but no consideration has been made of the effect of different heart geometries on cardiac output estimation. The present study assessed the validity of three different heart models (the “standard” prolate spheroid model as well as a cylinder and cone tip + cylinder model applied to digital images of complete cardiac cycles in larval mahi-mahi and red drum. The inherent error of each model was determined to allow for more precise calculation of stroke volume and cardiac output. The conventional prolate spheroid and cone tip + cylinder models yielded significantly different stroke volume values at 56 hpf in red drum and from 56 to 104 hpf in mahi. End-diastolic and stroke volumes modeled by just a simple cylinder shape were 30–50% higher compared to the conventional prolate spheroid. However, when these values of stroke volume multiplied by heart rate to calculate cardiac output, no significant differences between models emerged because of considerable variability in heart rate. Essentially, the conventional prolate spheroid shape model provides the simplest measurement with lowest variability of stroke volume and cardiac output. However, assessment of heart function—especially if stroke volume is the focus of the study—should consider larval heart shape, with different models being applied on a species-by-species and developmental stage-by-stage basis for best estimation of cardiac output.

Impaired CK1 delta activity attenuates SV40-induced cellular transformation in vitro and mouse mammary carcinogenesis in vivo.

Directory of Open Access Journals (Sweden)

Heidrun Hirner

Full Text Available Simian virus 40 (SV40 is a powerful tool to study cellular transformation in vitro, as well as tumor development and progression in vivo. Various cellular kinases, among them members of the CK1 family, play an important role in modulating the transforming activity of SV40, including the transforming activity of T-Ag, the major transforming protein of SV40, itself. Here we characterized the effects of mutant CK1δ variants with impaired kinase activity on SV40-induced cell transformation in vitro, and on SV40-induced mammary carcinogenesis in vivo in a transgenic/bi-transgenic mouse model. CK1δ mutants exhibited a reduced kinase activity compared to wtCK1δ in in vitro kinase assays. Molecular modeling studies suggested that mutation N172D, located within the substrate binding region, is mainly responsible for impaired mutCK1δ activity. When stably over-expressed in maximal transformed SV-52 cells, CK1δ mutants induced reversion to a minimal transformed phenotype by dominant-negative interference with endogenous wtCK1δ. To characterize the effects of CK1δ on SV40-induced mammary carcinogenesis, we generated transgenic mice expressing mutant CK1δ under the control of the whey acidic protein (WAP gene promoter, and crossed them with SV40 transgenic WAP-T-antigen (WAP-T mice. Both WAP-T mice as well as WAP-mutCK1δ/WAP-T bi-transgenic mice developed breast cancer. However, tumor incidence was lower and life span was significantly longer in WAP-mutCK1δ/WAP-T bi-transgenic animals. The reduced CK1δ activity did not affect early lesion formation during tumorigenesis, suggesting that impaired CK1δ activity reduces the probability for outgrowth of in situ carcinomas to invasive carcinomas. The different tumorigenic potential of SV40 in WAP-T and WAP-mutCK1δ/WAP-T tumors was also reflected by a significantly different expression of various genes known to be involved in tumor progression, specifically of those involved in wnt-signaling and DNA

Intracranial Pressure Elevation 24 Hours after Ischemic Stroke in Aged Rats is Prevented by Early, Short Hypothermia Treatment

Directory of Open Access Journals (Sweden)

Lucy Anne Murtha

2016-05-01

Full Text Available Stroke is predominantly a senescent disease, yet most preclinical studies investigate treatment in young animals. We recently demonstrated that short-duration hypothermia-treatment completely prevented the dramatic intracranial pressure (ICP rise seen post-stroke in young rats. Here, our aim was to investigate whether a similar ICP rise occurs in aged rats and to determine whether short-duration hypothermia is an effective treatment in aged animals. Experimental Middle Cerebral Artery occlusion (MCAo - 3 hour occlusion was performed on male Wistar rats aged 19-20 months. At one hour after stroke-onset, rats were randomized to 2.5 hours hypothermia-treatment (32.5 °C or normothermia (37 °C. ICP was monitored at baseline, for 3.5 hours post-occlusion, and at 24 hours post-stroke. Infarct and edema volumes were calculated from histology. Baseline pre-stroke ICP was 11.2 ± 3.3 mmHg across all animals. Twenty-four hours post-stroke, ICP was significantly higher in normothermic animals compared to hypothermia-treated animals (27.4 ± 18.2 mmHg vs. 8.0 ± 5.0 mmHg, p = 0.03. Infarct and edema volumes were not significantly different between groups. These data demonstrate ICP may also increase 24 hours post-stroke in aged rats, and that short-duration hypothermia treatment has a profound and sustained preventative effect. These findings may have important implications for the use of hypothermia in clinical trials of aged stroke patients.

An anatomical and psychophysical comparison of subjective verticals in patients with right brain damage.

Science.gov (United States)

Rousseaux, Marc; Braem, Bérenger; Honoré, Jacques; Saj, Arnaud

2015-08-01

Brain hemisphere lesions often cause a contralesional tilt of the subjective vertical (SV) a phenomenon related to spatial neglect and postural disorders. Depending on the method employed, different perceptual systems come into play when this gravitational vertical is assessed. Here, we compared the anatomical and psychophysical characteristics of modality-dependent SV biases in patients with right hemisphere stroke. The SV was measured with visual, haptic and visual-haptic modalities (SV, SVV, SVHV) in 46 patients with a relatively recent stroke. Voxel-based lesion-symptom mapping (performed with NPM(®)) was used to highlight brain areas in which lesions best explained the severity of task biases (p rights reserved.

Continuum limit of gl(M vertical stroke N) spin chains

Energy Technology Data Exchange (ETDEWEB)

Candu, Constantin [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Gruppe Theorie

2011-03-15

We study the spectrum of an integrable antiferromagnetic Hamiltonian of the gl(M vertical stroke N) spin chain of alternating fundamental and dual representations. After extensive numerical analysis, we identify the vacuum and low lying excitations and with this knowledge perform the continuum limit, while keeping a finite gap. All antiferromagnetic gl(n+N vertical stroke N) spin chains with n>0 and N{ne}0 are shown to possess in the continuum limit 2n-2 multiplets of massive particles which scatter with gl(n) Gross-Neveu like S-matrices, namely their eigenvalues do not depend on N. We argue that the continuum theory is the gl(M vertical stroke N) Gross-Neveu model, that is the massive deformation of the gl(M vertical stroke N){sub 1} Wess-Zumino-Witten model. As we can see ion the example of gl(2m vertical stroke 1) spin chains, the full particle spectrum is much richer. Our analysis suggests that for a complete characterization of the latter it is not enough to restrict to large volume calculations, as we do in this work. (orig.)

Hospital acquired pneumonia is linked to right hemispheric peri-insular stroke.

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André Kemmling

Full Text Available Hospital acquired pneumonia (HAP is a major complication of stroke. We sought to determine associations between infarction of specific brain regions and HAP.215 consecutive acute stroke patients with HAP (2003-2009 were carefully matched with 215 non-pneumonia controls by gender, then NIHSS, then age. Admission imaging and binary masks of infarction were registered to MNI-152 space. Regional atlas and voxel-based log-odds were calculated to assess the relationship between infarct location and the likelihood of HAP. An independently validated penalized conditional logistic regression model was used to identify HAP associated imaging regions.The HAP and control patients were well matched by gender (100%, age (95% within 5-years, NIHSS (98% within 1-point, infarct size, dysphagia, and six other clinical variables. Right hemispheric infarcts were more frequent in patients with HAP versus controls (43.3% vs. 34.0%, p = 0.054, whereas left hemispheric infarcts were more frequent in controls (56.7% vs. 44.7%, p = 0.012; there was no significant difference between groups in the rate of brainstem strokes (p = 1.0. Of the 10 most infarcted regions, only right insular cortex volume was different in HAP versus controls (20 vs. 12 ml, p = 0.02. In univariate analyses, the highest log-odds regions for pneumonia were right hemisphere, cerebellum, and brainstem. The best performing multivariate model selected 7 brain regions of infarction and 2 infarct volume-based variables independently associated with HAP.HAP is associated with right hemispheric peri-insular stroke. These associations may be related to autonomic modulation of immune mechanisms, supporting recent hypotheses of stroke mediated immune suppression.

A numerical study on bow shocks around the lightning return stroke channel

International Nuclear Information System (INIS)

Chen, Qiang; Chen, Bin; Yi, Yun; Chen, P. F.; Mao, Yunfei; Xiong, Run

2015-01-01

Bow shock structures are important to various hydrodynamics and magnetohydrodynamics (MHD) phenomena in geophysics and astrophysics. The formation and propagation of bow shocks around the lightning return stroke channel are investigated based on the self-similar motion theory and simulated with a two-dimensional Eulerian finite volume resistive radiation MHD code. In this framework, as verification of theoretical models, the evolving structures of many quantities, such as the plasma density, temperature, pressure, shock velocity, and magnetic field, can be obtained, which present all the characteristics of bow shocks in the lightning return stroke processes. The evolution characteristics and the configuration of the curved return stroke channels, e.g., the non-ideal effects and the scaling laws, are discussed in detail. The results may have applications for some observed features of the return stroke channels and other phenomena in the lightning discharge plasmas

Periodic Limb Movements and White Matter Hyperintensities in First-Ever Minor Stroke or High-Risk Transient Ischemic Attack.

Science.gov (United States)

Boulos, Mark I; Murray, Brian J; Muir, Ryan T; Gao, Fuqiang; Szilagyi, Gregory M; Huroy, Menal; Kiss, Alexander; Walters, Arthur S; Black, Sandra E; Lim, Andrew S; Swartz, Richard H

2017-03-01

Emerging evidence suggests that periodic limb movements (PLMs) may contribute to the development of cerebrovascular disease. White matter hyperintensities (WMHs), a widely accepted biomarker for cerebral small vessel disease, are associated with incident stroke and death. We evaluated the association between increased PLM indices and WMH burden in patients presenting with stroke or transient ischemic attack (TIA), while controlling for vascular risk factors and stroke severity. Thirty patients presenting within 2 weeks of a first-ever minor stroke or high-risk TIA were prospectively recruited. PLM severity was measured with polysomnography. WMH burden was quantified using the Age Related White Matter Changes (ARWMC) scale based on neuroimaging. Partial Spearman's rank-order correlations and multiple linear regression models tested the association between WMH burden and PLM severity. Greater WMH burden was correlated with elevated PLM index and stroke volume. Partial Spearman's rank-order correlations demonstrated that the relationship between WMH burden and PLM index persisted despite controlling for vascular risk factors. Multivariate linear regression models revealed that PLM index was a significant predictor of an elevated ARWMC score while controlling for age, stroke volume, stroke severity, hypertension, and apnea-hypopnea index. The quantity of PLMs was associated with WMH burden in patients with first-ever minor stroke or TIA. PLMs may be a risk factor for or marker of WMH burden, even after considering vascular risk factors and stroke severity. These results invite further investigation of PLMs as a potentially useful target to reduce WMH and stroke burden. © Sleep Research Society (SRS) 2016. All rights reserved. For permissions, please email: journals.permissions@oup.com

SV40 Assembly In Vivo and In Vitro

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Ariella Oppenheim

2008-01-01

Full Text Available The Simian virus 40 (SV40 capsid is a T = 7d icosahedral lattice ∼45 nm in diameter surrounding the ∼5 kb circular minichromosome. The outer shell is composed of 360 monomers of the major capsid protein VP1, tightly bound in 72 pentamers. VP1 is a jellyroll β-barrel, with extending N- and C-terminal arms. The N-terminal arms bind DNA and face the interior of the capsid. The flexible C-arms tie together the 72 pentamers in three distinct kinds of interactions, thus facilitating the formation of a T = 7 icosahedron from identical pentameric building blocks. Assembly in vivo was shown to occur by addition of capsomers around the DNA. We apply a combination of biochemical and genetic approaches to study SV40 assembly. Our in vivo and in vitro studies suggest the following model: one or two capsomers bind at a high affinity to ses, the viral DNA encapsidation signal, forming the nucleation centre for assembly. Next, multiple capsomers attach concomitantly, at lower affinity, around the minichromosome. This increases their local concentration facilitating rapid, cooperative assembly reaction. Formation of the icosahedron proceeds either by gradual addition of single pentamers to the growing shell or by concerted assembly of pentamer clusters.

The Combination of Micro Diaphragm Pumps and Flow Sensors for Single Stroke Based Liquid Flow Control

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Christoph Jenke

2017-04-01

Full Text Available With the combination of micropumps and flow sensors, highly accurate and secure closed-loop controlled micro dosing systems for liquids are possible. Implementing a single stroke based control mode with piezoelectrically driven micro diaphragm pumps can provide a solution for dosing of volumes down to nanoliters or variable average flow rates in the range of nL/min to μL/min. However, sensor technologies feature a yet undetermined accuracy for measuring highly pulsatile micropump flow. Two miniaturizable in-line sensor types providing electrical readout—differential pressure based flow sensors and thermal calorimetric flow sensors—are evaluated for their suitability of combining them with mircopumps. Single stroke based calibration of the sensors was carried out with a new method, comparing displacement volumes and sensor flow volumes. Limitations of accuracy and performance for single stroke based flow control are described. Results showed that besides particle robustness of sensors, controlling resistive and capacitive damping are key aspects for setting up reproducible and reliable liquid dosing systems. Depending on the required average flow or defined volume, dosing systems with an accuracy of better than 5% for the differential pressure based sensor and better than 6.5% for the thermal calorimeter were achieved.

Transformation of SV40-immortalized human uroepithelial cells by 3-methylcholanthrene increases IFN- and Large T Antigen-induced transcripts

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Easton Marilyn J

2010-02-01

Full Text Available Abstract Background Simian Virus 40 (SV40 immortalization followed by treatment of cells with 3-methylcholanthrene (3-MC has been used to elicit tumors in athymic mice. 3-MC carcinogenesis has been thoroughly studied, however gene-level interactions between 3-MC and SV40 that could have produced the observed tumors have not been explored. The commercially-available human uroepithelial cell lines were either SV40-immortalized (HUC or SV40-immortalized and then 3-MC-transformed (HUC-TC. Results To characterize the SV40 - 3MC interaction, we compared human gene expression in these cell lines using a human cancer array and confirmed selected changes by RT-PCR. Many viral Large T Antigen (Tag expression-related changes occurred in HUC-TC, and it is concluded that SV40 and 3-MC may act synergistically to transform cells. Changes noted in IFP 9-27, 2'-5' OAS, IF 56, MxA and MxAB were typical of those that occur in response to viral exposure and are part of the innate immune response. Because interferon is crucial to innate immune host defenses and many gene changes were interferon-related, we explored cellular growth responses to exogenous IFN-γ and found that treatment impeded growth in tumor, but not immortalized HUC on days 4 - 7. Cellular metabolism however, was inhibited in both cell types. We conclude that IFN-γ metabolic responses were functional in both cell lines, but IFN-γ anti-proliferative responses functioned only in tumor cells. Conclusions Synergism of SV40 with 3-MC or other environmental carcinogens may be of concern as SV40 is now endemic in 2-5.9% of the U.S. population. In addition, SV40-immortalization is a generally-accepted method used in many research materials, but the possibility of off-target effects in studies carried out using these cells has not been considered. We hope that our work will stimulate further study of this important phenomenon.

Clinical feasibility of a myocardial signal intensity threshold-based semi-automated cardiac magnetic resonance segmentation method

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Varga-Szemes, Akos; Schoepf, U.J.; Suranyi, Pal; De Cecco, Carlo N.; Fox, Mary A. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Muscogiuri, Giuseppe [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Rome ' ' Sapienza' ' , Department of Medical-Surgical Sciences and Translational Medicine, Rome (Italy); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Cannao, Paola M. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Milan, Scuola di Specializzazione in Radiodiagnostica, Milan (Italy); Renker, Matthias [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Kerckhoff Heart and Thorax Center, Bad Nauheim (Germany); Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Ruzsics, Balazs [Royal Liverpool and Broadgreen University Hospitals, Department of Cardiology, Liverpool (United Kingdom)

2016-05-15

To assess the accuracy and efficiency of a threshold-based, semi-automated cardiac MRI segmentation algorithm in comparison with conventional contour-based segmentation and aortic flow measurements. Short-axis cine images of 148 patients (55 ± 18 years, 81 men) were used to evaluate left ventricular (LV) volumes and mass (LVM) using conventional and threshold-based segmentations. Phase-contrast images were used to independently measure stroke volume (SV). LV parameters were evaluated by two independent readers. Evaluation times using the conventional and threshold-based methods were 8.4 ± 1.9 and 4.2 ± 1.3 min, respectively (P < 0.0001). LV parameters measured by the conventional and threshold-based methods, respectively, were end-diastolic volume (EDV) 146 ± 59 and 134 ± 53 ml; end-systolic volume (ESV) 64 ± 47 and 59 ± 46 ml; SV 82 ± 29 and 74 ± 28 ml (flow-based 74 ± 30 ml); ejection fraction (EF) 59 ± 16 and 58 ± 17 %; and LVM 141 ± 55 and 159 ± 58 g. Significant differences between the conventional and threshold-based methods were observed in EDV, ESV, and LVM measurements; SV from threshold-based and flow-based measurements were in agreement (P > 0.05) but were significantly different from conventional analysis (P < 0.05). Excellent inter-observer agreement was observed. Threshold-based LV segmentation provides improved accuracy and faster assessment compared to conventional contour-based methods. (orig.)

The Cardiovascular Effects of Obesity on Ventricular Function and Mass in Patients after Tetralogy of Fallot Repair.

Science.gov (United States)

Fogel, Mark A; Pawlowski, Thomas; Keller, Marc S; Cohen, Meryl S; Goldmuntz, Elizabeth; Diaz, Laura; Li, Christine; Whitehead, Kevin K; Harris, Matthew A

2015-08-01

To determine the cardiovascular effects of obesity on patients with tetralogy of Fallot (TOF) repair. Ventricular performance measures were compared between obese (body mass index [BMI] ≥95%), overweight (85% ≤BMI <95%), and normal weight subjects (BMI <85%) in a retrospective review of patients with TOF who underwent cardiac magnetic resonance from 2005-2010. Significance was P < .05. Of 260 consecutive patients with TOF, 32 were obese (12.3%), 48 were overweight (18.5%), and 180 were normal weight (69.2%). Biventricular mass was increased in obese compared with normal weight patients with right ventricular mass more affected than left ventricular mass. Obese patients demonstrated decreased biventricular end-diastolic volume (EDV) and stroke volume (SV) when indexed to body surface area (BSA) with an increased heart rate when compared with normal weight patients; cardiac index, ejection fraction, and pulmonary regurgitation fraction were similar. When indexed to ideal BSA, biventricular EDV and SV were similar. EDV and SV for overweight patients were nearly identical to normal weight patients with ventricular mass in between the other 2 groups. Approximately 12% of patients after TOF repair referred for cardiac magnetic resonance in a tertiary referral center are obese with increased biventricular mass. Obese patients and normal weight patients have similar cardiac indices, however, when indexed to actual BSA, obese patients demonstrate decreased EDV and SV with increased heart rate and similar cardiac indices. When indexed to ideal BSA, no differences in biventricular volumes were noted. Copyright © 2015. Published by Elsevier Inc.

N-linked glycosylation of SV2 is required for binding and uptake of botulinum neurotoxin A

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Yao, Guorui; Zhang, Sicai; Mahrhold, Stefan; Lam, Kwok-ho; Stern, Daniel; Bagramyan, Karine; Perry, Kay; Kalkum, Markus; Rummel, Andreas; Dong, Min; Jin, Rongsheng

2016-01-01

Botulinum neurotoxin serotype A1 (BoNT/A1) is one of the most dangerous potential bioterrorism agents, and exerts its action by invading motoneurons. It is also a licensed drug widely used for medical and cosmetic applications. Here we report a 2.0 Å resolution crystal structure of BoNT/A1 receptor-binding domain in complex with its neuronal receptor, the glycosylated human SV2C. We find that the neuronal tropism of BoNT/A1 requires recognition of both the peptide moiety and an N-linked glycan on SV2. This N-glycan—conserved in all SV2 isoforms across vertebrates—is essential for BoNT/A1 binding to neurons and its potent neurotoxicity. The glycan-binding interface on SV2 is targeted by a human BoNT/A1-neutralizing antibody currently licensed as an anti-botulism drug. Our studies reveal a new paradigm of host-pathogen interactions, in which pathogens exploit conserved host post-translational modifications to achieve highly specific receptor binding while also tolerating genetic changes across multiple isoforms of receptors. PMID:27294781

Knowledge of Stroke Risk Factors among Stroke Survivors in Nigeria

OpenAIRE

Grace Vincent-Onabajo; Taritei Moses

2016-01-01

Background. Knowledge of stroke risk factors is expected to reduce the incidence of stroke?whether first-ever or recurrent. This study examined knowledge of stroke risk factors and its determinants among stroke survivors. Methods. A cross-sectional survey of consenting stroke survivors at two physiotherapy facilities in Nigeria was carried out. Sociodemographic and clinical data were obtained and knowledge of stroke risk factors (defined as the ability to mention at least one correct risk fac...

Influence of heart motion on cardiac output estimation by means of electrical impedance tomography: a case study

International Nuclear Information System (INIS)

Proença, Martin; Braun, Fabian; Rapin, Michael; Solà, Josep; Lemay, Mathieu; Adler, Andy; Grychtol, Bartłomiej; Bohm, Stephan H; Thiran, Jean-Philippe

2015-01-01

Electrical impedance tomography (EIT) is a non-invasive imaging technique that can measure cardiac-related intra-thoracic impedance changes. EIT-based cardiac output estimation relies on the assumption that the amplitude of the impedance change in the ventricular region is representative of stroke volume (SV). However, other factors such as heart motion can significantly affect this ventricular impedance change. In the present case study, a magnetic resonance imaging-based dynamic bio-impedance model fitting the morphology of a single male subject was built. Simulations were performed to evaluate the contribution of heart motion and its influence on EIT-based SV estimation. Myocardial deformation was found to be the main contributor to the ventricular impedance change (56%). However, motion-induced impedance changes showed a strong correlation (r = 0.978) with left ventricular volume. We explained this by the quasi-incompressibility of blood and myocardium. As a result, EIT achieved excellent accuracy in estimating a wide range of simulated SV values (error distribution of 0.57 ± 2.19 ml (1.02 ± 2.62%) and correlation of r = 0.996 after a two-point calibration was applied to convert impedance values to millilitres). As the model was based on one single subject, the strong correlation found between motion-induced changes and ventricular volume remains to be verified in larger datasets. (paper)

Identification of stroke mimics among clinically diagnosed acute strokes.

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Tuntiyatorn, Lojana; Saksornchai, Pichaya; Tunlayadechanont, Supoch

2013-09-01

Stroke is a clinically syndrome of a sudden onset of neurological deficit in a vascular cause. Stroke mimics is the non-vascular disorders with stroke-like clinical symptoms. It is important to distinguish true stroke from mimics since treatment plan may differ To determine the incidence of the stroke mimics and identify their etiologies. All non-contrast head CT of the patients with clinically diagnosed stroke who immediately received imaging upon arrival at the emergency department of the university hospital were retrospectively reviewed in 12-month period between January 1 and December 31, 2008. Medical records, laboratory results, MRI, and 6-month clinical follow-up records were reviewed for final diagnosis. Seven hundred four patients were included in this study, including 363 (51.5%) men and 341 (48.5%) women with range in age from 24 to 108 years. Amongst those, 417 (59.2%) were ischemic stroke, 80 (11.40%) were hemorrhagic stroke, 186 (26.4%) were stroke-mimics, and 21 (3%) were inconclusive. The etiologies among stroke-mimics were metabolic/intoxication (35, 18.8%), sepsis (28, 15.0%), seizure (21, 11.3%), syncope (20, 10.8%), subdural hemorrhage (14, 7.5%), vertigo (11, 6.0%), brain tumor (10, 5.30%), central nervous system infection (5, 2.7%), others (26, 14.0%), and unspecified (16, 8.6%). Incidence rates and etiologies of the stroke mimics were similar to the western reports. However the frequency of each mimic was not.

Prevention Of Stroke

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Nagaraja D

2005-01-01

Full Text Available Stroke is an important cause for neurological morbidity and mortality. Prevention of ischemic stroke involves identification and prevention of risk factors and optimal use of pharmacotherapy. Risk factors have been classified as modifiable and non-modifiable; control of modifiable factors should prevent stroke occurrence. Stroke prevention has been described at three levels: primary, secondary and tertiary. Prolonged hypertension increases an individual′s risk for developing fatal or nonfatal stroke by three times and its control has been shown to prevent stroke. Diabetes mellitus is an important cause for microangiopathy and predisposes to stroke. Statin trials have shown significant reduction in stroke in those who were treated with statins. Stroke risk can be reduced by avoiding tobacco use, control of obesity and avoiding sedentary life style. Anti platelet medications are effective for secondary prevention of stroke. Educating society regarding modifiable risk factors and optimal use of pharmacotherapy form the cornerstone for the prevention of stroke.

Stroke risk perception among participants of a stroke awareness campaign

Science.gov (United States)

Kraywinkel, Klaus; Heidrich, Jan; Heuschmann, Peter U; Wagner, Markus; Berger, Klaus

2007-01-01

Background Subjective risk factor perception is an important component of the motivation to change unhealthy life styles. While prior studies assessed cardiovascular risk factor knowledge, little is known about determinants of the individual perception of stroke risk. Methods Survey by mailed questionnaire among 1483 participants of a prior public stroke campaign in Germany. Participants had been informed about their individual stroke risk based on the Framingham stroke risk score. Stroke risk factor knowledge, perception of lifetime stroke risk and risk factor status were included in the questionnaire, and the determinants of good risk factor knowledge and high stroke risk perception were identified using logistic regression models. Results Overall stroke risk factor knowledge was good with 67–96% of the participants recognizing established risk factors. The two exceptions were diabetes (recognized by 49%) and myocardial infarction (57%). Knowledge of a specific factor was superior among those affected by it. 13% of all participants considered themselves of having a high stroke risk, 55% indicated a moderate risk. All major risk factors contributed significantly to the perception of being at high stroke risk, but the effects of age, sex and education were non-significant. Poor self-rated health was additionally associated with high individual stroke risk perception. Conclusion Stroke risk factor knowledge was high in this study. The self perception of an increased stroke risk was associated with established risk factors as well as low perception of general health. PMID:17371603

Relative cerebral blood volume is associated with collateral status and infarct growth in stroke patients in SWIFT PRIME.

Science.gov (United States)

Arenillas, Juan F; Cortijo, Elisa; García-Bermejo, Pablo; Levy, Elad I; Jahan, Reza; Goyal, Mayank; Saver, Jeffrey L; Albers, Gregory W

2017-01-01

We aimed to evaluate how predefined candidate cerebral perfusion parameters correlate with collateral circulation status and to assess their capacity to predict infarct growth in patients with acute ischemic stroke (AIS) eligible for endovascular therapy. Patients enrolled in the SWIFT PRIME trial with baseline computed tomography perfusion (CTP) scans were included. RAPID software was used to calculate mean relative cerebral blood volume (rCBV) in hypoperfused regions, and hypoperfusion index ratio (HIR). Blind assessments of collaterals were performed using CT angiography in the whole sample and cerebral angiogram in the endovascular group. Reperfusion was assessed on 27-h CTP; infarct volume was assessed on 27-h magnetic resonance imaging/CT scans. Logistic and rank linear regression models were conducted. We included 158 patients. High rCBV ( p = 0.03) and low HIR ( p = 0.03) were associated with good collaterals. A positive association was found between rCBV and better collateral grades on cerebral angiography ( p = 0.01). Baseline and 27-h follow-up CTP were available for 115 patients, of whom 74 (64%) achieved successful reperfusion. Lower rCBV predicted a higher infarct growth in successfully reperfused patients ( p = 0.038) and in the endovascular treatment group ( p = 0.049). Finally, rCBV and HIR may serve as markers of collateral circulation in AIS patients prior to endovascular therapy. Unique identifier: NCT0165746.

Deteriorating ischaemic stroke. cytokines, soluble cytokine receptors, ferritin, systemic blood pressure, body temperature, blood glucose, diabetes, stroke severity, and CT infarction-volume as predictors of deteriorating ischaemic stroke

DEFF Research Database (Denmark)

Christensen, Hanne; Boysen, Gudrun; Johannesen, Helle Hjorth

2002-01-01

Although the causes of neurological deterioration in acute cerebral infarction have not yet been identified, many variables have been associated with deterioration. The aim of this study was to investigate deteriorating ischaemic stroke....

PSHA in Israel by using the synthetic ground motions from simulated seismicity: the modified SvE procedure

Science.gov (United States)

Meirova, T.; Shapira, A.; Eppelbaum, L.

2018-05-01

In this study, we updated and modified the SvE approach of Shapira and van Eck (Nat Hazards 8:201-215, 1993) which may be applied as an alternative to the conventional probabilistic seismic hazard assessment (PSHA) in Israel and other regions of low and moderate seismicity where measurements of strong ground motions are scarce. The new computational code SvE overcomes difficulties associated with the description of the earthquake source model and regional ground-motion scaling. In the modified SvE procedure, generating suites of regional ground motion is based on the extended two-dimensional source model of Motazedian and Atkinson (Bull Seism Soc Amer 95:995-1010, 2005a) and updated regional ground-motion scaling (Meirova and Hofstteter, Bull Earth Eng 15:3417-3436, 2017). The analytical approach of Mavroeidis and Papageorgiou (Bull Seism Soc Amer 93:1099-1131, 2003) is used to simulate the near-fault acceleration with the near-fault effects. The comparison of hazard estimates obtained by using the conventional method implemented in the National Building Code for Design provisions for earthquake resistance of structures and the modified SvE procedure for rock-site conditions indicates a general agreement with some perceptible differences at the periods of 0.2 and 0.5 s. For the periods above 0.5 s, the SvE estimates are systematically greater and can increase by a factor of 1.6. For the soft-soil sites, the SvE hazard estimates at the period of 0.2 s are greater than those based on the CB2008 ground-motion prediction equation (GMPE) by a factor of 1.3-1.6. We suggest that the hazard estimates for the sites with soft-soil conditions calculated by the modified SvE procedure are more reliable than those which can be found by means of the conventional PSHA. This result agrees with the opinion that the use of a standard GMPE applying the NEHRP soil classification based on the V s, 30 parameter may be inappropriate for PSHA at many sites in Israel.

Blood Pressure Control: Stroke and Stroke Prevention

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Hans-Christoph Diener

2005-03-01

Full Text Available Hypertension is the most important modifiable risk factor for primary and secondary stroke prevention.All antihypertensive drugs are effective in primary prevention: the risk reduction for stroke is 30—42%. However, not all classes of drugs have the same effects: there is some indication that angiotensin receptor blockers may be superior to other classes of antihypertensive drugs in stroke prevention.Seventy-five percent of patients who present to hospital with acute stroke have elevated blood pressure within the first 24—48 hours. Extremes of systolic blood pressure (SBP increase the risk of death or dependency. The aim of treatment should be to achieve and maintain the SBP in the range 140—160 mmHg. However, fast and drastic blood pressure lowering can have adverse consequences.The PROGRESS trial of secondary prevention with perindopril + indapamide versus placebo + placebo showed a decrease in numbers of stroke recurrences in patients given both active antihypertensive agents, more impressive for cerebral haemorrhage.There were also indications that active treatment might decrease the development of post-stroke dementia.

Hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation.

Science.gov (United States)

Marsh, E B; Llinas, R H; Hillis, A E; Gottesman, R F

2013-06-01

Intracerebral hemorrhage (ICH) can occur in patients following acute ischaemic stroke in the form of hemorrhagic transformation, and results in significant long-term morbidity and mortality. Anticoagulation theoretically increases risk. We evaluated stroke patients with an indication for anticoagulation to determine the factors associated with hemorrhagic transformation. Three-hundred and forty-five patients with ICD-9 codes indicating: (i) acute ischaemic stroke; and (ii) an indication for anticoagulation were screened. One-hundred and twenty-three met inclusion criteria. Data were collected retrospectively. Neuroimaging was reviewed for infarct volume and evidence of ICH. Hemorrhages were classified as: hemorrhagic conversion (petechiae) versus intracerebral hematoma (a space occupying lesion); symptomatic versus asymptomatic. Using multivariable logistic regression, we determined the hypothesized factors associated with intracerebral bleeding. Age [odds ratio (OR) = 1.50 per 10-year increment, 95% confidence interval (CI) 1.07-2.08], infarct volume (OR = 1.10 per 10 ccs, 95% CI 1.06-1.18) and worsening category of renal impairment by estimated glomerular filtration rate (eGFR; OR = 1.95, 95% CI 1.04-3.66) were predictors of hemorrhagic transformation. Ninety- nine out of 123 patients were anticoagulated. Hemorrhage rates of patients on and off anticoagulation did not differ (25.3% vs. 20.8%; P = 0.79); however, all intracerebral hematomas (n = 7) and symptomatic bleeds (n = 8) occurred in the anticoagulated group. The risk of hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation is multifactorial, and most closely associated with an individual's age, infarct volume and eGFR. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

Value of the regurgitant volume to end diastolic volume ratio to predict the regression of left ventricular dimensions after valve replacement in aortic insufficiency

NARCIS (Netherlands)

P.M. Fioretti (Paolo); C. Tirtaman; E. Bos (Egbert); P.W.J.C. Serruys (Patrick); J.R.T.C. Roelandt (Jos)

1987-01-01

textabstractThe aim of this study was to assess the value of regurgitant stroke volume (RSV) to end-diastolic volume (EDV) ratio to predict the regression of left ventricular (LV) dimensions after uncomplicated valve replacement in 34 patients with severe pure aortic insufficiency. The RSV/EDV ratio

Hemorrhagic and ischemic strokes compared: stroke severity, mortality, and risk factors.

Science.gov (United States)

Andersen, Klaus Kaae; Olsen, Tom Skyhøj; Dehlendorff, Christian; Kammersgaard, Lars Peter

2009-06-01

Stroke patients with hemorrhagic (HS) and ischemic strokes were compared with regard to stroke severity, mortality, and cardiovascular risk factors. A registry started in 2001, with the aim of registering all hospitalized stroke patients in Denmark, now holds information for 39,484 patients. The patients underwent an evaluation including stroke severity (Scandinavian Stroke Scale), CT, and cardiovascular risk factors. They were followed-up from admission until death or censoring in 2007. Independent predictors of death were identified by means of a survival model based on 25,123 individuals with a complete data set. Of the patients 3993 (10.1%) had HS. Stroke severity was almost linearly related to the probability of having HS (2% in patients with the mildest stroke and 30% in those with the most severe strokes). Factors favoring ischemic strokes vs HS were diabetes, atrial fibrillation, previous myocardial infarction, previous stroke, and intermittent arterial claudication. Smoking and alcohol consumption favored HS, whereas age, sex, and hypertension did not herald stroke type. Compared with ischemic strokes, HS was associated with an overall higher mortality risk (HR, 1.564; 95% CI, 1.441-1.696). The increased risk was, however, time-dependent; initially, risk was 4-fold, after 1 week it was 2.5-fold, and after 3 weeks it was 1.5-fold. After 3 months stroke type did not correlate to mortality. Strokes are generally more severe in patients with HS. Within the first 3 months after stroke, HS is associated with a considerable increase of mortality, which is specifically associated with the hemorrhagic nature of the lesion.

Early superoxide dismutase alterations during SV40-transformation of human fibroblasts.

Science.gov (United States)

Bravard, A; Hoffschir, F; Sabatier, L; Ricoul, M; Pinton, A; Cassingena, R; Estrade, S; Luccioni, C; Dutrillaux, B

1992-11-11

The expression of superoxide dismutases (SOD) 1 and 2 was studied in 4 clones of human fibroblasts after their infection by simian virus 40 (SV40), in parallel with the alterations of chromosomes 21 and chromosome 6q arms, carrying the genes that encode for SOD1 and SOD2 respectively. For all clones, a similar scheme with 2 main phases was observed for both chromosome and SOD variations. The first phase, defined as the pre-crisis phase, was characterized by chromosomal instability, but maintenance of normal numbers of chromosome 6q arms and chromosomes 21. The level of SOD2 mRNA was high, while SOD2 activity and immunoreactive protein were low. SOD1 protein and activity were decreased. In the second phase, defined as the post-crisis phase, the accumulation of clonal chromosomal rearrangements led to the loss of 6q arms, while the number of chromosomes 21 remained normal. SOD2 mRNA level was decreased and SOD2 immunoreactive protein and activity remained low. SOD1 protein and activity increased with passages, reaching values similar to those of control cells at late passages. As in established SV40-transformed human fibroblast cell lines, good correlation was found between SOD2 activity and the relative number of 6q arms. These results allow us to reconstruct the sequence of events leading to the decrease of SOD2, a possible tumor-suppressor gene, during the process of SV40-transformation of human fibroblasts.

Measurement Invariance of the Short Version of the Problematic Mobile Phone Use Questionnaire (PMPUQ-SV) across Eight Languages.

Science.gov (United States)

Lopez-Fernandez, Olatz; Kuss, Daria J; Pontes, Halley M; Griffiths, Mark D; Dawes, Christopher; Justice, Lucy V; Männikkö, Niko; Kääriäinen, Maria; Rumpf, Hans-Jürgen; Bischof, Anja; Gässler, Ann-Kathrin; Romo, Lucia; Kern, Laurence; Morvan, Yannick; Rousseau, Amélie; Graziani, Pierluigi; Demetrovics, Zsolt; Király, Orsolya; Schimmenti, Adriano; Passanisi, Alessia; Lelonek-Kuleta, Bernadeta; Chwaszcz, Joanna; Chóliz, Mariano; Zacarés, Juan José; Serra, Emilia; Dufour, Magali; Rochat, Lucien; Zullino, Daniele; Achab, Sophia; Landrø, Nils Inge; Suryani, Eva; Hormes, Julia M; Terashima, Javier Ponce; Billieux, Joël

2018-06-08

The prevalence of mobile phone use across the world has increased greatly over the past two decades. Problematic Mobile Phone Use (PMPU) has been studied in relation to public health and comprises various behaviours, including dangerous, prohibited, and dependent use. These types of problematic mobile phone behaviours are typically assessed with the short version of the Problematic Mobile Phone Use Questionnaire (PMPUQ⁻SV). However, to date, no study has ever examined the degree to which the PMPU scale assesses the same construct across different languages. The aims of the present study were to (i) determine an optimal factor structure for the PMPUQ⁻SV among university populations using eight versions of the scale (i.e., French, German, Hungarian, English, Finnish, Italian, Polish, and Spanish); and (ii) simultaneously examine the measurement invariance (MI) of the PMPUQ⁻SV across all languages. The whole study sample comprised 3038 participants. Descriptive statistics, correlations, and Cronbach's alpha coefficients were extracted from the demographic and PMPUQ-SV items. Individual and multigroup confirmatory factor analyses alongside MI analyses were conducted. Results showed a similar pattern of PMPU across the translated scales. A three-factor model of the PMPUQ-SV fitted the data well and presented with good psychometric properties. Six languages were validated independently, and five were compared via measurement invariance for future cross-cultural comparisons. The present paper contributes to the assessment of problematic mobile phone use because it is the first study to provide a cross-cultural psychometric analysis of the PMPUQ-SV.

Cerebral collateral therapeutics in acute ischemic stroke: A randomized preclinical trial of four modulation strategies.

Science.gov (United States)

Beretta, Simone; Versace, Alessandro; Carone, Davide; Riva, Matteo; Dell'Era, Valentina; Cuccione, Elisa; Cai, Ruiyao; Monza, Laura; Pirovano, Silvia; Padovano, Giada; Stiro, Fabio; Presotto, Luca; Paternò, Giovanni; Rossi, Emanuela; Giussani, Carlo; Sganzerla, Erik P; Ferrarese, Carlo

2017-10-01

Cerebral collaterals are dynamically recruited after arterial occlusion and highly affect tissue outcome in acute ischemic stroke. We investigated the efficacy and safety of four pathophysiologically distinct strategies for acute modulation of collateral flow (collateral therapeutics) in the rat stroke model of transient middle cerebral artery (MCA) occlusion. A composed randomization design was used to assign rats (n = 118) to receive phenylephrine (induced hypertension), polygeline (intravascular volume load), acetazolamide (cerebral arteriolar vasodilation), head down tilt (HDT) 15° (cerebral blood flow diversion), or no treatment, starting 30 min after MCA occlusion. Compared to untreated animals, treatment with collateral therapeutics was associated with lower infarct volumes (62% relative mean difference; 51.57 mm 3 absolute mean difference; p Collateral therapeutics acutely increased cerebral perfusion in the medial (+40.8%; p collaterals is feasible and provides a tissue-saving effect in the hyperacute phase of ischemic stroke prior to recanalization therapy.

Stroke Care 2: Stroke rehabilitation

NARCIS (Netherlands)

Langhorne, P.; Bernhardt, J.; Kwakkel, G.

2011-01-01

Stroke is a common, serious, and disabling global health-care problem, and rehabilitation is a major part of patient care. There is evidence to support rehabilitation in well coordinated multidisciplinary stroke units or through provision of early supported provision of discharge teams. Potentially

Airplane stroke syndrome.

Science.gov (United States)

Humaidan, Hani; Yassi, Nawaf; Weir, Louise; Davis, Stephen M; Meretoja, Atte

2016-07-01

Only 37 cases of stroke during or soon after long-haul flights have been published to our knowledge. In this retrospective observational study, we searched the Royal Melbourne Hospital prospective stroke database and all discharge summaries from 1 September 2003 to 30 September 2014 for flight-related strokes, defined as patients presenting with stroke within 14days of air travel. We hypothesised that a patent foramen ovale (PFO) is an important, but not the only mechanism, of flight-related stroke. We describe the patient, stroke, and flight characteristics. Over the study period, 131 million passengers arrived at Melbourne airport. Our centre admitted 5727 stroke patients, of whom 42 (0.73%) had flight-related strokes. Flight-related stroke patients were younger (median age 65 versus 73, p<0.001), had similar stroke severity, and received intravenous thrombolysis more often than non-flight-related stroke patients. Seven patients had flight-related intracerebral haemorrhage. The aetiology of the ischaemic strokes was cardioembolic in 14/35 (40%), including seven patients with confirmed PFO, one with atrial septal defect, four with atrial fibrillation, one with endocarditis, and one with aortic arch atheroma. Paradoxical embolism was confirmed in six patients. Stroke related to air travel is a rare occurrence, less than one in a million. Although 20% of patients had a PFO, distribution of stroke aetiologies was diverse and was not limited to PFO and paradoxical embolism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Predicting discharge destination after stroke: A systematic review.

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Mees, Margot; Klein, Jelle; Yperzeele, Laetitia; Vanacker, Peter; Cras, Patrick

2016-03-01

Different factors have been studied and proven to significantly influence discharge destination of acute stroke patients after hospitalization. Few reviews have been published combining the results of these studies. Therefore we aim to present an overview of the studies conducted regarding these predicting factors. Through conducting a systematic review we aimed to study the different predictive factors influencing discharge destination of acute stroke patients after hospitalization. Nineteen articles were selected in accordance with the research question and inclusion criteria. The factors found were, according to their significance in the articles, subcategorized in age, gender, functional status, cognitive status, race and ethnicity, co morbidities, education, stroke characteristics, social and living situation. The main factors significantly associated with other than home discharge were functional dependence/comorbidities, neurocognitive dysfunction and previous living circumstances/marital status. A medium or large infarct is associated with institutionalization. The stroke volume is not associated with home discharge. The effect of other factors remain controversial and results differ between studies. These include: age, gender, race, affected hemisphere and availability of a caregiver not living at home. Factors such as education, hospital complications, geographic location and FIM progression during hospitalization have not been studied sufficiently. Copyright © 2016 Elsevier B.V. All rights reserved.

Reported Prestroke Physical Activity Is Associated with Vascular Endothelial Growth Factor Expression and Good Outcomes after Stroke.

Science.gov (United States)

López-Cancio, Elena; Ricciardi, Ana Clara; Sobrino, Tomás; Cortés, Jordi; de la Ossa, Natalia Pérez; Millán, Mónica; Hernández-Pérez, María; Gomis, Meritxell; Dorado, Laura; Muñoz-Narbona, Lucía; Campos, Francisco; Arenillas, Juan F; Dávalos, Antoni

2017-02-01

Physical activity (PhA) prior to stroke has been associated with good outcomes after the ischemic insult, but there is scarce data on the involved molecular mechanisms. We studied consecutive acute ischemic stroke patients admitted to a single tertiary stroke center. Prestroke PhA was evaluated with the International Physical Activity Questionnaire (metabolic equivalent of minutes/week). We studied several circulating angiogenic and neurogenic factors at different time points: vascular endothelial growth factor (VEGF), granulocyte colony-stimulating factor (G-CSF), and brain-derived neurotrophic factor (BDNF) at admission, day 7, and at 3 months. We considered good functional outcome at 3 months (modified Rankin scale  ≤ 2) as primary end point, and final infarct volume as secondary outcome. We studied 83 patients with at least 2 time point serum determinations (mean age 69.6 years, median National Institutes of Health Stroke Scale 17 at admission). Patients more physically active before stroke had a significantly higher increment of serum VEGF on the seventh day when compared to less active patients. This increment was an independent predictor of good functional outcome at 3 months and was associated with smaller infarct volume in multivariate analyses adjusted for relevant covariates. We did not find independent associations of G-CSF or BDNF levels neither with level of prestroke PhA nor with stroke outcomes. Although there are probably more molecular mechanisms by which PhA exerts its beneficial effects in stroke outcomes, our observation regarding the potential role of VEGF is plausible and in line with previous experimental studies. Further research in this field is needed. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Association between baseline peri-infarct magnetic resonance spectroscopy and regional white matter atrophy after stroke

International Nuclear Information System (INIS)

Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew; Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M.; Churilov, Leonid; Donnan, Geoffrey A.; Parsons, Mark W.

2016-01-01

Cerebral atrophy after stroke is associated with poor functional outcome. The prediction and prevention of post-stroke brain atrophy could therefore represent a target for neurorestorative therapies. We investigated the associations between peri-infarct metabolite concentrations measured by quantitative MRS and brain volume change in the infarct hemisphere after stroke. Twenty patients with ischemic stroke were enrolled. Patients underwent 3T-MRI within 1 week of onset, and at 1 and 3 months. At the baseline scan, an MRS voxel was placed manually in the peri-infarct area and another in the corresponding contralateral region. Volumetric analysis of T1 images was performed using two automated processing packages. Changes in gray and white matter volume were assessed as percentage change between 1 and 3 months. Mean concentrations (institutional units) of N-acetylaspartic acid (NAA) (6.1 vs 7.0, p = 0.039), total creatine (Cr+PCr) (5.4 vs 5.8, p = 0.043), and inositol (4.5 vs 5.0, p = 0.014), were significantly lower in the peri-infarct region compared with the contralateral hemisphere. There was a significant correlation between baseline peri-infarct NAA and white matter volume change in the infarct hemisphere between 1 and 3 months, with lower NAA being associated with subsequent white matter atrophy (Spearman's rho = 0.66, p = 0.010). The baseline concentration of Cr+PCr was also significantly correlated with white matter atrophy in the infarct hemisphere (Spearman's rho = 0.59, p = 0.027). Both of these associations were significant after adjustment for the false discovery rate and were validated using the secondary volumetric method. MRS may be useful in the prediction of white matter atrophy post-stroke and in the testing of novel neurorestorative therapies. (orig.)

Association between baseline peri-infarct magnetic resonance spectroscopy and regional white matter atrophy after stroke

Energy Technology Data Exchange (ETDEWEB)

Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew [Melbourne Brain Centre rate at The Royal Melbourne Hospital, Departments of Medicine and Neurology, Parkville, Victoria (Australia); Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M. [The University of Melbourne, Department of Radiology, The Royal Melbourne Hospital, Parkville (Australia); Churilov, Leonid; Donnan, Geoffrey A. [The University of Melbourne, Florey Institute of Neuroscience and Mental Health, Parkville (Australia); Parsons, Mark W. [University of Newcastle and Hunter Medical Research Institute, Priority Research Centre for Translational Neuroscience and Mental Health, Newcastle (Australia)

2016-01-15

Cerebral atrophy after stroke is associated with poor functional outcome. The prediction and prevention of post-stroke brain atrophy could therefore represent a target for neurorestorative therapies. We investigated the associations between peri-infarct metabolite concentrations measured by quantitative MRS and brain volume change in the infarct hemisphere after stroke. Twenty patients with ischemic stroke were enrolled. Patients underwent 3T-MRI within 1 week of onset, and at 1 and 3 months. At the baseline scan, an MRS voxel was placed manually in the peri-infarct area and another in the corresponding contralateral region. Volumetric analysis of T1 images was performed using two automated processing packages. Changes in gray and white matter volume were assessed as percentage change between 1 and 3 months. Mean concentrations (institutional units) of N-acetylaspartic acid (NAA) (6.1 vs 7.0, p = 0.039), total creatine (Cr+PCr) (5.4 vs 5.8, p = 0.043), and inositol (4.5 vs 5.0, p = 0.014), were significantly lower in the peri-infarct region compared with the contralateral hemisphere. There was a significant correlation between baseline peri-infarct NAA and white matter volume change in the infarct hemisphere between 1 and 3 months, with lower NAA being associated with subsequent white matter atrophy (Spearman's rho = 0.66, p = 0.010). The baseline concentration of Cr+PCr was also significantly correlated with white matter atrophy in the infarct hemisphere (Spearman's rho = 0.59, p = 0.027). Both of these associations were significant after adjustment for the false discovery rate and were validated using the secondary volumetric method. MRS may be useful in the prediction of white matter atrophy post-stroke and in the testing of novel neurorestorative therapies. (orig.)

Acute stroke: automatic perfusion lesion outlining using level sets.

Science.gov (United States)

Mouridsen, Kim; Nagenthiraja, Kartheeban; Jónsdóttir, Kristjana Ýr; Ribe, Lars R; Neumann, Anders B; Hjort, Niels; Østergaard, Leif

2013-11-01

To develop a user-independent algorithm for the delineation of hypoperfused tissue on perfusion-weighted images and evaluate its performance relative to a standard threshold method in simulated data, as well as in acute stroke patients. The study was approved by the local ethics committee, and patients gave written informed consent prior to their inclusion in the study. The algorithm identifies hypoperfused tissue in mean transit time maps by simultaneously minimizing the mean square error between individual and mean perfusion values inside and outside a smooth boundary. In 14 acute stroke patients, volumetric agreement between automated outlines and manual outlines determined in consensus among four neuroradiologists was assessed with Bland-Altman analysis, while spatial agreement was quantified by using lesion overlap relative to mean lesion volume (Dice coefficient). Performance improvement relative to a standard threshold approach was tested with the Wilcoxon signed rank test. The mean difference in lesion volume between automated outlines and manual outlines was -9.0 mL ± 44.5 (standard deviation). The lowest mean volume difference for the threshold approach was -25.8 mL ± 88.2. A significantly higher Dice coefficient was observed with the algorithm (0.71; interquartile range [IQR], 0.42-0.75) compared with the threshold approach (0.50; IQR, 0.27- 0.57; P , .001). The corresponding agreement among experts was 0.79 (IQR, 0.69-0.83). The perfusion lesions outlined by the automated algorithm agreed well with those defined manually in consensus by four experts and were superior to those obtained by using the standard threshold approach. This user-independent algorithm may improve the assessment of perfusion images as part of acute stroke treatment. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13121622/-/DC1. RSNA, 2013

Stroke Rehabilitation.

Science.gov (United States)

Belagaje, Samir R

2017-02-01

Rehabilitation is an important aspect of the continuum of care in stroke. With advances in the acute treatment of stroke, more patients will survive stroke with varying degrees of disability. Research in the past decade has expanded our understanding of the mechanisms underlying stroke recovery and has led to the development of new treatment modalities. This article reviews and summarizes the key concepts related to poststroke recovery. Good data now exist by which one can predict recovery, especially motor recovery, very soon after stroke onset. Recent trials have not demonstrated a clear benefit associated with very early initiation of rehabilitative therapy after stroke in terms of improvement in poststroke outcomes. However, growing evidence suggests that shorter and more frequent sessions of therapy can be safely started in the first 24 to 48 hours after a stroke. The optimal amount or dose of therapy for stroke remains undetermined, as more intensive treatments have not been associated with better outcomes compared to standard intensities of therapy. Poststroke depression adversely affects recovery across a variety of measures and is an important target for therapy. Additionally, the use of selective serotonin reuptake inhibitors (SSRIs) appears to benefit motor recovery through pleiotropic mechanisms beyond their antidepressant effect. Other pharmacologic approaches also appear to have a benefit in stroke rehabilitation. A comprehensive rehabilitation program is essential to optimize poststroke outcomes. Rehabilitation is a process that uses three major principles of recovery: adaptation, restitution, and neuroplasticity. Based on these principles, multiple different approaches, both pharmacologic and nonpharmacologic, exist to enhance rehabilitation. In addition to neurologists, a variety of health care professionals are involved in stroke rehabilitation. Successful rehabilitation involves understanding the natural history of stroke recovery and a

Relationship Between Collateral Status, Contrast Transit, and Contrast Density in Acute Ischemic Stroke.

Science.gov (United States)

Kawano, Hiroyuki; Bivard, Andrew; Lin, Longting; Spratt, Neil J; Miteff, Ferdinand; Parsons, Mark W; Levi, Christopher R

2016-03-01

Collateral circulation is recognized to influence the life expectancy of the ischemic penumbra in acute ischemic stroke. The best method to quantify collateral status on acute imaging is uncertain. We aimed to determine the relationship between visual collateral status, quantitative collateral assessments, baseline computed tomographic perfusion measures, and tissue outcomes on follow-up imaging. Sixty-six consecutive patients with acute ischemic stroke clinically eligible for recanalization therapy and with M1 or M2 middle cerebral artery occlusion were evaluated. We compared the visual collateral scoring with measures of contrast peak time delay and contrast peak density. We also compared these measures for their ability to predict perfusion lesion and infarct core volumes, final infarct, and infarct growth. Shorter contrast peak time delay (P=0.041) and higher contrast peak density (P=0.002) were associated with good collateral status. Shorter contrast peak time delay correlated with higher contrast peak density (β=-4.413; P=0.037). In logistic regression analysis after adjustment for age, sex, onset-computed tomographic time, and occlusion site, higher contrast peak density was independently associated with good collateral status (P=0.009). Multiple regression analysis showed that higher contrast peak density was an independent predictor of smaller perfusion lesion volume (P=0.029), smaller ischemic core volume (P=0.044), smaller follow-up infarct volume (P=0.005), and smaller infarct growth volume (P=0.010). Visual collateral status, contrast peak density, and contrast peak time delay were inter-related, and good collateral status was strongly associated with contrast peak density. Contrast peak density in collateral vessel may be an important factor in tissue fate in acute ischemic stroke. © 2016 American Heart Association, Inc.

Ethnic differences in ischemic stroke subtypes in young-onset stroke: the Stroke Prevention in Young Adults Study.

Science.gov (United States)

Trivedi, Megh M; Ryan, Kathleen A; Cole, John W

2015-10-29

Prior studies indicate that young African-Americans (AA) have a greater frequency of ischemic stroke than similarly aged European-Americans (EA). We hypothesized that differences in stroke subtype frequency mediated through sex and differing risk factor profiles may play a role in ethnicity-specific stroke. Utilizing our biracial young-onset stroke population, we explored these relationships. Fifty nine hospitals in the Baltimore-Washington area participated in a population-based study of young-onset stroke in men (218-AA, 291-EA) and women (219-AA, 222-EA) aged 16-49. Data on age, sex, ethnicity and stroke risk factors (hypertension (HTN) and smoking) were gathered through standardized interview. A pair of vascular neurologists adjudicated each case to determine TOAST subtype. Logistic regression analyses evaluating for differences in stroke risk factors by TOAST subtype were performed. Analyses controlling for age and sex demonstrated that AA were more likely to have a lacunar stroke than EA (OR = 1.61; 95% CI = 1.12-2.32; p = 0.011) when utilizing the other TOAST subtypes as the reference group. This effect was mediated by HTN, which increases the risk of lacunar stroke (OR = 2.03; 95% CI = 1.38-2.98; p = 0.0003) and large artery stroke (OR = 1.70; 95% CI = 1.01-2.88; p = 0.048) when controlling for sex, ethnicity, and age. Cases below age 40 were more likely to have a cardioembolic stroke than those above age 40 (OR = 1.62; 95% CI = 1.15-2.27; p = 0.006), controlling for sex and ethnicity. Lastly, current smokers were more likely to have a large artery stroke than non-smokers (OR = 1.79; 95% CI = 1.08-2.98; p = 0.024). Our population-based data demonstrate ethnic differences in ischemic stroke subtypes. These findings may help clarify mechanisms of stroke in young adults which may in part be driven by ethnic-specific differences in early-onset traditional risk factors, thereby indicating differing emphasis on workup and prevention.

Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

Energy Technology Data Exchange (ETDEWEB)

Su, L.-N.; Little, J.B. (Harvard School of Public Health, Boston, MA (United States))

1992-08-01

Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author).

Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

International Nuclear Information System (INIS)

Su, L.-N.; Little, J.B.

1992-01-01

Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author)

METABOLIC THERAPY IN PATIENTS WITH ISCHEMIC STROKE

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L. B. Zavaliy

2018-01-01

Full Text Available The article shows the world experience of metabolic therapy use in the treatment of ischemic stroke. The issue still remains prominent. The reasonability of prescribing metabolic drugs is not completely clear, its effectiveness has not been fully proved, despite numerous studies which show only trends. The article presents an overview of the most popular drugs of different pharmacological groups with a metabolic effect which affect different parts of the ischemic cascade. Ethylmethylhydroxypyridine succinate and cytoflavin have predominantly antihypoxic effect, improve functional outcome and neurological functions, and normalize overall well-being and adaptation. Cerebrolysin is a complex of low molecular weight biologically active peptides derived from the pig’s brain. It has a multimodal effect on the brain, helps to reduce the volume of cerebral infarction, restores neurologic functions and improves the functional outcome. Cortexin is a mixture of cattle brain polypeptides, also has a complex action that provides the most complete reversion of neurological deficit, improves cognitive functions and the functional outcome, reduces the level of paroxysmal convulsive readiness and improves bioelectric activity of the brain. Citicoline is a precursor of cell membrane key ultrastructures, contributes to significant reduction in the volume of cortical brain damage, improves cholinergic transmission, which results in better clinical outcome, even despite the questionable impact on the neurological status. Choline Alfoscerate is a precursor of choline, and the use of the drug significantly limits the growth of the cerebral infarction area starting from the first day of therapy, leads to reversion of neurological symptoms and achievement of rehabilitation goals. Actovegin is deproteinized derivative of calf blood, activates metabolism in tissues, improves trophism and stimulates regeneration. In a large study, it was shown that Actovegin improved

Effects of radiation dose reduction in Volume Perfusion CT imaging of acute ischemic stroke

International Nuclear Information System (INIS)

Othman, Ahmed E.; Brockmann, Carolin; Afat, Saif; Pjontek, Rastislav; Nikobashman, Omid; Brockmann, Marc A.; Wiesmann, Martin; Yang, Zepa; Kim, Changwon; Kim, Jong Hyo

2015-01-01

To examine the influence of radiation dose reduction on image quality and sensitivity of Volume Perfusion CT (VPCT) maps regarding the detection of ischemic brain lesions. VPCT data of 20 patients with suspected ischemic stroke acquired at 80 kV and 180 mAs were included. Using realistic reduced-dose simulation, low-dose VPCT datasets with 144 mAs, 108 mAs, 72 mAs and 36 mAs (80 %, 60 %, 40 % and 20 % of the original levels) were generated, resulting in a total of 100 datasets. Perfusion maps were created and signal-to-noise-ratio (SNR) measurements were performed. Qualitative analyses were conducted by two blinded readers, who also assessed the presence/absence of ischemic lesions and scored CBV and CBF maps using a modified ASPECTS-score. SNR of all low-dose datasets were significantly lower than those of the original datasets (p <.05). All datasets down to 72 mAs (40 %) yielded sufficient image quality and high sensitivity with excellent inter-observer-agreements, whereas 36 mAs datasets (20 %) yielded poor image quality in 15 % of the cases with lower sensitivity and inter-observer-agreements. Low-dose VPCT using decreased tube currents down to 72 mAs (40 % of original radiation dose) produces sufficient perfusion maps for the detection of ischemic brain lesions. (orig.)

Outcome Determinants of Stroke in a Brazilian Primary Stroke Center

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Gustavo W. Kuster

2014-01-01

Full Text Available Background. Stroke mortality in Brazil is one of the highest among Western countries. Nonetheless, stroke outcome determinants are still poorly known in this country. In this study we evaluate outcome determinants of stroke in a primary stroke center in São Paulo, Brazil. Methods. We evaluated demographic, clinical, and outcome data of patients with ischemic stroke (IS, transient ischemic attack (TIA, and intracerebral hemorrhage (ICH admitted at “Hospital Paulistano,” São Paulo, Brazil. In-hospital mortality and functional outcome determinants were assessed. Univariate and binary logistic regression analysis were performed. Results. Three hundred forty-one patients were included in the study, 52.2% being male with 66.8±15.7 years. The stroke type distribution was IS: 59.2%, TIA: 29.6%, and ICH: 11.1%. ICH was associated with greater severity and poorer functional outcome. The determinants of poorer functional outcome were higher NIHSS, lower Glasgow score, and lower oxygen saturation level. The most important mortality determinant was the presence of visual symptoms. Conclusions. The stroke mortality and stroke outcome determinants found in the present study do not remarkably differ from studies carried out in developed countries. Stroke prognosis studies are crucial to better understand the high burden of stroke in Brazil.

Measurement Invariance of the Short Version of the Problematic Mobile Phone Use Questionnaire (PMPUQ-SV across Eight Languages

Directory of Open Access Journals (Sweden)

Olatz Lopez-Fernandez

2018-06-01

Full Text Available The prevalence of mobile phone use across the world has increased greatly over the past two decades. Problematic Mobile Phone Use (PMPU has been studied in relation to public health and comprises various behaviours, including dangerous, prohibited, and dependent use. These types of problematic mobile phone behaviours are typically assessed with the short version of the Problematic Mobile Phone Use Questionnaire (PMPUQ–SV. However, to date, no study has ever examined the degree to which the PMPU scale assesses the same construct across different languages. The aims of the present study were to (i determine an optimal factor structure for the PMPUQ–SV among university populations using eight versions of the scale (i.e., French, German, Hungarian, English, Finnish, Italian, Polish, and Spanish; and (ii simultaneously examine the measurement invariance (MI of the PMPUQ–SV across all languages. The whole study sample comprised 3038 participants. Descriptive statistics, correlations, and Cronbach’s alpha coefficients were extracted from the demographic and PMPUQ-SV items. Individual and multigroup confirmatory factor analyses alongside MI analyses were conducted. Results showed a similar pattern of PMPU across the translated scales. A three-factor model of the PMPUQ-SV fitted the data well and presented with good psychometric properties. Six languages were validated independently, and five were compared via measurement invariance for future cross-cultural comparisons. The present paper contributes to the assessment of problematic mobile phone use because it is the first study to provide a cross-cultural psychometric analysis of the PMPUQ-SV.

Usefulness of perfusion MR imaging in hyperacute ischemic stroke

International Nuclear Information System (INIS)

Park, Ji Hoon; Kim, Jae Hyoung; Shin, Tae Min; Lee, Eun Ja; Chung, Sung Hoon; Choi, Nack Cheon; Lim, Byeong Hoon; Kim, In One

1998-01-01

Perfusion MR imaging is a new technique for the assessment of acute ischemic stroke. The aim of this study was to evaluate the usefulness of this imaging in hyperacute ischemic stroke in comparison with conventional CT and MR imaging. Eight patients presenting the symptoms of acute ischemic stroke due to middle cerebral artery occlusion were included in this study. Within 2 hours of initial CT scan and 6 hours after the onset of stroke, perfusion MR imaging was performed in all patients using a single-section dynamic contrast-enhanced T2*-weighted imager in conjunction with conventional routine MR imaging and MR angiography. Cerebral blood volume (CBV) maps were then obtained from dynamic MR imaging data by using numerical integration techniques. The findings of CBV maps were compared with those of initial and follow-up CT or MR images. The findings of CBV maps were obviously abnormal in all patients, as compared with normal or focal subtle abnormal findings seen on initial CT and MR images. CBV in the occluded arterial territory was lower in all eight patients;two had focal regions of increased CBV within the affected territory, indicating reperfusion hyperemia. In all patients, regions of abnormal CBV were eventually converted to infarctions on follow-up images. Perfusion MR imaging was useful for the evaluation of hemodynamic change occurring during cerebral perfusion in hyperacute ischemic stroke, and prediction of the final extent of infarction. These results suggest that pertusion MR imaging can play an important role in the diagnosis and management of hyperacute ischemic stroke.=20

Automation of CT-based haemorrhagic stroke assessment for improved clinical outcomes: study protocol and design.

Science.gov (United States)

Chinda, Betty; Medvedev, George; Siu, William; Ester, Martin; Arab, Ali; Gu, Tao; Moreno, Sylvain; D'Arcy, Ryan C N; Song, Xiaowei

2018-04-19

Haemorrhagic stroke is of significant healthcare concern due to its association with high mortality and lasting impact on the survivors' quality of life. Treatment decisions and clinical outcomes depend strongly on the size, spread and location of the haematoma. Non-contrast CT (NCCT) is the primary neuroimaging modality for haematoma assessment in haemorrhagic stroke diagnosis. Current procedures do not allow convenient NCCT-based haemorrhage volume calculation in clinical settings, while research-based approaches are yet to be tested for clinical utility; there is a demonstrated need for developing effective solutions. The project under review investigates the development of an automatic NCCT-based haematoma computation tool in support of accurate quantification of haematoma volumes. Several existing research methods for haematoma volume estimation are studied. Selected methods are tested using NCCT images of patients diagnosed with acute haemorrhagic stroke. For inter-rater and intrarater reliability evaluation, different raters will analyse haemorrhage volumes independently. The efficiency with respect to time of haematoma volume assessments will be examined to compare with the results from routine clinical evaluations and planimetry assessment that are known to be more accurate. The project will target the development of an enhanced solution by adapting existing methods and integrating machine learning algorithms. NCCT-based information of brain haemorrhage (eg, size, volume, location) and other relevant information (eg, age, sex, risk factor, comorbidities) will be used in relation to clinical outcomes with future project development. Validity and reliability of the solution will be examined for potential clinical utility. The project including procedures for deidentification of NCCT data has been ethically approved. The study involves secondary use of existing data and does not require new consent of participation. The team consists of clinical neuroimaging

Atherosclerosis and Stroke

Science.gov (United States)

... Stroke Association.org Professionals for Stroke Association.org Shop for Stroke Association.org Support for Stroke Association. ... endothelium significantly. The artery’s diameter shrinks and blood flow decreases, reducing oxygen supply. How atherosclerotic plaque causes ...

Hemorrhagic and Ischemic Strokes Compared Stroke Severity, Mortality, and Risk Factors

DEFF Research Database (Denmark)

Andersen, Klaus Kaae; Olsen, T. S.; Dehlendorff, Christian

2009-01-01

were diabetes, atrial fibrillation, previous myocardial infarction, previous stroke, and intermittent arterial claudication. Smoking and alcohol consumption favored HS, whereas age, sex, and hypertension did not herald stroke type. Compared with ischemic strokes, HS was associated with an overall...... higher mortality risk (HR, 1.564; 95% CI, 1.441-1.696). The increased risk was, however, time-dependent; initially, risk was 4-fold, after 1 week it was 2.5-fold, and after 3 weeks it was 1.5-fold. After 3 months stroke type did not correlate to mortality. Conclusion-Strokes are generally more severe...... based on 25 123 individuals with a complete data set. Results-Of the patients 3993 (10.1%) had HS. Stroke severity was almost linearly related to the probability of having HS (2% in patients with the mildest stroke and 30% in those with the most severe strokes). Factors favoring ischemic strokes vs HS...

Neuroanatomic correlates of stroke-related myocardial injury.

Science.gov (United States)

Ay, H; Koroshetz, W J; Benner, T; Vangel, M G; Melinosky, C; Arsava, E M; Ayata, C; Zhu, M; Schwamm, L H; Sorensen, A G

2006-05-09

Myocardial injury can occur after ischemic stroke in the absence of primary cardiac causes. The neuroanatomic basis of stroke-related myocardial injury is not well understood. To identify regions of brain infarction associated with myocardial injury using a method free of the bias of an a priori hypothesis as to any specific location. Of 738 consecutive patients with acute ischemic stroke, the authors identified 50 patients in whom serum cardiac troponin T (cTnT) elevation occurred in the absence of any apparent cause within 3 days of symptom onset. Fifty randomly selected, age- and sex-matched patients with ischemic stroke without cTnT elevation served as controls. Diffusion-weighted images with outlines of infarction were co-registered to a template, averaged, and then subtracted to find voxels that differed between the two groups. Voxel-wise p values were determined using a nonparametric permutation test to identify specific regions of infarction that were associated with cTnT elevation. The study groups were well balanced with respect to stroke risk factors, history of coronary artery disease, infarction volume, and frequency of right and left middle cerebral artery territory involvement. Brain regions that were a priori associated with cTnT elevation included the right posterior, superior, and medial insula and the right inferior parietal lobule. Among patients with right middle cerebral artery infarction, the insular cluster was involved in 88% of patients with and 33% without cTnT elevation (odds ratio: 15.00; 95% CI: 2.65 to 84.79). Infarctions in specific brain regions including the right insula are associated with elevated serum cardiac troponin T level indicative of myocardial injury.

Stroke treatment outcomes in hospitals with and without Stroke Units.

Science.gov (United States)

Masjuan, J; Gállego Culleré, J; Ignacio García, E; Mira Solves, J J; Ollero Ortiz, A; Vidal de Francisco, D; López-Mesonero, L; Bestué, M; Albertí, O; Acebrón, F; Navarro Soler, I M

2017-10-23

Organisational capacity in terms of resources and care circuits to shorten response times in new stroke cases is key to obtaining positive outcomes. This study compares therapeutic approaches and treatment outcomes between traditional care centres (with stroke teams and no stroke unit) and centres with stroke units. We conducted a prospective, quasi-experimental study (without randomisation of the units analysed) to draw comparisons between 2 centres with stroke units and 4 centres providing traditional care through the neurology department, analysing a selection of agreed indicators for monitoring quality of stroke care. A total of 225 patients participated in the study. In addition, self-administered questionnaires were used to collect patients' evaluations of the service and healthcare received. Centres with stroke units showed shorter response times after symptom onset, both in the time taken to arrive at the centre and in the time elapsed from patient's arrival at the hospital to diagnostic imaging. Hospitals with stroke units had greater capacity to respond through the application of intravenous thrombolysis than centres delivering traditional neurological care. Centres with stroke units showed a better fit to the reference standards for stroke response time, as calculated in the Quick study, than centres providing traditional care through the neurology department. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Effektregnskab for projektet Digitales ll – Det svære valg

DEFF Research Database (Denmark)

Mark, Stine

Effektregnskabet for projektet Digitales ll – Det svære valg er udarbejdet af forskningscenteret INCEVIDA, Aalborg Universitet 2012. Rapporten er gennemført i et samarbejde mellem INCEVIDA, KulturarvNord og Bangsbo Museum. Effektregnskabet tager udgangspunkt i en model for oplevelsesøkonomisk...

Exhaust emissions of low level blend alcohol fuels from two-stroke and four-stroke marine engines

Science.gov (United States)

Sevik, James M., Jr.

The U.S. Renewable Fuel Standard mandates that by 2022, 36 billion gallons of renewable fuels must be produced on a yearly basis. Ethanol production is capped at 15 billion gallons, meaning 21 billion gallons must come from different alternative fuel sources. A viable alternative to reach the remainder of this mandate is iso-butanol. Unlike ethanol, iso-butanol does not phase separate when mixed with water, meaning it can be transported using traditional pipeline methods. Iso-butanol also has a lower oxygen content by mass, meaning it can displace more petroleum while maintaining the same oxygen concentration in the fuel blend. This research focused on studying the effects of low level alcohol fuels on marine engine emissions to assess the possibility of using iso-butanol as a replacement for ethanol. Three marine engines were used in this study, representing a wide range of what is currently in service in the United States. Two four-stroke engine and one two-stroke engine powered boats were tested in the tributaries of the Chesapeake Bay, near Annapolis, Maryland over the course of two rounds of weeklong testing in May and September. The engines were tested using a standard test cycle and emissions were sampled using constant volume sampling techniques. Specific emissions for two-stroke and four-stroke engines were compared to the baseline indolene tests. Because of the nature of the field testing, limited engine parameters were recorded. Therefore, the engine parameters analyzed aside from emissions were the operating relative air-to-fuel ratio and engine speed. Emissions trends from the baseline test to each alcohol fuel for the four-stroke engines were consistent, when analyzing a single round of testing. The same trends were not consistent when comparing separate rounds because of uncontrolled weather conditions and because the four-stroke engines operate without fuel control feedback during full load conditions. Emissions trends from the baseline test to each

White matter hyperintensity and stroke lesion segmentation and differentiation using convolutional neural networks

Directory of Open Access Journals (Sweden)

R. Guerrero

2018-01-01

Full Text Available White matter hyperintensities (WMH are a feature of sporadic small vessel disease also frequently observed in magnetic resonance images (MRI of healthy elderly subjects. The accurate assessment of WMH burden is of crucial importance for epidemiological studies to determine association between WMHs, cognitive and clinical data; their causes, and the effects of new treatments in randomized trials. The manual delineation of WMHs is a very tedious, costly and time consuming process, that needs to be carried out by an expert annotator (e.g. a trained image analyst or radiologist. The problem of WMH delineation is further complicated by the fact that other pathological features (i.e. stroke lesions often also appear as hyperintense regions. Recently, several automated methods aiming to tackle the challenges of WMH segmentation have been proposed. Most of these methods have been specifically developed to segment WMH in MRI but cannot differentiate between WMHs and strokes. Other methods, capable of distinguishing between different pathologies in brain MRI, are not designed with simultaneous WMH and stroke segmentation in mind. Therefore, a task specific, reliable, fully automated method that can segment and differentiate between these two pathological manifestations on MRI has not yet been fully identified. In this work we propose to use a convolutional neural network (CNN that is able to segment hyperintensities and differentiate between WMHs and stroke lesions. Specifically, we aim to distinguish between WMH pathologies from those caused by stroke lesions due to either cortical, large or small subcortical infarcts. The proposed fully convolutional CNN architecture, called uResNet, that comprised an analysis path, that gradually learns low and high level features, followed by a synthesis path, that gradually combines and up-samples the low and high level features into a class likelihood semantic segmentation. Quantitatively, the proposed CNN

Stroke: advances in medical therapy and acute stroke intervention.

Science.gov (United States)

Barrett, Kevin M; Lal, Brajesh K; Meschia, James F

2015-10-01

Evidence-based therapeutic options for stroke continue to emerge based on results from well-designed clinical studies. Ischemic stroke far exceeds hemorrhagic stroke in terms of prevalence and incidence, both in the USA and worldwide. The public health effect of reducing death and disability related to ischemic stroke justifies the resources that have been invested in identifying safe and effective treatments. The emergence of novel oral anticoagulants for ischemic stroke prevention in atrial fibrillation has introduced complexity to clinical decision making for patients with this common cardiac arrhythmia. Some accepted ischemic stroke preventative strategies, such as carotid revascularization for asymptomatic carotid stenosis, require reassessment, given advances in risk factor management, antithrombotic therapy, and surgical techniques. Intra-arterial therapy, particularly with stent retrievers after intravenous tissue plasminogen activator, has recently been demonstrated to improve functional outcomes and will require investment in system-based care models to ensure that effective treatments are received by patients in a timely fashion. The purpose of this review is to describe recent advances in medical and surgical approaches to ischemic stroke prevention and acute treatment. Results from recently published clinical trials will be highlighted along with ongoing clinical trials addressing key questions in ischemic stroke management and prevention where equipoise remains.

SV40 large T-p53 complex: evidence for the presence of two immunologically distinct forms of p53

International Nuclear Information System (INIS)

Milner, J.; Gamble, J.

1985-01-01

The transforming protein of SV40 is the large T antigen. Large T binds a cellular protein, p53, which is potentially oncogenic by virtue of its functional involvement in the control of cell proliferation. This raises the possibility that p53 may mediate, in part, the transforming function of SV40 large T. Two immunologically distinct forms of p53 have been identified in normal cells: the forms are cell-cycle dependent, one being restricted to nondividing cells (p53-Go) and the second to dividing cells (p53-G divided by). The authors have now dissociated and probed the multimeric complex of SV40 large T-p53 for the presence of immunologically distinct forms of p53. Here they present evidence for the presence of p53-Go and p53-G divided by complexed with SV40 large T

Long-term deficits in episodic memory after ischemic stroke: evaluation and prediction of verbal and visual memory performance based on lesion characteristics

NARCIS (Netherlands)

Schouten, Eveline A.; Schiemanck, Sven K.; Brand, Nico; Post, Marcel W. M.

2009-01-01

We investigated the relationship between ischemic lesion characteristics (hemispheric side, cortical and subcortical level, volume) and memory performance, 1 year after stroke. Verbal and visual memory of 86 patients with stroke were assessed with Rey Auditory-Verbal Learning Test and the Doors

Cardiac output and performance during a marathon race in middle-aged recreational runners.

Science.gov (United States)

Billat, Véronique L; Petot, Hélène; Landrain, Morgan; Meilland, Renaud; Koralsztein, Jean Pierre; Mille-Hamard, Laurence

2012-01-01

Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maximal laboratory test and then during a real marathon race (mean performance: 3 hr 30 min ± 45 min). Our data revealed that HR, SV and CO were all in a high but submaximal steady state during the marathon (87.0 ± 1.6%, 77.2 ± 2.6%, and 68.7 ± 2.8% of maximal values, respectively). Marathon performance was inversely correlated with an upward drift in the CO/speed ratio (mL of CO × m(-1)) (r = -0.65, P marathon performance is inversely correlated with cardiac cost and positively correlated with cardiac endurance. The CO response could be a benchmark for race performance in recreational marathon runners.

Inhibition of in vitro SV40 DNA replication by ultraviolet light

International Nuclear Information System (INIS)

Gough, G.; Wood, R.W.

1989-01-01

Ultraviolet light-induced DNA damage was found to inhibit SV40 origin-dependent DNA synthesis carried out by soluble humancell extracts. Replication of SV40-based plasmids was reduced to approx. 35% of that in unirradiated controls after irradiation with 50-100 J/m 2 germicidal ultraviolet light, where an average of 3-6 pyrimidine dimer photoproducts were formed per plasmid circle. Inhibition of the DNA helicase activity of T antigen (required for initiation of replication in the in vitro system) was also investigated, and was only significant after much higher fluences, 1000-5000 J/m 2 . The data indicate that DNA damage by ultraviolet light inhibits DNA synthesis in cell-free extracts principally by affecting components of the replication complex other than the DNA helicase activity of T antigen. The soluble system could be used to biochemically investigate the possible bypass or tolerance of DNA damage during replication (author). 21 refs.; 2 figs

Accuracy of the detection of infratentorial stroke lesions using perfusion CT: an experimenter-blinded study

Energy Technology Data Exchange (ETDEWEB)

Lee, In Hyouk; Kim, Myung Soon; Kim, Young Ju; Lee, Myeong Sub [Yonsei University, Department of Radiology, Wonju College of Medicine, Wonju (Korea, Republic of); You, Joshua H. [Center for Health, Wellness, Fitness, Prevention, and Healing Across the Life Span, Department of Physical Therapy, Graduate School of Rehabilitation Science, Yonsei University, Center for Movement Impairment Solutions, Wonju City (Korea, Republic of); Lee, Ji Yong [Yonsei University, Department of Neurology, Wonju College of Medicine, Wonju (Korea, Republic of); Whang, Kum [Yonsei University, Department of Neurosurgery, Wonju College of Medicine, Wonju (Korea, Republic of)

2010-12-15

Although perfusion CT (PCT) for the detection of supratentorial stroke is well established, there is a dearth of evidence of its effectiveness in the detection of infratentorial stroke. Hence, this study compared sensitivity, specificity, and accuracy of PCT maps between infratentorial and supratentorial stroke lesions. One hundred patients with acute stroke who had successfully undergone near whole-brain PCT with the toggling table technique and follow-up MRI were included. Wilcoxon Mann-Whitney test was performed at P < 0.01. There was no significant statistical difference in the accuracy (91.79% vs. 93.23% in regional cerebral blood volume; 92.26% vs. 95.31% in regional cerebral blood flow; 89.17% vs. 92.71% in mean transit time; 89.76% vs. 92.19% in time to peak; P > 0.01 in all PCT maps) between supratentorial and infratentorial stroke. Also, there was no remarkable difference in both sensitivity and specificity of PCT maps. This was the first study to investigate the accuracy of PCT with the toggling table technique in detection of infratentorial stroke lesions. Clinically, PCT is highly reliable and accurate in detecting infratentorial stroke lesions. (orig.)

Optimising MR perfusion imaging: comparison of different software-based approaches in acute ischaemic stroke

Energy Technology Data Exchange (ETDEWEB)

Schaafs, Lars-Arne [Charite-Universitaetsmedizin, Department of Radiology, Berlin (Germany); Charite-Universitaetsmedizin, Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Berlin (Germany); Porter, David [Fraunhofer Institute for Medical Image Computing MEVIS, Bremen (Germany); Audebert, Heinrich J. [Charite-Universitaetsmedizin, Department of Neurology with Experimental Neurology, Berlin (Germany); Fiebach, Jochen B.; Villringer, Kersten [Charite-Universitaetsmedizin, Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Berlin (Germany)

2016-11-15

Perfusion imaging (PI) is susceptible to confounding factors such as motion artefacts as well as delay and dispersion (D/D). We evaluate the influence of different post-processing algorithms on hypoperfusion assessment in PI analysis software packages to improve the clinical accuracy of stroke PI. Fifty patients with acute ischaemic stroke underwent MRI imaging in the first 24 h after onset. Diverging approaches to motion and D/D correction were applied. The calculated MTT and CBF perfusion maps were assessed by volumetry of lesions and tested for agreement with a standard approach and with the final lesion volume (FLV) on day 6 in patients with persisting vessel occlusion. MTT map lesion volumes were significantly smaller throughout the software packages with correction of motion and D/D when compared to the commonly used approach with no correction (p = 0.001-0.022). Volumes on CBF maps did not differ significantly (p = 0.207-0.925). All packages with advanced post-processing algorithms showed a high level of agreement with FLV (ICC = 0.704-0.879). Correction of D/D had a significant influence on estimated lesion volumes and leads to significantly smaller lesion volumes on MTT maps. This may improve patient selection. (orig.)

Optimising MR perfusion imaging: comparison of different software-based approaches in acute ischaemic stroke

International Nuclear Information System (INIS)

Schaafs, Lars-Arne; Porter, David; Audebert, Heinrich J.; Fiebach, Jochen B.; Villringer, Kersten

2016-01-01

Perfusion imaging (PI) is susceptible to confounding factors such as motion artefacts as well as delay and dispersion (D/D). We evaluate the influence of different post-processing algorithms on hypoperfusion assessment in PI analysis software packages to improve the clinical accuracy of stroke PI. Fifty patients with acute ischaemic stroke underwent MRI imaging in the first 24 h after onset. Diverging approaches to motion and D/D correction were applied. The calculated MTT and CBF perfusion maps were assessed by volumetry of lesions and tested for agreement with a standard approach and with the final lesion volume (FLV) on day 6 in patients with persisting vessel occlusion. MTT map lesion volumes were significantly smaller throughout the software packages with correction of motion and D/D when compared to the commonly used approach with no correction (p = 0.001-0.022). Volumes on CBF maps did not differ significantly (p = 0.207-0.925). All packages with advanced post-processing algorithms showed a high level of agreement with FLV (ICC = 0.704-0.879). Correction of D/D had a significant influence on estimated lesion volumes and leads to significantly smaller lesion volumes on MTT maps. This may improve patient selection. (orig.)

Stringent tests of constrained Minimal Flavor Violation through ΔF=2 transitions

International Nuclear Information System (INIS)

Buras, Andrzej J.; Girrbach, Jennifer

2013-01-01

New Physics contributions to ΔF=2 transitions in the simplest extensions of the Standard Model (SM), the models with constrained Minimal Flavor Violation (CMFV), are parametrized by a single variable S(v), the value of the real box diagram function that in CMFV is bounded from below by its SM value S 0 (x t ). With already very precise experimental values of ε K , ΔM d , ΔM s and precise values of the CP-asymmetry S ψK S and of B K entering the evaluation of ε K , the future of CMFV in the ΔF = 2 sector depends crucially on the values of vertical stroke V cb vertical stroke, vertical stroke V ub vertical stroke, γ, F B s √(B B s ) and F B d √(B B d ). The ratio ξ of the latter two non-perturbative parameters, already rather precisely determined from lattice calculations, allows then together with ΔM s / ΔM d and S ψK S to determine the range of the angle γ in the unitarity triangle independently of the value of S(v). Imposing in addition the constraints from vertical stroke ε K vertical stroke and ΔM d allows to determine the favorite CMFV values of vertical stroke V cb vertical stroke, vertical stroke V ub vertical stroke, F B s √(B B s ) and F B d √(B B d ) as functions of S(v) and γ. The vertical stroke V cb vertical stroke 4 dependence of ε K allows to determine vertical stroke V cb vertical stroke for a given S(v) and γ with a higher precision than it is presently possible using tree-level decays. The same applies to vertical stroke V ub vertical stroke, vertical stroke V td vertical stroke and vertical stroke V ts vertical stroke that are automatically determined as functions of S(v) and γ. We derive correlations between F B s √(B B s ) and F B d √(B B d ), vertical stroke V cb vertical stroke, vertical stroke V ub vertical stroke and γ that should be tested in the coming years. Typically F B s √(B B s ) and F B d √(B B d ) have to be lower than their present lattice values, while vertical stroke V cb vertical stroke has to

Acute stroke unit improves stroke management-four years on from INASC.

Science.gov (United States)

Shanahan, E; Keenan, R; Cunningham, N; O'Malley, G; O'Connor, M; Lyons, D; Peters, C

2015-02-01

The Irish Heart Foundation carried out the Irish National Audit of Stroke Care (INASC) in 2008. Management practices were significantly poorer than those in the UK Sentinel audits. Since then an acute stroke unit has been established in University Hospital Limerick. A stroke database was established. 12 key indicators of stroke management audited by INASC were identified. Results were compared to those in INASC. 89 stroke patients were admitted. 8 of the 12 key indicators scored significantly better than in INASC. 92.5% had a brain scan within 24hrs (INASC-40%, p = strokes received anti-thrombotics (INASC-85%, p = 0.001). 94% had rehab goals agreed by MDT (22% in INASC p = 0.0000). 55% were treated in stroke unit (2% in INASC, p = 0.0000). MDT input improved with regard to physiotherapy (87% vs 43% in INASC, p = Stroke management has significantly improved from 2008, however some deficiencies remain.

Hyperacetylation and differential deacetylation of histones H4 and H3 define two distinct classes of acetylated SV40 chromosomes early in infection

International Nuclear Information System (INIS)

Milavetz, Barry

2004-01-01

SV40 chromosomes undergoing encapsidation late in infection and SV40 chromatin in virions are hyperacetylated on histones H4 and H3. However, the fate of the SV40 chromosomes containing hyperacetylated histones in a subsequent round of infection has not been determined. In order to determine if SV40 chromosomes undergo changes in the extent of histone acetylation during early infection, we have analyzed SV40 chromosomes isolated 30 min and 3 h postinfection by quantitative ChIP assays, depletion ChIP assays, competitive ChIP assays, and ChIP assays combined with restriction endonuclease sensitivity using antibodies to hyperacetylated histones H4 and H3. We have shown that at 30 min postinfection, the hyperacetylated histones are associated with two distinct classes of SV40 chromosomes. One form is hyperacetylated specifically on histone H4 while a second form is hyperacetylated on both H4 and H3. Both forms of chromosomes appear to contain a nucleosome-free promoter region. Over the course of the next few hours of infection, the class of SV40 chromosomes hyperacetylated on only H4 is reduced or completely eliminated through deacetylation

Frequencies of circulating B- and T-lymphocytes as indicators for stroke outcomes

Directory of Open Access Journals (Sweden)

Wang Y

2017-10-01

Full Text Available Yanling Wang,1 Jihong Liu,1 Xuemei Wang,1 Zongjian Liu,2 Fengwu Li,1 Fenghua Chen,3 Xiaokun Geng,1 Zhili Ji,2 Huishan Du,1 Xiaoming Hu1,3 1Department of Neurology, China-America Institute of Neuroscience, 2Central Laboratory, Beijing Luhe Hospital, Capital Medical University, Beijing, People’s Republic of China; 3Department of Neurology, Pittsburgh Institute of Brain Disorders and Recovery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA Background: Stroke has high mortality and morbidity. Biomarkers are required for to predict stroke outcomes, which could help clinicians to provide rationale approaches for patient management. The dynamic changes in circulating immune cells have been reported in stroke patients and animal models of stroke.Aim: The aim of this study was to explore biomarkers to predict stroke outcomes by investigating the relationship between the frequencies of circulating immune cells and stroke outcomes.Methods: In all, 50 acute ischemic stroke (AIS patients were enrolled. Their blood samples were collected upon hospital admission and on day 1 and day 7 after stroke, and the leukocyte subsets were analyzed by flow cytometry. The dynamic changes in some types of immune cells in the AIS course and their correlation with clinical parameters were analyzed. Blood samples from 123 age- and gender-matched healthy subjects were used as controls.Results: The proportions of T-lymphocytes and NK cells in stroke patients were significantly lower than in healthy controls. The frequencies of B- and T-lymphocytes were negatively correlated with stroke severity at onset, including neurological deficits as assessed by National Institutes of Health Stroke Scale (NIHSS, and infarct volume as measured by the diffusion-weighted images (DWIs of magnetic resonance (MR. Logistic regression analysis showed that modified Rankin scale (mRs scores, a score system for the long-term neurological dysfunctions, were negatively correlated

Fast semi-automated lesion demarcation in stroke

Directory of Open Access Journals (Sweden)

Bianca de Haan

2015-01-01

Full Text Available Lesion–behaviour mapping analyses require the demarcation of the brain lesion on each (usually transverse slice of the individual stroke patient's brain image. To date, this is generally thought to be most precise when done manually, which is, however, both time-consuming and potentially observer-dependent. Fully automated lesion demarcation methods have been developed to address these issues, but these are often not practicable in acute stroke research where for each patient only a single image modality is available and the available image modality differs over patients. In the current study, we evaluated a semi-automated lesion demarcation approach, the so-called Clusterize algorithm, in acute stroke patients scanned in a range of common image modalities. Our results suggest that, compared to the standard of manual lesion demarcation, the semi-automated Clusterize algorithm is capable of significantly speeding up lesion demarcation in the most commonly used image modalities, without loss of either lesion demarcation precision or lesion demarcation reproducibility. For the three investigated acute datasets (CT, DWI, T2FLAIR, containing a total of 44 patient images obtained in a regular clinical setting at patient admission, the reduction in processing time was on average 17.8 min per patient and this advantage increased with increasing lesion volume (up to 60 min per patient for the largest lesion volumes in our datasets. Additionally, our results suggest that performance of the Clusterize algorithm in a chronic dataset with 11 T1 images was comparable to its performance in the acute datasets. We thus advocate the use of the Clusterize algorithm, integrated into a simple, freely available SPM toolbox, for the precise, reliable and fast preparation of imaging data for lesion–behaviour mapping analyses.

Measuring of vertical stroke Vub vertical stroke in the forthcoming decade

International Nuclear Information System (INIS)

Kim, C.S.

1997-01-01

I first introduce the importance of measuring V ub precisely. Then, from a theoretician's point of view, I review (a) past history, (b) present trials, and (c) possible future alternatives on measuring vertical stroke V ub vertical stroke and/or vertical stroke V ub /V cb vertical stroke. As of my main topic, I introduce a model-independent method, which predicts Γ(B→X u lν)/Γ(B→X c lν)≡(γ u /γ c ) x vertical stroke V ub /V cb vertical stroke 2 ≅(1.83±0.28) x vertical stroke V ub /V cb vertical stroke 2 and vertical stroke V ub /V cb vertical stroke ≡(γ c /γ u ) 1/2 x [B(B→X u lν)/B(B→ X c lν]) 1/2 ≅(0.74±0.06) x [B(B→X u lν/)B(B→X c lν)] 1/2 , based on the heavy quark effective theory I also explore the possible experimental options to separate B→X u lν from the dominant B→X c lν: the measurement of inclusive hadronic invariant mass distributions, and the 'D-π' (and 'K-π') separation conditions I also clarify the relevant experimental backgrounds. (orig.)

Stroke

Science.gov (United States)

... doctor Preventing falls Stroke - discharge Swallowing problems Images Brain Carotid stenosis, x-ray of the left artery Carotid stenosis, x-ray of the right artery Stroke Brainstem function Cerebellum - function Circle of Willis Left cerebral hemisphere - ...

Stroke prevention in atrial fibrillation: findings from Tuscan FADOI Stroke Registry

Directory of Open Access Journals (Sweden)

Luca Masotti

2014-06-01

Full Text Available Despite vitamin K antagonists (VKAs are considered the first choice treatment for stroke prevention in atrial fibrillation (AF, literature shows their underuse in this context. Since data about VKAs use prior and after acute stroke lack, the aim of this study was to focus on management of anticoagulation with VKAs in this context. Data were retrieved from Tuscan FADOI Stroke Registry, an online data bank aimed to report on characteristics of stroke patients consecutively admitted in Internal Medicine wards in 2010 and 2011. In this period 819 patients with mean age 76.5±12.3 years were enrolled. Data on etiology were available for 715 of them (88.1%, 87% being ischemic and 13% hemorrhagic strokes. AF was present in 238 patients (33%, 165 (69.3% having a known AF before hospitalization, whereas 73 patients (31.7% received a new diagnosis of AF. A percentage of 89% of strokes in patients with known AF were ischemic and 11% hemorrhagic. A percentage of 86.7% of patients with known AF had a CHADS2 ≥2, but only 28.3% were on VKAs before hospitalization. A percentage of 78.8% of patients treated with VKAs before stroke had an international normalized ratio (INR ≤2.0; 68.7% of patients with VKAs-related hemorrhagic strokes had INR ≤3.0. Combined endpoint mortality or severe disability in patients with ischemic stroke associated with AF was present in 47%, while it was present in 19.30% and 19.20% of atherothrombotic and lacunar strokes, respectively. At hospital discharge, VKAs were prescribed in 25.9% of AF related ischemic stroke patients. AF related strokes are burdened by severe outcome but VKAs are dramatically underused in patients with AF, even in higher risk patients. Efforts to improve anticoagulation in this stroke subtype are warranted.

Reduced bone formation markers, and altered trabecular and cortical bone mineral densities of non-paretic femurs observed in rats with ischemic stroke: A randomized controlled pilot study.

Directory of Open Access Journals (Sweden)

Karen N Borschmann

Full Text Available Immobility and neural damage likely contribute to accelerated bone loss after stroke, and subsequent heightened fracture risk in humans.To investigate the skeletal effect of middle cerebral artery occlusion (MCAo stroke in rats and examine its utility as a model of human post-stroke bone loss.Twenty 15-week old spontaneously hypertensive male rats were randomized to MCAo or sham surgery controls. Primary outcome: group differences in trabecular bone volume fraction (BV/TV measured by Micro-CT (10.5 micron istropic voxel size at the ultra-distal femur of stroke affected left legs at day 28. Neurological impairments (stroke behavior and foot-faults and physical activity (cage monitoring were assessed at baseline, and days 1 and 27. Serum bone turnover markers (formation: N-terminal propeptide of type 1 procollagen, PINP; resorption: C-terminal telopeptide of type 1 collagen, CTX were assessed at baseline, and days 7 and 27.No effect of stroke was observed on BV/TV or physical activity, but PINP decreased by -24.5% (IQR -34.1, -10.5, p = 0.046 at day 27. In controls, cortical bone volume (5.2%, IQR 3.2, 6.9 and total volume (6.4%, IQR 1.2, 7.6 were higher in right legs compared to left legs, but these side-to-side differences were not evident in stroke animals.MCAo may negatively affect bone formation. Further investigation of limb use and physical activity patterns after MCAo is required to determine the utility of this current model as a representation of human post-stroke bone loss.

The suitability of 129SvEv mice for studying depressive-like behaviour: both males and females develop learned helplessness.

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Chourbaji, Sabine; Pfeiffer, Natascha; Dormann, Christof; Brandwein, Christiane; Fradley, Rosa; Sheardown, Malcolm; Gass, P

2010-07-29

Behavioural studies using transgenic techniques in mice usually require extensive backcrossing to a defined background strain, e.g. to C57BL/6. In this study we investigated whether backcrossing can be replaced by using the 129SvEv strain from which the embryonic stem cells are generally obtained for gene targeting strategies to analyze e.g. depression-like behaviour. For that purpose we subjected male and female 129SvEv mice to two frequently used depression tests and compared them with commonly used C57BL/6 mice. 129SvEv and C57BL/6 mice exhibited differing profiles with regard to locomotion and pain sensitivity. However, in the learned helplessness paradigm, a procedure, which represents a valid method to detect depressive-like behaviour, 129SvEv animals develop a similar level of helplessness as C57BL/6 mice. One great advantage of the 129SvEv animals though, is the fact that in this strain even females develop helplessness, which could not be produced in C57BL/6 mice. In the tail suspension test, both genders of 129SvEv exhibited more despair behaviour than C57BL/6 animals. We therefore suggest that this strain may be utilized in the establishment of new test procedures for affective diseases, since costly and time-consuming backcrossing can be prevented, depressive-like behaviour may be analyzed effectively, and gender-specific topics could be addressed in an adequate way. Copyright 2010 Elsevier B.V. All rights reserved.

Acute stroke unit improves stroke management-four years on from INASC.

LENUS (Irish Health Repository)

Shanahan, E

2015-02-01

The Irish Heart Foundation carried out the Irish National Audit of Stroke Care (INASC) in 2008. Management practices were significantly poorer than those in the UK Sentinel audits. Since then an acute stroke unit has been established in University Hospital Limerick. A stroke database was established. 12 key indicators of stroke management audited by INASC were identified. Results were compared to those in INASC. 89 stroke patients were admitted. 8 of the 12 key indicators scored significantly better than in INASC. 92.5% had a brain scan within 24hrs (INASC-40%, p = < 0.001). 100% of ischaemic strokes received anti-thrombotics (INASC-85%, p = 0.001). 94% had rehab goals agreed by MDT (22% in INASC p = 0.0000). 55% were treated in stroke unit (2% in INASC, p = 0.0000). MDT input improved with regard to physiotherapy (87% vs 43% in INASC, p = < 0.02) and SALT (74% vs 26%, p = < 0.02). Stroke management has significantly improved from 2008, however some deficiencies remain.

Stroke scale score and early prediction of outcome after stroke

International Nuclear Information System (INIS)

Ahmed, R.; Zuberi, F.Z.; Afsar, S.

2004-01-01

Objective: To evaluate the baseline National Institute of Health Stroke Scale (NIHSS) score as a predictor of functional outcome after ischemic stroke. Subjects and Methods: The study included 50 patients who presented to Civil Hospital, Karachi, during the study period with acute stroke and were evaluated with CT scan of brain. Only those patients were enrolled in the study that had acute ischemic stroke. The enrolled subjects were then evaluated for the neurological impairment using National Institute of Health Stroke Scale (NIHSS). The subjects were followed-up and their functional outcome was assessed using Barthel index (BI) on the 7th day of their admission. Results: Of the fifty patients enrolled in the study, 31 (62%) were males and 19 (38%) were females, with age ranging from 45 years to 95 years and a mean age of 59.9 years. Neurological impairment at presentation was assessed by NIHSS. The score ranged between 2 and 28. The functional outcome was evaluated on the 7th day using Barthel index (BI), which ranged from 0 to 80. NIHSS score was found to be a good predictor of functional outcome in patients with ischemic stroke (p<0.001). Other factors like gender, hypertension and heart disease did not affect the functional recovery in such patients. Various factors were found to be significant for early prediction of stroke recovery. The NIHSS score was the strongest predictor of outcome after ischemic stroke. Age at the time of the event was also found to be an important predictor for stroke recovery. Conclusion: The NIHSS score is a good predictor of patient's recovery after stroke. Assessing the patient's neurological impairment at first presentation of ischemic stroke can guide the physician regarding the prognosis and management plan. (author)

Does use of the recognition of stroke in the emergency room stroke assessment tool enhance stroke recognition by ambulance clinicians?

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Fothergill, Rachael T; Williams, Julia; Edwards, Melanie J; Russell, Ian T; Gompertz, Patrick

2013-11-01

U.K ambulance services assess patients with suspected stroke using the Face Arm Speech Test (FAST). The Recognition Of Stroke In the Emergency Room (ROSIER) tool has been shown superior to the FAST in identifying strokes in emergency departments but has not previously been tested in the ambulance setting. We investigated whether ROSIER use by ambulance clinicians can improve stroke recognition. Ambulance clinicians used the ROSIER in place of the FAST to assess patients with suspected stroke. As the ROSIER includes all FAST elements, we calculated a FAST score from the ROSIER to enable comparisons between the two tools. Ambulance clinicians' provisional stroke diagnoses using the ROSIER and calculated FAST were compared with stroke consultants' diagnosis. We used stepwise logistic regression to compare the contribution of individual ROSIER and FAST items and patient demographics to the prediction of consultants' diagnoses. Sixty-four percent of strokes and 78% of nonstrokes identified by ambulance clinicians using the ROSIER were subsequently confirmed by a stroke consultant. There was no difference in the proportion of strokes correctly detected by the ROSIER or FAST with both displaying excellent levels of sensitivity. The ROSIER detected marginally more nonstroke cases than the FAST, but both demonstrated poor specificity. Facial weakness, arm weakness, seizure activity, age, and sex predicted consultants' diagnosis of stroke. The ROSIER was not better than the FAST for prehospital recognition of stroke. A revised version of the FAST incorporating assessment of seizure activity may improve stroke identification and decision making by ambulance clinicians.

Stimulation of the sphenopalatine ganglion induces reperfusion and blood-brain barrier protection in the photothrombotic stroke model.

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Haviv Levi

Full Text Available The treatment of stroke remains a challenge. Animal studies showing that electrical stimulation of the sphenopalatine ganglion (SPG exerts beneficial effects in the treatment of stroke have led to the initiation of clinical studies. However, the detailed effects of SPG stimulation on the injured brain are not known.The effect of acute SPG stimulation was studied by direct vascular imaging, fluorescent angiography and laser Doppler flowmetry in the sensory motor cortex of the anaesthetized rat. Focal cerebral ischemia was induced by the rose bengal (RB photothrombosis method. In chronic experiments, SPG stimulation, starting 15 min or 24 h after photothrombosis, was given for 3 h per day on four consecutive days. Structural damage was assessed using histological and immunohistochemical methods. Cortical functions were assessed by quantitative analysis of epidural electro-corticographic (ECoG activity continuously recorded in behaving animals.Stimulation induced intensity- and duration-dependent vasodilation and increased cerebral blood flow in both healthy and photothrombotic brains. In SPG-stimulated rats both blood brain-barrier (BBB opening, pathological brain activity and lesion volume were attenuated compared to untreated stroke animals, with no apparent difference in the glial response surrounding the necrotic lesion.SPG-stimulation in rats induces vasodilation of cortical arterioles, partial reperfusion of the ischemic lesion, and normalization of brain functions with reduced BBB dysfunction and stroke volume. These findings support the potential therapeutic effect of SPG stimulation in focal cerebral ischemia even when applied 24 h after stroke onset and thus may extend the therapeutic window of currently administered stroke medications.

Stroke-induced immunodepression and dysphagia independently predict stroke-associated pneumonia - The PREDICT study.

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Hoffmann, Sarah; Harms, Hendrik; Ulm, Lena; Nabavi, Darius G; Mackert, Bruno-Marcel; Schmehl, Ingo; Jungehulsing, Gerhard J; Montaner, Joan; Bustamante, Alejandro; Hermans, Marcella; Hamilton, Frank; Göhler, Jos; Malzahn, Uwe; Malsch, Carolin; Heuschmann, Peter U; Meisel, Christian; Meisel, Andreas

2017-12-01

Stroke-associated pneumonia is a frequent complication after stroke associated with poor outcome. Dysphagia is a known risk factor for stroke-associated pneumonia but accumulating evidence suggests that stroke induces an immunodepressive state increasing susceptibility for stroke-associated pneumonia. We aimed to confirm that stroke-induced immunodepression syndrome is associated with stroke-associated pneumonia independently from dysphagia by investigating the predictive properties of monocytic HLA-DR expression as a marker of immunodepression as well as biomarkers for inflammation (interleukin-6) and infection (lipopolysaccharide-binding protein). This was a prospective, multicenter study with 11 study sites in Germany and Spain, including 486 patients with acute ischemic stroke. Daily screening for stroke-associated pneumonia, dysphagia and biomarkers was performed. Frequency of stroke-associated pneumonia was 5.2%. Dysphagia and decreased monocytic HLA-DR were independent predictors for stroke-associated pneumonia in multivariable regression analysis. Proportion of pneumonia ranged between 0.9% in the higher monocytic HLA-DR quartile (≥21,876 mAb/cell) and 8.5% in the lower quartile (≤12,369 mAb/cell). In the presence of dysphagia, proportion of pneumonia increased to 5.9% and 18.8%, respectively. Patients without dysphagia and normal monocytic HLA-DR expression had no stroke-associated pneumonia risk. We demonstrate that dysphagia and stroke-induced immunodepression syndrome are independent risk factors for stroke-associated pneumonia. Screening for immunodepression and dysphagia might be useful for identifying patients at high risk for stroke-associated pneumonia.

Blood markers of coagulation, fibrinolysis, endothelial dysfunction and inflammation in lacunar stroke versus non-lacunar stroke and non-stroke: systematic review and meta-analysis.

Science.gov (United States)

Wiseman, Stewart; Marlborough, Fergal; Doubal, Fergus; Webb, David J; Wardlaw, Joanna

2014-01-01

The cause of cerebral small vessel disease is not fully understood, yet it is important, accounting for about 25% of all strokes. It also increases the risk of having another stroke and contributes to about 40% of dementias. Various processes have been implicated, including microatheroma, endothelial dysfunction and inflammation. A previous review investigated endothelial dysfunction in lacunar stroke versus mostly non-stroke controls while another looked at markers of inflammation and endothelial damage in ischaemic stroke in general. We have focused on blood markers between clinically evident lacunar stroke and other subtypes of ischaemic stroke, thereby controlling for stroke in general. We systematically assessed the literature for studies comparing blood markers of coagulation, fibrinolysis, endothelial dysfunction and inflammation in lacunar stroke versus non-stroke controls or other ischaemic stroke subtypes. We assessed the quality of included papers and meta-analysed results. We split the analysis on time of blood draw in relation to the stroke. We identified 1,468 full papers of which 42 were eligible for inclusion, including 4,816 ischaemic strokes, of which 2,196 were lacunar and 2,500 non-stroke controls. Most studies subtyped stroke using TOAST. The definition of lacunar stroke varied between studies. Markers of coagulation/fibrinolysis (tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI), fibrinogen, D-dimer) were higher in lacunar stroke versus non-stroke although fibrinogen was no different to non-stroke in the acute phase. tPA and PAI were no different between lacunar and non-lacunar stroke. Fibrinogen and D-dimer were significantly lower in lacunar stroke compared to other ischaemic strokes, both acutely and chronically. Markers of endothelial dysfunction (homocysteine, von Willebrand Factor (vWF), E-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM), vascular cellular adhesion molecule-1 (VCAM)) were higher or

Epilepsy caused by an abnormal alternative splicing with dosage effect of the SV2A gene in a chicken model.

Directory of Open Access Journals (Sweden)

Marine Douaud

Full Text Available Photosensitive reflex epilepsy is caused by the combination of an individual's enhanced sensitivity with relevant light stimuli, such as stroboscopic lights or video games. This is the most common reflex epilepsy in humans; it is characterized by the photoparoxysmal response, which is an abnormal electroencephalographic reaction, and seizures triggered by intermittent light stimulation. Here, by using genetic mapping, sequencing and functional analyses, we report that a mutation in the acceptor site of the second intron of SV2A (the gene encoding synaptic vesicle glycoprotein 2A is causing photosensitive reflex epilepsy in a unique vertebrate model, the Fepi chicken strain, a spontaneous model where the neurological disorder is inherited as an autosomal recessive mutation. This mutation causes an aberrant splicing event and significantly reduces the level of SV2A mRNA in homozygous carriers. Levetiracetam, a second generation antiepileptic drug, is known to bind SV2A, and SV2A knock-out mice develop seizures soon after birth and usually die within three weeks. The Fepi chicken survives to adulthood and responds to levetiracetam, suggesting that the low-level expression of SV2A in these animals is sufficient to allow survival, but does not protect against seizures. Thus, the Fepi chicken model shows that the role of the SV2A pathway in the brain is conserved between birds and mammals, in spite of a large phylogenetic distance. The Fepi model appears particularly useful for further studies of physiopathology of reflex epilepsy, in comparison with induced models of epilepsy in rodents. Consequently, SV2A is a very attractive candidate gene for analysis in the context of both mono- and polygenic generalized epilepsies in humans.

Organizational issues in stroke treatment: The Swiss paradigm - Stroke units

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Georgios K Matis

2013-01-01

Full Text Available Stroke represents the leading cause of acquired disability in adults and poses a tremendous socioeconomic burden both on patients and the society. In this sense, prompt diagnosis and urgent treatment are needed in order to radically reduce the devastating consequences of this disease. Herein the authors present the new guidelines recently adopted by the Swiss Stroke Society concerning the establishment of stroke units. Standardized treatment and allocation protocols along with an acute rehabilitation concept seem to be the core of the Swiss stroke management system. Coordinated multidisciplinary care provided by specialized medical, nursing and therapy staff is of utmost importance for achieving a significant dependency and death reduction. It is believed that the implementation of these guidelines in the stroke care system would be beneficial not only for the stroke patients, but also for the health system.

Alterations of DNA content in human endometrial stromal cells transfected with a temperature-sensitive SV40: tetraploidization and physiological consequences.

Science.gov (United States)

Rinehart, C A; Mayben, J P; Butler, T D; Haskill, J S; Kaufman, D G

1992-01-01

The normal genomic stability of human cells is reversed during neoplastic transformation. The SV40 large T antigen alters the DNA content in human endometrial stromal cells in a manner that relates to neoplastic progression. Human endometrial stromal cells were transfected with a plasmid containing the A209 temperature-sensitive mutant of SV40 (tsSV40), which is also defective in the viral origin of replication. Ninety-seven clonal transfectants from seven different primary cell strains were isolated. Initial analysis revealed that 20% of the clonal populations (19/97) had an apparent diploid DNA content, 35% (34/97) had an apparent tetraploid DNA content, and the remainder were mixed populations of diploid and tetraploid cells. No aneuploid populations were observed. Diploid tsSV40 transformed cells always give rise to a population of cells with a tetraploid DNA content when continuously cultured at the permissive temperature. The doubling of DNA content can be vastly accelerated by the sudden reintroduction of large T antigen activity following a shift from non-permissive to permissive temperature. Tetraploid tsSV40 transfected cells have a lower capacity for anchorage-independent growth and earlier entry into 'crisis' than diploid cells. These results indicate that during the pre-crisis, extended lifespan phase of growth, the SV40 large T antigen causes a doubling of DNA content. This apparent doubling of DNA content does not confer growth advantage during the extended lifespan that precedes 'crisis'.

Prostate and seminal vesicle volume based consideration of prostate cancer patients for treatment with 3D-conformal or intensity-modulated radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Reddy, Nandanuri M. S.; Nori, Dattatreyudu; Chang, Hyesook; Lange, Christopher S.; Ravi, Akkamma [Department of Radiation Oncology, New York Hospital Queens, Flushing, New York 11355 (United States); Department of Radiation Oncology, State University of New York Downstate Medical Center, Brooklyn, New York 11203 (United States); Department of Radiation Oncology, New York Hospital Queens, Flushing, New York 11355 (United States)

2010-07-15

Purpose: The purpose of this article was to determine the suitability of the prostate and seminal vesicle volumes as factors to consider patients for treatment with image-guided 3D-conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT), using common dosimetry parameters as comparison tools. Methods: Dosimetry of 3D and IMRT plans for 48 patients was compared. Volumes of prostate, SV, rectum, and bladder, and prescriptions were the same for both plans. For both 3D and IMRT plans, expansion margins to prostate+SV (CTV) and prostate were 0.5 cm posterior and superior and 1 cm in other dimensions to create PTV and CDPTV, respectively. Six-field 3D plans were prepared retrospectively. For 3D plans, an additional 0.5 cm margin was added to PTV and CDPTV. Prescription for both 3D and IMRT plans was the same: 45 Gy to CTV followed by a 36 Gy boost to prostate. Dosimetry parameters common to 3D and IMRT plans were used for comparison: Mean doses to prostate, CDPTV, SV, rectum, bladder, and femurs; percent volume of rectum and bladder receiving 30 (V30), 50 (V50), and 70 Gy (V70), dose to 30% of rectum and bladder, minimum and maximum point dose to CDPTV, and prescription dose covering 95% of CDPTV (D95). Results: When the data for all patients were combined, mean dose to prostate and CDPTV was higher with 3D than IMRT plans (P<0.01). Mean D95 to CDPTV was the same for 3D and IMRT plans (P>0.2). On average, among all cases, the minimum point dose was less for 3D-CRT plans and the maximum point dose was greater for 3D-CRT than for IMRT (P<0.01). Mean dose to 30% rectum with 3D and IMRT plans was comparable (P>0.1). V30 was less (P<0.01), V50 was the same (P>0.2), and V70 was more (P<0.01) for rectum with 3D than IMRT plans. Mean dose to bladder was less with 3D than IMRT plans (P<0.01). V30 for bladder with 3D plans was less than that of IMRT plans (P<0.01). V50 and V70 for 3D plans were the same for 3D and IMRT plans (P>0.2). Mean dose to femurs

Universal Unitarity Triangle 2016 and the tension between ΔM{sub s,d} and ε{sub K} in CMFV models

Energy Technology Data Exchange (ETDEWEB)

Blanke, Monika [Karlsruhe Institute of Technology, Institut fur Kernphysik, Eggenstein-Leopoldshafen (Germany); Karlsruhe Institute of Technology, Institut fur Theoretische Teilchenphysik, Karlsruhe (Germany); Buras, Andrzej J. [TUM-IAS, Garching (Germany); TUM, Physik Department, Garching (Germany)

2016-04-15

Motivated by the recently improved results from the Fermilab Lattice and MILC Collaborations on the hadronic matrix elements entering ΔM{sub s,d} in B{sup 0}{sub s,d}- anti B{sup 0}{sub s,d} mixing, we determine the universal unitarity triangle (UUT) in models with constrained minimal flavour violation (CMFV). Of particular importance are the very precise determinations of the ratio vertical stroke V{sub ub} vertical stroke / vertical stroke V{sub cb} vertical stroke = 0.0864 ± 0.0025 and of the angle γ = (62.7 ± 2.1) {sup circle}. They follow in this framework from the experimental values of ΔM{sub d}/ΔM{sub s} and of the CP-asymmetry S{sub ψK{sub S}}. As in CMFV models the new contributions to meson mixings can be described by a single flavour-universal variable S(v), we next determine the CKM matrix elements vertical stroke V{sub ts} vertical stroke, vertical stroke V{sub td} vertical stroke, vertical stroke V{sub cb} vertical stroke and vertical stroke V{sub ub} vertical stroke as functions of S(v) using the experimental value of ΔM{sub s} as input. The lower bound on S(v) in these models, derived by us in 2006, implies then upper bounds on these four CKM elements and on the CP-violating parameter ε{sub K}, which turns out to be significantly below its experimental value. This strategy avoids the use of tree-level determinations of vertical stroke V{sub ub} vertical stroke and vertical stroke V{sub cb} vertical stroke, which are presently subject to considerable uncertainties. On the other hand, if ε{sub K} is used instead of ΔM{sub s} as input, ΔM{sub s,d} are found to be significantly above the data. In this manner we point out that the new lattice data have significantly sharpened the tension between ΔM{sub s,d} and ε{sub K} within the CMFV framework. This implies the presence of new physics contributions beyond this framework that are responsible for the breakdown of the flavour universality of the function S(v). We also present the

Electrochemical cleaning of Sv-08G2S wire surface

International Nuclear Information System (INIS)

Kozlov, E.I.; Degtyarev, V.G.; Novikov, M.P.

1981-01-01

Results of industrial tests of the Sv-08G2S wire with different state of surface fwith technological lubrication, after mechanical cleaning, with electrochemically cleaned surface) are presented. Advantages of welding-technological properties of the wire with electroe chemically cleaned surface are shown. An operation principle of the electrochemical cleaning facility is described. A brief specf ification f of the facility is given [ru

A modified Glenn shunt reduces right ventricular stroke work during left ventricular assist device therapy.

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Schiller, Petter; Vikholm, Per; Hellgren, Laila

2016-03-01

Right ventricular (RV) failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) placement and remains hard to predict. We hypothesized that partial surgical exclusion of the RV with a modified Glenn shunt during LVAD treatment would reduce RV stroke work. An LVAD was implanted in eight pigs and a modified Glenn shunt was constructed. A conductance pressure-volume catheter was placed in the right ventricle through the apex. Haemodynamic data and pressure-volume loops were obtained at the following time periods: (i) baseline, (ii) open shunt, (iii) LVAD with closed shunt and (iii) LVAD and open shunt. During LVAD therapy, the right atrial (RA) pressure increased from 9 mmHg (9-9) to 15 mmHg (12-15), P = 0.01. RV stroke volume increased from 30 ml (29-40) to 51 ml (42-53), P work increased to 708 mmHg ml (654-1193) from 535 mmHg ml (424-717), P = 0.04, compared with baseline. During LVAD therapy in combination with a Glenn shunt, the RA pressure decreased from 15 mmHg (12-15) to 10 mmHg (7-11) when compared with LVAD therapy only, P = 0.01. A decrease in RV stroke work from 708 mmHg ml (654-1193) to 465 mmHg ml (366-711), P = 0.04, was seen when the LVAD was combined with a shunt, not significantly different from the baseline value (535 mmHg ml). The developed pressure in the right ventricle decreased from 29 mmHg (26-32) to 21 mmHg (20-24), P work during the use of the shunt with LVAD treatment. A modified Glenn shunt reduced RV volumes, RV stroke work and RA pressure during LVAD therapy in an experimental model of heart failure in pigs. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

A reliability assessment of constrained spherical deconvolution-based diffusion-weighted magnetic resonance imaging in individuals with chronic stroke.

Science.gov (United States)

Snow, Nicholas J; Peters, Sue; Borich, Michael R; Shirzad, Navid; Auriat, Angela M; Hayward, Kathryn S; Boyd, Lara A

2016-01-15

Diffusion-weighted magnetic resonance imaging (DW-MRI) is commonly used to assess white matter properties after stroke. Novel work is utilizing constrained spherical deconvolution (CSD) to estimate complex intra-voxel fiber architecture unaccounted for with tensor-based fiber tractography. However, the reliability of CSD-based tractography has not been established in people with chronic stroke. Establishing the reliability of CSD-based DW-MRI in chronic stroke. High-resolution DW-MRI was performed in ten adults with chronic stroke during two separate sessions. Deterministic region of interest-based fiber tractography using CSD was performed by two raters. Mean fractional anisotropy (FA), apparent diffusion coefficient (ADC), tract number, and tract volume were extracted from reconstructed fiber pathways in the corticospinal tract (CST) and superior longitudinal fasciculus (SLF). Callosal fiber pathways connecting the primary motor cortices were also evaluated. Inter-rater and test-retest reliability were determined by intra-class correlation coefficients (ICCs). ICCs revealed excellent reliability for FA and ADC in ipsilesional (0.86-1.00; preliability for all metrics in callosal fibers (0.85-1.00; preliable approach to evaluate FA and ADC in major white matter pathways, in chronic stroke. Future work should address the reproducibility and utility of CSD-based metrics of tract number and tract volume. Copyright © 2015 Elsevier B.V. All rights reserved.

Lightweight two-stroke cycle aircraft diesel engine technology enablement program, volume 2

Science.gov (United States)

Freen, P. D.; Berenyi, S. G.; Brouwers, A. P.; Moynihan, M. E.

1985-01-01

An experimental Single Cylinder Test Engine Program is conducted to confirm the analytically projected performance of a two-stroke cycle diesel engine for aircraft applications. Testing confirms the ability of a proposed 4-cylinder version of such an engine to reach the target power at altitude in a highly turbocharged configuration. The experimental program defines all necessary parameters to permit a design of a multicylinder engine for eventual flight applications.

Stroke survivors' endorsement of a "stress belief model" of stroke prevention predicts control of risk factors for recurrent stroke.

Science.gov (United States)

Phillips, L Alison; Tuhrim, Stanley; Kronish, Ian M; Horowitz, Carol R

2014-01-01

Perceptions that stress causes and stress-reduction controls hypertension have been associated with poorer blood pressure (BP) control in hypertension populations. The current study investigated these "stress-model perceptions" in stroke survivors regarding prevention of recurrent stroke and the influence of these perceptions on patients' stroke risk factor control. Stroke and transient ischemic attack survivors (N=600) participated in an in-person interview in which they were asked about their beliefs regarding control of future stroke; BP and cholesterol were measured directly after the interview. Counter to expectations, patients who endorsed a "stress-model" but not a "medication-model" of stroke prevention were in better control of their stroke risk factors (BP and cholesterol) than those who endorsed a medication-model but not a stress-model of stroke prevention (OR for poor control=.54, Wald statistic=6.07, p=.01). This result was not explained by between group differences in patients' reported medication adherence. The results have implications for theory and practice, regarding the role of stress belief models and acute cardiac events, compared to chronic hypertension.

Characterization of Chronic Aortic and Mitral Regurgitation Undergoing Valve Surgery Using Cardiovascular Magnetic Resonance.

Science.gov (United States)

Polte, Christian L; Gao, Sinsia A; Johnsson, Åse A; Lagerstrand, Kerstin M; Bech-Hanssen, Odd

2017-06-15

Grading of chronic aortic regurgitation (AR) and mitral regurgitation (MR) by cardiovascular magnetic resonance (CMR) is currently based on thresholds, which are neither modality nor quantification method specific. Accordingly, this study sought to identify CMR-specific and quantification method-specific thresholds for regurgitant volumes (RVols), RVol indexes, and regurgitant fractions (RFs), which denote severe chronic AR or MR with an indication for surgery. The study comprised patients with moderate and severe chronic AR (n = 38) and MR (n = 40). Echocardiography and CMR was performed at baseline and in all operated AR/MR patients (n = 23/25) 10 ± 1 months after surgery. CMR quantification of AR: direct (aortic flow) and indirect method (left ventricular stroke volume [LVSV] - pulmonary stroke volume [PuSV]); MR: 2 indirect methods (LVSV - aortic forward flow [AoFF]; mitral inflow [MiIF] - AoFF). All operated patients had severe regurgitation and benefited from surgery, indicated by a significant postsurgical reduction in end-diastolic volume index and improvement or relief of symptoms. The discriminatory ability between moderate and severe AR was strong for RVol >40 ml, RVol index >20 ml/m 2 , and RF >30% (direct method) and RVol >62 ml, RVol index >31 ml/m 2 , and RF >36% (LVSV-PuSV) with a negative likelihood ratio ≤ 0.2. In MR, the discriminatory ability was very strong for RVol >64 ml, RVol index >32 ml/m 2 , and RF >41% (LVSV-AoFF) and RVol >40 ml, RVol index >20 ml/m 2 , and RF >30% (MiIF-AoFF) with a negative likelihood ratio surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

What about self-management post-stroke? Challenges for stroke survivors, spouses and professionals

NARCIS (Netherlands)

Satink, A.J.H.

2016-01-01

Self-management post-stroke is challenging for many persons after a stroke. In this thesis is explored how stroke survivors, spouses and professionals perceived self-management post-stroke and how the process of self-management post-stroke evolved over time. The following studies are conducted: a

Diabetic Ketoacidosis-Associated Stroke in Children and Youth

Directory of Open Access Journals (Sweden)

Jennifer Ruth Foster

2011-01-01

Full Text Available Diabetic ketoacidosis (DKA is a state of severe insulin deficiency, either absolute or relative, resulting in hyperglycemia and ketonemia. Although possibly underappreciated, up to 10% of cases of intracerebral complications associated with an episode of DKA, and/or its treatment, in children and youth are due to hemorrhage or ischemic brain infarction. Systemic inflammation is present in DKA, with resultant vascular endothelial perturbation that may result in coagulopathy and increased hemorrhagic risk. Thrombotic risk during DKA is elevated by abnormalities in coagulation factors, platelet activation, blood volume and flow, and vascular reactivity. DKA-associated cerebral edema may also predispose to ischemic injury and hemorrhage, though cases of stroke without concomitant cerebral edema have been identified. We review the current literature regarding the pathogenesis of stroke during an episode of DKA in children and youth.

Effect of caffeine on the ultraviolet light induction of SV40 virus from transformed hamster cells

International Nuclear Information System (INIS)

Zamansky, G.B.; Kleinman, L.F.; Little, J.B.; Black, P.H.; Kaplan, J.C.

1976-01-01

The effect of caffeine on the uv light induction of SV40 virus from two transformed hamster cell lines heterogeneous for the induction of infectious virus was studied. The amount of virus induced was significantly increased in both cell lines when exposure to uv light was followed by treatment with caffeine. Caffeine in the absence of uv irradiation did not stimulate virus induction, nor did it stimulate SV40 replication in a lytic infection. There was an apparent difference in the concentrations of caffeine which maximally stimulated SV40 virus induction in the two cell lines. This effect could not be explained by differences in cell survival after exposure to uv light and caffeine. Since caffeine is known to cause the accumulation of gaps formed in DNA during postreplication repair of uv-irradiated rodent cells, our results support the hypothesis that the formation of gaps or breaks in DNA is an important early step in virus induction

Časopis "Módní svět" a "Lada" v kulturním kontextu

OpenAIRE

Šrolová, Kristýna

2010-01-01

The thesis discusses tbe fashion magazine Módní svět (Fashion World) and its enclosure Lada, which it implants into their cultural and historica1 context. The magazine Módní svět (Fashion World) was puhli,hed from 1875 to 1935 and thi, a1,o deline, lhe time circmnscription of tbe themes in tbe thesis. It contextua11y deals with tbe women society during tbe tum of 19th to 20th century, with women's emancipatory movement, with tbe beginning of publishing of rn.agazines for women and fashion mag...

Lightweight two-stroke cycle aircraft diesel engine technology enablement program, volume 1

Science.gov (United States)

Freen, P. D.; Berenyi, S. G.; Brouwers, A. P.; Moynihan, M. E.

1985-01-01

An experimental Single Cylinder Test Engine Program is conducted to confirm the analytically projected performance of a two-stroke cycle diesel engine for aircraft applications. The test engine delivered 78kW indicated power from 1007cc displacement, operating at 3500 RPM on Schnuerle loop scavenged two-stroke cycle. Testing confirms the ability of a proposed 4-cylinder version of such an engine to reach the target power at altitude, in a highly turbocharged configuration. The experimental program defines all necessary parameters to permit design of a multicylinder engine for eventual flight applications; including injection system requirement, turbocharging, heat rejection, breathing, scavenging, and structural requirements. The multicylinder engine concept is configured to operate with an augmented turbocharger, but with no primary scavenge blower. The test program is oriented to provide a balanced turbocharger compressor to turbine power balance without an auxiliary scavenging system. Engine cylinder heat rejection to the ambient air has been significantly reduced and the minimum overall turbocharger efficiency required is within the range of commercially available turbochargers. Analytical studies and finite element modeling is made of insulated configurations of the engines - including both ceramic and metallic versions. A second generation test engine is designed based on current test results.

Tissue Is More Important than Time in Stroke Patients Being Assessed for Thrombolysis.

Science.gov (United States)

Bivard, Andrew; Spratt, Neil; Miteff, Ferdinand; Levi, Christopher; Parsons, Mark William

2018-01-01

The relative prognostic importance of modern imaging profiles compared with standard clinical characteristics is uncertain in acute stroke patients. In this study, we aimed to compare baseline multimodal CT imaging measures with known clinical predictors of patient outcome at 3 months [modified Rankin scale (mRS)]. We collected baseline, 24 h, and day 90 clinical and imaging data from acute ischemic stroke patients being assessed for thrombolytic therapy between 2010 and 2015 at a single center as part of a retrospective analysis. 561 patients presenting within 4.5 h of ischemic stroke onset who were eligible for thrombolysis based on standard clinical criteria were assessed. Acute infarct core volume on CTP was the strongest univariate predictor of patient outcome (mRS 0-2, R 2 0.497, p  Time to treatment (mRS 0-2, R 2 0.096, p  = 0.01) and age (mRS 0-2, R 2 0.027, p  = 0.013) were relatively weak univariate baseline clinical predictors of 3-month outcome. In multivariate analysis, acute infarct core volume and collateral grade were the only significant baseline predictors of 3-month disability (both p  time to treatment and NIHSS, were not as strongly predictive as multimodal CT variables.

European Registry of Carotid Artery Stenting: results from a prospective registry of eight high volume EUROPEAN institutions.

Science.gov (United States)

Stabile, Eugenio; Garg, Pallav; Cremonesi, Alberto; Bosiers, Marc; Reimers, Bernhard; Setacci, Carlo; Cao, Piergiorgio; Schmidt, Andrej; Sievert, Horst; Peeters, Patrick; Nikas, Dimitry; Werner, Martin; de Donato, Gianmarco; Parlani, Giambattista; Castriota, Fausto; Hornung, Marius; Mauri, Laura; Rubino, Paolo

2012-08-01

Carotid endarterectomy (CEA) is the standard revascularization therapy to prevent stroke in patients with carotid artery disease. Carotid artery stenting (CAS) could be considered a potential alternative in patients at high surgical risk. Recent clinical trials have challenged this concept due a relatively high incidence of post-CAS adverse events, which occurred in low volume centers. The aim of this study was to evaluate the outcomes associated with neuroprotected CAS in selected high volume centers. From January 2007 to December 2007, 1,611 patients underwent neuroprotected CAS in eight European Centers. For each patients, clinical, procedural, and one month follow-up data from all patients have been collected. An independent clinical events committee adjudicated the events. Overall in hospital death was 0.06% (one patient), whereas in-hospital stroke was 0.49% (eight patients). Between hospital discharge and 30 days three additional patients died (0.18%) and 10 patients experienced a stroke (0.67%). Overall 30 days mortality was 0.24% (four patients) and stroke incidence 1.12% (18 patients). The 30 day stroke/death rate was 1.36%. CAS is a reasonable alternative to CEA to treat carotid artery atherosclerosis in well-experienced high volume centers. These data suggest that future prospective trials comparing CAS and CEA outcomes should include only centers highly experienced in both treatment modalities. Copyright © 2012 Wiley Periodicals, Inc.

A high-quality narrow passband filter for elastic SV waves via aligned parallel separated thin polymethylmethacrylate plates

OpenAIRE

Jun Zhang; Yaolu Liu; Wensheng Yan; Ning Hu

2017-01-01

We designed a high-quality filter that consists of aligned parallel polymethylmethacrylate (PMMA) thin plates with small gaps for elastic SV waves propagate in metals. Both the theoretical model and the full numerical simulation show the transmission spectrum of the elastic SV waves through such a filter has several sharp peaks with flawless transmission within the investigated frequencies. These peaks can be readily tuned by manipulating the geometry parameters of the PMMA plates. Our invest...

Transformation and radiosensitivity of human diploid skin fibroblasts transfected with SV40 T-antigen mutants defective in RB and P53 binding domains

International Nuclear Information System (INIS)

LingNah Su; Little, J.B.

1992-01-01

A series of human diploid fibroblast cell clones were developed by DNA transfection with either wild-type SV40 T-antigen (SV40T) or T-antigen mutants defective in its various functional domains. Cell clones expressing the wild-type SV40 T were significantly radioresistant as compared with clones transfected with the neo gene only (D o 192 ± 13 vs 127 ± 19). This radioresistance persisted in post-crisis, immortalized cell lines. A series of mutants with point or deletion mutations within each functionally active domain of SV40 T were also examined for their ability to alter radiosensitivity and induce morphological transformation. Cell clones transfected with T-antigen mutants defective in nuclear localization or origin binding showed increased radioresistance similar to clones transfected with wild-type T-antigen, and expressed morphological changes characteristic of SV40 T-transfected cells. (author)

The effects of postural changes of baroreflex gain in normal and hypertensive pregnancies.

Science.gov (United States)

Miyake, Yoshiaki; Ohnishi, Miyako; Fujii, T K; Yamamoto, Tatsuo; Yoneda, Chika; Takahashi, Sachie; Ichimaru, Yuhei

2002-01-01

In order to understand the changes of baroreflex gain due to postural changes in normal pregnancies, we measured percentage changes (% changes) in blood pressure (SBP, DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) as well as cardiac autonomic nervous function (HF as an index of parasympathetic and LF/HF as an index of sympathetic function) and compared these parameters in normal pregnancies with those found in hypertensive pregnancies, such as chronic hypertensive (CHP) and severe preeclamptic pregnancies (PE), in late pregnancy (after 32 wks). When the position was changed from supine to standing in normal and non-pregnant women, the % changes of HR, DBP, TPR and LF/HF were increased and SBP, SV, CO and HF were decreased. The % changes of these parameters, however, were gradually decreased as pregnancy progressed, especially after 20-24 wks of gestation. In hypertensive pregnancies, however, even in late pregnancy, the decreased SBP and increased TPR was still observed and the profound decrease of CO and SV and increase of TPR were characteristic in PE when compared to CHP.

The IMPACT shirt: textile integrated and portable impedance cardiography

International Nuclear Information System (INIS)

Ulbrich, Mark; Wan, Tingting; Leonhardt, Steffen; Walter, Marian; Mühlsteff, Jens; Sipilä, Auli; Kamppi, Merja; Koskela, Anne; Myry, Manu

2014-01-01

Measurement of hemodynamic parameters such as stroke volume (SV) via impedance cardiography (ICG) is an easy, non-invasive and inexpensive way to assess the health status of the heart. We present a possibility to use this technology for monitoring risk patients at home. The IMPACT Shirt (IMPedAnce Cardiography Textile) has been developed with integrated textile electrodes and textile wiring, as well as with portable miniaturized hardware. Several textile materials were characterized in vitro and in vivo to analyze their performance with regard to washability, and electrical characteristics such as skin-electrode impedance, capacitive coupling and subjective tactile feeling. The small lightweight hardware measures ECG and ICG continuously and transmits wireless data via Bluetooth to a mobile phone (Android) or PC for further analysis. A lithium polymer battery supplies the circuit and can be charged via a micro-USB. Results of a proof-of-concept trial show excellent agreement between SV assessed by a commercial device and the developed system. The IMPACT Shirt allows monitoring of SV and ECG on a daily basis at the patient’s home. (paper)

Stringent tests of constrained Minimal Flavor Violation through {Delta}F=2 transitions

Energy Technology Data Exchange (ETDEWEB)

Buras, Andrzej J. [TUM-IAS, Garching (Germany); Girrbach, Jennifer [TUM, Physik Department, Garching (Germany)

2013-09-15

New Physics contributions to {Delta}F=2 transitions in the simplest extensions of the Standard Model (SM), the models with constrained Minimal Flavor Violation (CMFV), are parametrized by a single variable S(v), the value of the real box diagram function that in CMFV is bounded from below by its SM value S{sub 0}(x{sub t}). With already very precise experimental values of {epsilon}{sub K}, {Delta}M{sub d}, {Delta}M{sub s} and precise values of the CP-asymmetry S{sub {psi}K{sub S}} and of B{sub K} entering the evaluation of {epsilon}{sub K}, the future of CMFV in the {Delta}F = 2 sector depends crucially on the values of vertical stroke V{sub cb} vertical stroke, vertical stroke V{sub ub} vertical stroke, {gamma}, F{sub B{sub s}} {radical}(B{sub B{sub s}}) and F{sub B{sub d}} {radical}(B{sub B{sub d}}). The ratio {xi} of the latter two non-perturbative parameters, already rather precisely determined from lattice calculations, allows then together with {Delta}M{sub s} / {Delta}M{sub d} and S{sub {psi}K{sub S}} to determine the range of the angle {gamma} in the unitarity triangle independently of the value of S(v). Imposing in addition the constraints from vertical stroke {epsilon}{sub K} vertical stroke and {Delta}M{sub d} allows to determine the favorite CMFV values of vertical stroke V{sub cb} vertical stroke, vertical stroke V{sub ub} vertical stroke, F{sub B{sub s}} {radical}(B{sub B{sub s}}) and F{sub B{sub d}} {radical}(B{sub B{sub d}}) as functions of S(v) and {gamma}. The vertical stroke V{sub cb} vertical stroke {sup 4} dependence of {epsilon}{sub K} allows to determine vertical stroke V{sub cb} vertical stroke for a given S(v) and {gamma} with a higher precision than it is presently possible using tree-level decays. The same applies to vertical stroke V{sub ub} vertical stroke, vertical stroke V{sub td} vertical stroke and vertical stroke V{sub ts} vertical stroke that are automatically determined as functions of S(v) and {gamma}. We derive correlations

Measurement of vertical stroke Vub vertical stroke using b hadron semileptonic decay

International Nuclear Information System (INIS)

Abbiendi, G.; Aakesson, P.F.

2001-01-01

The magnitude of the CKM matrix element vertical stroke V ub vertical stroke is determined by measuring the inclusive charmless semileptonic branching fraction of beauty hadrons at OPAL based on b → X u lν event topology and kinematics. This analysis uses OPAL data collected between 1991 and 1995, which correspond to about four million hadronic Z decays. We measure Br(b → X u lν) to be (1.63 ±0.53 +0.55 -0.62 ) x 10 -3 . The first uncertainty is the statistical error and the second is the systematic error. From this analysis, vertical stroke V ub vertical stroke is determined to be: vertical stroke V ub vertical stroke =(4.00±0.65(stat) +0.67 -0.76 (sys)±0.19(HQE)) x 10 -3 . The last error represents the theoretical uncertainties related to the extraction of vertical stroke V ub vertical stroke from Br(b→X u l ν) using the Heavy Quark Expansion. (orig.)

Seizure development after stroke.

Science.gov (United States)

Misirli, H; Ozge, A; Somay, G; Erdoğan, N; Erkal, H; Erenoğlu, N Y

2006-12-01

Although there have been many studies on seizures following stroke, there is still much we do not know about them. In this study, we evaluated the characteristics of seizures in stroke patients. There were 2267 patients with a first-ever stroke, and after excluding 387 patients, 1880 were available for analysis. Of these 1880 patients, we evaluated 200 patients with seizures and 400 patients without seizures. We investigated the seizures according to age, gender, stroke type, the aetiology of ischaemic stroke and the localisation of the lesion. The seizures were classified as early onset and late onset and the seizure type as partial, generalised or secondarily generalised. Seizures occurred in 200 (10.6%) of 1880 strokes. The number of patients with seizures were 138 (10.6%) in ischaemic stroke group and 62 (10.7%) in haemorrhagic stroke group. Patients with ischaemic strokes had 41 embolic (29.7%) and 97 thrombotic (70.3%) origin, and these were not statistically significant in comparison with controls. Cortical involvement for the development of seizures was the most important risk factor (odds ratios = 4.25, p < 0.01). It was concluded that embolic strokes, being younger than 65 years old, and cortical localisation of stroke were important risks for developing seizures.

Clinical Epidemiology Of Stroke

Directory of Open Access Journals (Sweden)

Nagaraja D

2005-01-01

Full Text Available Stroke is a huge public health problem because of its high morbidity and disability. The epidemiology of stroke is of relevance to construct practical paradigms to tackle this major health issue in the community. Recent data have shown that about 72-86% of strokes are ischemic, 9-18% are due to hemorrhage (intracerebral of subarachnoid and the rest are undefined. The risk factors for stroke are multiple and combined. At present, stroke is no more considered as unavoidable and untreatable. It is an emergency and specialized units and teams improve outcome and lower costs. Death related to stroke is declining in many countries and in both sexes. This decrease in multifactorial. The detection and more effective treatment of hypertension may play an important factor, as well as the improved medical care and improvement in diagnostic procedures. While stroke incidence appears stable and stroke mortality is slowly declining, the absolute magnitude of stroke is likely to grow over the next 30 years. as the population ages, the absolute number of stroke victims and demands on healthcare and other support systems is likely to increase substantially in the future. Keeping this in perspective, this chapter shall focus on the epidemiology of stroke in the world and in Indian, in particular.

Stroke in Commercial Flights.

Science.gov (United States)

Álvarez-Velasco, Rodrigo; Masjuan, Jaime; DeFelipe, Alicia; Corral, Iñigo; Estévez-Fraga, Carlos; Crespo, Leticia; Alonso-Cánovas, Araceli

2016-04-01

Stroke on board aircraft has been reported in retrospective case series, mainly focusing on economy class stroke syndrome. Data on the actual incidence, pathogenesis, and prognosis of stroke in commercial flights are lacking. A prospective registry was designed to include all consecutive patients referred from an international airport (40 million passengers a year) to our hospital with a diagnosis of ischemic stroke or transient ischemic attack and onset of symptoms during a flight or immediately after landing. Forty-four patients (32 ischemic strokes and 12 transient ischemic attacks) were included over a 76-month period (January 2008 to April 2014). The estimated incidence of stroke was 1 stroke in 35 000 flights. Pathogeneses of stroke or transient ischemic attack were atherothrombotic in 16 (36%), economy class stroke syndrome in 8 (18%), cardioembolic in 7 (16%), arterial dissection in 4 (9%), lacunar stroke in 4 (9%), and undetermined in 5 (12%) patients. Carotid stenosis >70% was found in 12 (27%) of the patients. Overall prognosis was good, and thrombolysis was applied in 44% of the cases. The most common reason for not treating patients who had experienced stroke onset midflight was the delay in reaching the hospital. Only 1 patient with symptom onset during the flight prompted a flight diversion. We found a low incidence of stroke in the setting of air travel. Economy class stroke syndrome and arterial dissection were well represented in our sample. However, the main pathogenesis was atherothrombosis with a high proportion of patients with high carotid stenosis. © 2016 American Heart Association, Inc.

Genome-wide meta-analysis of cerebral white matter hyperintensities in patients with stroke

NARCIS (Netherlands)

Traylor, M.; Zhang, C.R.; Adib-Samii, P.; Devan, W.J.; Parsons, O.E.; Lanfranconi, S.; Gregory, S.; Cloonan, L.; Falcone, G.J.; Radmanesh, F.; Fitzpatrick, K.; Kanakis, A.; Barrick, T.R.; Moynihan, B.; Lewis, C.M.; Boncoraglio, G.B.; Lemmens, R.; Thijs, V.; Sudlow, C.; Wardlaw, J.; Rothwell, P.M.; Meschia, J.F.; Worrall, B.B.; Levi, C.; Bevan, S.; Furie, K.L.; Dichgans, M.; Rosand, J.; Markus, H.S.; Rost, N.; Klijn, C.J.M.; et al.,

2016-01-01

OBJECTIVE: For 3,670 stroke patients from the United Kingdom, United States, Australia, Belgium, and Italy, we performed a genome-wide meta-analysis of white matter hyperintensity volumes (WMHV) on data imputed to the 1000 Genomes reference dataset to provide insights into disease mechanisms.

Glibenclamide for the treatment of ischemic and hemorrhagic stroke.

Science.gov (United States)

Caffes, Nicholas; Kurland, David B; Gerzanich, Volodymyr; Simard, J Marc

2015-03-04

Ischemic and hemorrhagic strokes are associated with severe functional disability and high mortality. Except for recombinant tissue plasminogen activator, therapies targeting the underlying pathophysiology of central nervous system (CNS) ischemia and hemorrhage are strikingly lacking. Sur1-regulated channels play essential roles in necrotic cell death and cerebral edema following ischemic insults, and in neuroinflammation after hemorrhagic injuries. Inhibiting endothelial, neuronal, astrocytic and oligodendroglial sulfonylurea receptor 1-transient receptor potential melastatin 4 (Sur1-Trpm4) channels and, in some cases, microglial KATP (Sur1-Kir6.2) channels, with glibenclamide is protective in a variety of contexts. Robust preclinical studies have shown that glibenclamide and other sulfonylurea agents reduce infarct volumes, edema and hemorrhagic conversion, and improve outcomes in rodent models of ischemic stroke. Retrospective studies suggest that diabetic patients on sulfonylurea drugs at stroke presentation fare better if they continue on drug. Additional laboratory investigations have implicated Sur1 in the pathophysiology of hemorrhagic CNS insults. In clinically relevant models of subarachnoid hemorrhage, glibenclamide reduces adverse neuroinflammatory and behavioral outcomes. Here, we provide an overview of the preclinical studies of glibenclamide therapy for CNS ischemia and hemorrhage, discuss the available data from clinical investigations, and conclude with promising preclinical results that suggest glibenclamide may be an effective therapeutic option for ischemic and hemorrhagic stroke.

Glibenclamide for the Treatment of Ischemic and Hemorrhagic Stroke

Directory of Open Access Journals (Sweden)

Nicholas Caffes

2015-03-01

Full Text Available Ischemic and hemorrhagic strokes are associated with severe functional disability and high mortality. Except for recombinant tissue plasminogen activator, therapies targeting the underlying pathophysiology of central nervous system (CNS ischemia and hemorrhage are strikingly lacking. Sur1-regulated channels play essential roles in necrotic cell death and cerebral edema following ischemic insults, and in neuroinflammation after hemorrhagic injuries. Inhibiting endothelial, neuronal, astrocytic and oligodendroglial sulfonylurea receptor 1–transient receptor potential melastatin 4 (Sur1–Trpm4 channels and, in some cases, microglial KATP (Sur1–Kir6.2 channels, with glibenclamide is protective in a variety of contexts. Robust preclinical studies have shown that glibenclamide and other sulfonylurea agents reduce infarct volumes, edema and hemorrhagic conversion, and improve outcomes in rodent models of ischemic stroke. Retrospective studies suggest that diabetic patients on sulfonylurea drugs at stroke presentation fare better if they continue on drug. Additional laboratory investigations have implicated Sur1 in the pathophysiology of hemorrhagic CNS insults. In clinically relevant models of subarachnoid hemorrhage, glibenclamide reduces adverse neuroinflammatory and behavioral outcomes. Here, we provide an overview of the preclinical studies of glibenclamide therapy for CNS ischemia and hemorrhage, discuss the available data from clinical investigations, and conclude with promising preclinical results that suggest glibenclamide may be an effective therapeutic option for ischemic and hemorrhagic stroke.

Diffusion imaging and transcranial magnetic stimulation assessment of transcallosal pathways in chronic stroke.

Science.gov (United States)

Mang, Cameron S; Borich, Michael R; Brodie, Sonia M; Brown, Katlyn E; Snow, Nicholas J; Wadden, Katie P; Boyd, Lara A

2015-10-01

To examine the relationship of transcallosal pathway microstructure and transcallosal inhibition (TCI) with motor function and impairment in chronic stroke. Diffusion-weighted magnetic resonance imaging and transcranial magnetic stimulation (TMS) data were collected from 24 participants with chronic stroke and 11 healthy older individuals. Post-stroke motor function (Wolf Motor Function Test) and level of motor impairment (Fugl-Meyer score) were evaluated. Fractional anisotropy (FA) of transcallosal tracts between prefrontal cortices and the mean amplitude decrease in muscle activity during the ipsilateral silent period evoked by TMS over the non-lesioned hemisphere (termed NL-iSPmean) were significantly associated with level of motor impairment and motor function after stroke (p<0.05). A regression model including age, post-stroke duration, lesion volume, lesioned corticospinal tract FA, transcallosal prefrontal tract FA and NL-iSPmean accounted for 84% of variance in motor impairment (p<0.01). Both transcallosal prefrontal tract FA (ΔR(2)=0.12, p=0.04) and NL-iSPmean (ΔR(2)=0.09, p=0.04) accounted for unique variance in motor impairment level. Prefrontal transcallosal tract microstructure and TCI are each uniquely associated with motor impairment in chronic stroke. Utilizing a multi-modal approach to assess transcallosal pathways may improve our capacity to identify important neural substrates of motor impairment in the chronic phase of stroke. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Stroke care: Experiences and clinical research in stroke units in Chennai

Directory of Open Access Journals (Sweden)

Gobindram Arjundas

2006-01-01

Full Text Available Background: S troke is the second commonest cause of death in India with crude overall prevalence rate of 220 per 100,000. With an increasing aging population at risk, the stroke burden in India can be expected to reach epidemic proportions. Materials and Methods: The first protocol-based prospective studies, funded by private agencies was conducted in Madras Institute of Neurology in 1984-86. The results led to establishment of the first stroke unit in Tamil Nadu state, in the institute. The first all-India hospital-based studies in acute stroke was completed as INDIAN COOPERATIVE ACUTE STROKE STUDIES (ICASS I and ICASS II with WHO STEP ONE by members of the Indian Stroke Association between 2000-2005. This has generated very useful data for our country. Results: Mortality in 1984-86 was 40%. Stroke unit in the institute dropped it to 12%. About 10 years later, ICASS studies showed a further fall of mortality to 8%, which is the current international figure in the west. Morbidity pattern showed about half return to their original activities. But about one third are left totally disabled needing prolonged care, for which fiscal, social and rehab provisions have to be done on a national basis. Conclusions: The progress and success of care of Stroke in the last three decades, from treatment in medical and neurology wards to specialized stroke units is presented. The main risk factors are hypertension, diabetes and ischemic heart disease across the country. Hypertension alone or with the other two diseases was present in 72% of cases. Prevention and treatment of these factors will reduce the stroke burden, mortality and morbidity of strokes. The Stroke-team concept can be extended to the smallest hospitals in our country.

Effect of thermal stress on Frank-Starling relations in humans

DEFF Research Database (Denmark)

Wilson, T.E.; Brothers, R.M.; Tollund, C.

2009-01-01

The Frank-Starling 'law of the heart' is implicated in certain types of orthostatic intolerance in humans. Environmental conditions have the capacity to modulate orthostatic tolerance, where heat stress decreases and cooling increases orthostatic tolerance. The objective of this project was to test...... the hypothesis that heat stress augments and cooling attenuates orthostatic-induced decreases in stroke volume (SV) via altering the operating position on a Frank-Starling curve. Pulmonary artery catheters were placed in 11 subjects for measures of pulmonary capillary wedge pressure (PCWP) and SV (thermodilution...... derived cardiac output/heart rate). Subjects experienced lower-body negative-pressure (LBNP) of 0, 15 and 30 mmHg during normothermia, skin-surface cooling (decrease in mean skin temperature of 4.3 +/- 0.4 degrees C (mean +/- s.e.m.) via perfusing 16 degrees C water through a tubed-lined suit), and whole...

Crystal Structure of Botulinum Neurotoxin A2 in Complex with the Human Protein Receptor SV2C Reveals Plasticity in Receptor Binding

Directory of Open Access Journals (Sweden)

Robert Gustafsson

2018-04-01

Full Text Available Botulinum neurotoxins (BoNTs are a family of highly dangerous bacterial toxins, with seven major serotypes (BoNT/A-G. Members of BoNTs, BoNT/A1 and BoNT/B1, have been utilized to treat an increasing number of medical conditions. The clinical trials are ongoing for BoNT/A2, another subtype of BoNT/A, which showed promising therapeutic properties. Both BoNT/A1 and BoNT/A2 utilize three isoforms of synaptic vesicle protein SV2 (SV2A, B, and C as their protein receptors. We here present a high resolution (2.0 Å co-crystal structure of the BoNT/A2 receptor-binding domain in complex with the human SV2C luminal domain. The structure is similar to previously reported BoNT/A-SV2C complexes, but a shift of the receptor-binding segment in BoNT/A2 rotates SV2C in two dimensions giving insight into the dynamic behavior of the interaction. Small differences in key residues at the binding interface may influence the binding to different SV2 isoforms, which may contribute to the differences between BoNT/A1 and BoNT/A2 observed in the clinic.

Analysis of speed, stroke rate, and stroke distance for world-class breaststroke swimming.

Science.gov (United States)

Garland Fritzdorf, Stephen; Hibbs, Angela; Kleshnev, Valery

2009-02-15

Speed in aquatic locomotion is determined by stroke distance and stroke rate, but it does not always follow that an increase in stroke rate will lead to an increase in speed. Kleshnev (2006) developed a method to evaluate the relationship between speed and stroke rate during rowing - the effective work per stroke. In this case study, the effective work per stroke was determined for a male world-class 100-m breaststroke swimmer for seven races in major championships and compared between: each of the seven races; each quarter within each race; and the best swims of this case study and seven other world-class swimmers. The effective work per stroke was related to race performance, with the fastest race having the highest effective work per stroke and lowest stroke rate, with slower races having low effectiveness and high stroke rate (R(2) = 0.85). The effective work per stroke was reduced in a race as the swimmer fatigued. The within-race standard deviation of effectiveness was lower in fast swims (R(2) = 0.84). This analysis has identified some characteristics of fast swimming: high effectiveness, optimal stroke rate, and a flat effectiveness profile. Training and racing strategies can now be devised to improve performance by increasing the sensitivity of assessment of strengths and weaknesses in individuals.

Stroke Burden in Rwanda: A Multicenter Study of Stroke Management and Outcome.

Science.gov (United States)

Nkusi, Agabe Emmy; Muneza, Severien; Nshuti, Steven; Hakizimana, David; Munyemana, Paulin; Nkeshimana, Menelas; Rudakemwa, Emmanuel; Amendezo, Etienne

2017-10-01

Cerebrovascular accidents or stroke constitute the second leading cause of mortality worldwide. Low- and middle-income countries bear most of the stroke burden worldwide. The main objective of this study is to determine the burden of stroke in Rwanda. This was a prospective observational study in 2 parts: 6 months baseline data collection and outcome assessment sessions at 1 year. A total of 96 patients were enrolled in our series. Stroke constituted 2100 per 100,000 population. Of all patients, 55.2% were male and most (60%) were 55 years and older. Of all patients and/or caretakers, 22% were not aware of their previous health status and 53.5% of hypertensive patients were not on treatment by the time of the event. Median presentation delay was 72 hours for patients with ischemic stroke and 24 hours for patients with hemorrhagic stroke. Most patients had hemorrhagic stroke (65% vs. 35%), and more patients with hemorrhagic stroke presented with loss of consciousness (80% vs. 51%). Many patients (62% ischemic group and 44% hemorrhagic group) presented with severe stroke scores, and this was associated with worst outcome (P = 0.004). At 1 year follow-up, 24.7% had no or mild disability, 14.3% were significantly disabled, and 61% had died. Our results show that stroke is a significant public health concern in Rwanda. Risk factor awareness and control are still low and case fatality of stroke is significantly high. The significant delay in presentation to care and presentation with severe stroke are major contributors for the high mortality and severe disability rates. Copyright © 2017 Elsevier Inc. All rights reserved.

The Riks-Stroke story: building a sustainable national register for quality assessment of stroke care.

Science.gov (United States)

Asplund, Kjell; Hulter Åsberg, Kerstin; Appelros, Peter; Bjarne, Daniela; Eriksson, Marie; Johansson, Asa; Jonsson, Fredrik; Norrving, Bo; Stegmayr, Birgitta; Terént, Andreas; Wallin, Sari; Wester, Per-Olov

2011-04-01

Riks-Stroke, the Swedish Stroke Register, is the world's longest-running national stroke quality register (established in 1994) and includes all 76 hospitals in Sweden admitting acute stroke patients. The development and maintenance of this sustainable national register is described. Riks-Stroke includes information on the quality of care during the acute phase, rehabilitation and secondary prevention of stroke, as well as data on community support. Riks-Stroke is unique among stroke quality registers in that patients are followed during the first year after stroke. The data collected describe processes, and medical and patient-reported outcome measurements. The register embraces most of the dimensions of health-care quality (evidence-based, safe, provided in time, distributed fairly and patient oriented). Annually, approximately 25,000 patients are included. In 2009, approximately 320,000 patients had been accumulated (mean age 76-years). The register is estimated to cover 82% of all stroke patients treated in Swedish hospitals. Among critical issues when building a national stroke quality register, the delicate balance between simplicity and comprehensiveness is emphasised. Future developments include direct transfer of data from digital medical records to Riks-Stroke and comprehensive strategies to use the information collected to rapidly implement new evidence-based techniques and to eliminate outdated methods in stroke care. It is possible to establish a sustainable quality register for stroke at the national level covering all hospitals admitting acute stroke patients. Riks-Stroke is fulfilling its main goals to support continuous quality improvement of Swedish stroke services and serve as an instrument for following up national stroke guidelines. © 2010 The Authors. International Journal of Stroke © 2010 World Stroke Organization.

Perfusion CT in acute stroke

International Nuclear Information System (INIS)

Eckert, Bernd; Roether, Joachim; Fiehler, Jens; Thomalla, Goetz

2015-01-01

Modern multislice CT scanners enable multimodal protocols including non-enhanced CT, CT angiography, and CT perfusion. A 64-slice CT scanner provides 4-cm coverage. To cover the whole brain, a 128 - 256-slice scanner is needed. The use of perfusion CT requires an optimized scan protocol in order to reduce exposure to radiation. As compared to non-enhanced CT and CT angiography, the use of CT perfusion increases detection rates of cerebral ischemia, especially small cortical ischemic lesions, while the detection of lacunar and infratentorial stroke lesions remains limited. Perfusion CT enables estimation of collateral flow in acute occlusion of large intra- or extracranial arteries. Currently, no established reliable thresholds are available for determining infarct core and penumbral tissue by CT perfusion. Moreover, perfusion parameters depend on the processing algorithms and the software used for calculation. However, a number of studies point towards a reduction of cerebral blood volume (CBV) below 2 ml/100 g as a critical threshold that identifies infarct core. Large CBV lesions are associated with poor outcome even in the context of recanalization. The extent of early ischemic signs on non-enhanced CT remains the main parameter from CT imaging to guide acute reperfusion treatment. Nevertheless, perfusion CT increases diagnostic and therapeutic certainty in the acute setting. Similar to stroke MRI, perfusion CT enables the identification of tissue at risk of infarction by the mismatch between infarct core and the larger area of critical hypoperfusion. Further insights into the validity of perfusion parameters are expected from ongoing trials of mechanical thrombectomy in stroke.

[Assessment of the right ventricular function in healthy volunteers with one beat full-volume real-time three-dimensional echocardiography].

Science.gov (United States)

Zhu, Wei-hong; Zhang, Jin; Tong, Kai; Zhi, Guang; He, Kun-lun

2012-08-01

To determine the normal value of right ventricle using one beat full-volume real-time three-dimensional echocardiography (RT-3DE) and assess the feasibility of this technique. One beat full volume images were acquired at the apical 4 chamber view in 129 healthy volunteers. The right and left ventricular volumes were examined with the eSie LVA and RVA. The subjects were divided into 2 gender groups (male and female) and 3 age groups (20 - 39 years old, 40 - 59 years old, 60 years old and above). Adequate data were obtained in 129 subjects. The RV-EDV was (92.4 ± 21.3) ml, RV-ESV (34.6 ± 9.2) ml, RV-SV (57.8 ± 13.9) ml, RV-EF (62.5 ± 5.0) ml. EDV, ESV, and EF were significant different while SV was similar between RV and LV (all P Right ventricle function can be measured noninvasively by RT-3DE with high feasibility. This novel method contributes to the detailed study of right heart function in various cardiovascular diseases.

Cardiovascular performance of adult breeding sows fails to obey allometric scaling laws.

Science.gov (United States)

van Essen, G J; Vernooij, J C M; Heesterbeek, J A P; Anjema, D; Merkus, D; Duncker, D J

2011-02-01

In view of the remarkable decrease of the relative heart weight (HW) and the relative blood volume in growing pigs, we investigated whether HW, cardiac output (CO), and stroke volume (SV) of modern growing pigs are proportional to BW, as predicted by allometric scaling laws: HW (or CO or SV) = a·BW(b), in which a and b are constants, and constant b is a multiple of 0.25 (quarter-power scaling law). Specifically, we tested the hypothesis that both HW and CO scale with BW to the power of 0.75 (HW or CO = a·BW(0.75)) and SV scales with BW to the power of 1.00 (SV = a·BW(1.0)). For this purpose, 2 groups of pigs (group 1, consisting of 157 pigs of 50 ± 1 kg; group 2, consisting of 45 pigs of 268 ± 18 kg) were surgically instrumented with a flow probe or a thermodilution dilution catheter, under open-chest anesthetized conditions to measure CO and SV, after which HW was determined. The 95% confidence intervals of power-coefficient b for HW were 0.74 to 0.80, encompassing the predicted value of 0.75, suggesting that HW increased proportionally with BW, as predicted by the allometric scaling laws. In contrast, the 95% confidence intervals of power-coefficient b for CO and SV as measured with flow probes were 0.40 to 0.56 and 0.39 to 0.61, respectively, and values obtained with the thermodilution technique were 0.34 to 0.53 and 0.40 to 0.62, respectively. Thus, the 95% confidence limits failed to encompass the predicted values of b for CO and SV of 0.75 and 1.0, respectively. In conclusion, although adult breeding sows display normal heart growth, cardiac performance appears to be disproportionately low for BW. This raises concern regarding the health status of adult breeding sows.

A physical model study of the travel times and conversion point locations of P-SV converted waves in vertical transversely isotropic media

Science.gov (United States)

Tseng, C.

2013-12-01

In exploration seismology, subsurface medium commonly exhibits anisotropy, characterized by a vertical transversely isotropic (VTI) model. Due to the need of exploring small reservoirs in complex structures, the seismic exploration is extended to deal with anisotropic media. The P-S converted wave seismic exploration is a relatively inexpensive, broadly applicable, and effective way to obtain the S-wave information of the medium. In anisotropic traveltime analysis, the moveout curve of horizontal P-SV event can help to determine the ratio of the P- and SV-wave vertical velocities, the normal moveout (NMO) velocity of SV-waves, and the anisotropy parameters. The P-SV conversion point (CP) location is of great importance to P-SV data binning, NMO corrections and common conversion point (CCP) stacking, and the anisotropy has a more significant effect on the conversion point location than on the moveout. In this study, we attempt to inspect the theoretical non-hyperbolic moveout and CP equations for the P-SV waves reflected from a VTI layer by numerical calculations and physical modeling. We are also interested in visualizing the variations of the conversion point locations from a designed VTI medium. In traveltime analysis, the theoretical moveout curve is accurate up to offsets about one and a half times the reflector depth (x/z=1.5). However, the moveout curve computed by Fermat's principle fits well to the physical data. The CP locations of P-SV waves are similar to those calculated by Fermat's principle and theoretical CP equation, which are verified by the physical modeling.

Hip Hop Stroke: Study Protocol for a Randomized Controlled Trial to Address Stroke Literacy.

Science.gov (United States)

Williams, Olajide; Leighton-Herrmann, Ellyn; DeSorbo, Alexandra; Hecht, Mindy; Hedmann, Monique; Huq, Saima; Gerin, William; Chinchilli, Vernon; Ogedegbe, Gbenga; Noble, James

2015-10-01

Stroke is the fifth leading cause of death and the leading cause of serious long-term adult disability in the US. Acute stroke treatments with intravenous thrombolysis and endovascular therapy are proven to reduce disability, however a critical limitation on their effectiveness is the narrow time window for administration, which is 4.5 hours and 6 hours respectively from the onset of symptoms. Our overarching goal is to reduce pre-hospital delays to acute stroke treatments in economically disadvantaged minority communities where the greatest delays exist, using Hip Hop Stroke. Hip Hop Stroke (HHS) is a school-based, child-mediated, culturally-tailored stroke communication multimedia intervention developed using validated models of behavior change and designed to improve stroke literacy (knowledge of stroke symptoms, the urgent need to call 911, and prevention measures) of 4 th , 5 th and 6 th grade students and their parents residing in poor urban communities. Children in the intervention arm will receive the HHS intervention, while those in the attentional control arm will receive standardized nutrition education based on the USDA's MyPyramid program. Children will be trained and motivated to share stroke information with their parents or other adult caregiver. Both children and parents will complete a stroke knowledge assessment at baseline, immediately following the program, and at 3-months post-program. The primary outcome is the effect of the child mediation on parental stroke literacy. Stroke literate children, a captive audience in school systems, may represent a viable channel for spreading stroke information into households of poor urban communities where mass media stroke campaigns have shown the lowest penetration. These children may also call 911 when witnessing a stroke in their homes or communities. The HHS program may highlight the potential role of children in the chain of stroke recovery as a strategy for reducing prehospital delays to acute stroke

Prostate and seminal vesicle volume based consideration of prostate cancer patients for treatment with 3D-conformal or intensity-modulated radiation therapy

International Nuclear Information System (INIS)

Reddy, Nandanuri M. S.; Nori, Dattatreyudu; Chang, Hyesook; Lange, Christopher S.; Ravi, Akkamma

2010-01-01

Purpose: The purpose of this article was to determine the suitability of the prostate and seminal vesicle volumes as factors to consider patients for treatment with image-guided 3D-conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT), using common dosimetry parameters as comparison tools. Methods: Dosimetry of 3D and IMRT plans for 48 patients was compared. Volumes of prostate, SV, rectum, and bladder, and prescriptions were the same for both plans. For both 3D and IMRT plans, expansion margins to prostate+SV (CTV) and prostate were 0.5 cm posterior and superior and 1 cm in other dimensions to create PTV and CDPTV, respectively. Six-field 3D plans were prepared retrospectively. For 3D plans, an additional 0.5 cm margin was added to PTV and CDPTV. Prescription for both 3D and IMRT plans was the same: 45 Gy to CTV followed by a 36 Gy boost to prostate. Dosimetry parameters common to 3D and IMRT plans were used for comparison: Mean doses to prostate, CDPTV, SV, rectum, bladder, and femurs; percent volume of rectum and bladder receiving 30 (V30), 50 (V50), and 70 Gy (V70), dose to 30% of rectum and bladder, minimum and maximum point dose to CDPTV, and prescription dose covering 95% of CDPTV (D95). Results: When the data for all patients were combined, mean dose to prostate and CDPTV was higher with 3D than IMRT plans (P 0.2). On average, among all cases, the minimum point dose was less for 3D-CRT plans and the maximum point dose was greater for 3D-CRT than for IMRT (P 0.1). V30 was less (P 0.2), and V70 was more (P 0.2). Mean dose to femurs was more with 3D than IMRT plans (P 3 (39/48), respectively (P 3 , respectively, would be suitable for 3D-CRT. Patients with prostate and prostate+SV volumes >65 and 85 cm 3 , respectively, might get benefit from IMRT.

B vitamins and magnetic resonance imaging-detected ischemic brain lesions in patients with recent transient ischemic attack or stroke: the VITAmins TO Prevent Stroke (VITATOPS) MRI-substudy.

Science.gov (United States)

Cavalieri, Margherita; Schmidt, Reinhold; Chen, Christopher; Mok, Vincent; de Freitas, Gabriel R; Song, Swithin; Yi, Qilong; Ropele, Stefan; Grazer, Anja; Homayoon, Nina; Enzinger, Christian; Loh, Katherine; Wong, Ka Sing Lawrence; Wong, Adrian; Xiong, Yunyun; Chang, Hui Meng; Wong, Meng Cheong; Fazekas, Franz; Eikelboom, John W; Hankey, Graeme J

2012-12-01

Elevated concentrations of homocysteine are associated with cerebral small vessel disease (CSVD). B-vitamin supplementation with folate and vitamins B12 and B6 reduces homocysteine concentrations. In a substudy of the VITAmins TO Prevent Stroke (VITATOPS) trial, we assessed the hypothesis that the addition of once-daily supplements of B vitamins would reduce the progression of CSVD-related brain lesions. A total of 359 patients with recent stroke or transient ischemic attack, who were randomly allocated to double-blind treatment with placebo or b vitamins, underwent brain MRI at randomization and after 2 years of B-vitamin supplementation. MR images were analyzed blinded to treatment allocation. Outcomes related to the prespecified hypothesis were progression of white matter hyperintensities and incident lacunes. We also explored the effect of B-vitamin supplementation on the incidence of other ischemic abnormalities. After 2 years of treatment with b vitamins or placebo, there was no significant difference in white matter hyperintensities volume change (0.08 vs 0.13 cm3; P=0.419) and incidence of lacunes (8.0% vs 5.9%, P=0.434; odds ratio=1.38). In a subanalysis of patients with MRI evidence of severe CSVD at baseline, b-vitamin supplementation was associated with a significant reduction in white matter hyperintensities volume change (0.3 vs 1.7 cm3; P=0.039). Daily B-vitamin supplementation for 2 years did not significantly reduce the progression of brain lesions resulting from presumed CSVD in all patients with recent stroke or transient ischemic attack but may do so in the subgroup of patients with recent stroke or transient ischemic attack and severe CSVD. http://vitatops.highway1.com.au/. Unique identifier: NCT00097669 and ISRCTN74743444.

Prevalence of stroke symptoms among stroke-free residents: first national data from Lebanon.

Science.gov (United States)

Farah, Rita; Zeidan, Rouba Karen; Chahine, Mirna N; Asmar, Roland; Chahine, Ramez; Salameh, Pascale; Hosseini, Hassan

2015-10-01

Stroke symptoms are common among people without a history of stroke or transient ischemic attack. Reported stroke symptoms may represent stroke episodes that failed to reach the threshold for clinical diagnosis. This study aimed to assess in the Lebanese population the prevalence of self-reported stroke symptoms in a stroke- and transient ischemic attack-free population, and the association of these symptoms with major risk factors for stroke. We carried out a cross-sectional study using a multistage cluster sample across Lebanon. We interviewed residents aged 40 years and more. Stroke symptoms were assessed using the Questionnaire for Verifying Stroke-Free Status. We included 1515 individuals (mean age was 57·2 ± 12·4 years, 783 women, 51·7%). Among 1460 participants stroke- and transient ischemic attack-free, 175 had experienced at least one stroke symptom (12·1%, 95% CI 9·9%-14·3%). Arterial hypertension (adjOR 4·37, 95% CI 2·68-7·12), history of heart disease (adjOR 3·34, 95% CI 2·00-5·56), current waterpipe smoking (adjOR 3·88, 95% CI 2·33-6·48), current and former cigarette smoking (adjOR 1·84, 95% CI 1·18-2·87 and adjOR 2·01, 95% CI 1·13-3·5, respectively), psychological distress (adjOR 1·04, 95% CI 1·02-1·05), the Mediterranean diet score (adjOR 0·87, 95% CI 0·76-0·99), and regular physical activity (adjOR 0·45, 95% CI 0·26-0·77) were independently associated with stroke symptoms. This is the first study conducted in the Middle East, assessing self-reported stroke symptoms among stroke-free residents. Our study showed that almost one in eight residents without a history of stroke or transient ischemic attack has had stroke symptoms. Major vascular risk factors are associated with these symptoms, thus allowing for prevention strategies. © 2015 World Stroke Organization.

Self-Reported Stroke Risk Stratification: Reasons for Geographic and Racial Differences in Stroke Study.

Science.gov (United States)

Howard, George; McClure, Leslie A; Moy, Claudia S; Howard, Virginia J; Judd, Suzanne E; Yuan, Ya; Long, D Leann; Muntner, Paul; Safford, Monika M; Kleindorfer, Dawn O

2017-07-01

The standard for stroke risk stratification is the Framingham Stroke Risk Function (FSRF), an equation requiring an examination for blood pressure assessment, venipuncture for glucose assessment, and ECG to determine atrial fibrillation and heart disease. We assess a self-reported stroke risk function (SRSRF) to stratify stroke risk in comparison to the FSRF. Participants from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) were evaluated at baseline and followed for incident stroke. The FSRF was calculated using directly assessed stroke risk factors. The SRSRF was calculated from 13 self-reported questions to exclude those with prevalent stroke and assess stroke risk. Proportional hazards analysis was used to assess incident stroke risk using the FSRF and SRSRF. Over an average 8.2-year follow-up, 939 of 23 983 participants had a stroke. The FSRF and SRSRF produced highly correlated risk scores ( r Spearman =0.852; 95% confidence interval, 0.849-0.856); however, the SRSRF had higher discrimination of stroke risk than the FSRF (c SRSRF =0.7266; 95% confidence interval, 0.7076-0.7457; c FSRF =0.7075; 95% confidence interval, 0.6877-0.7273; P =0.0038). The 10-year stroke risk in the highest decile of predicted risk was 11.1% for the FSRF and 13.4% for the SRSRF. A simple self-reported questionnaire can be used to identify those at high risk for stroke better than the gold standard FSRF. This instrument can be used clinically to easily identify individuals at high risk for stroke and also scientifically to identify a subpopulation enriched for stroke risk. © 2017 American Heart Association, Inc.

Effect of a provincial system of stroke care delivery on stroke care and outcomes

Science.gov (United States)

Kapral, Moira K.; Fang, Jiming; Silver, Frank L.; Hall, Ruth; Stamplecoski, Melissa; O’Callaghan, Christina; Tu, Jack V.

2013-01-01

Background: Systems of stroke care delivery have been promoted as a means of improving the quality of stroke care, but little is known about their effectiveness. We assessed the effect of the Ontario Stroke System, a province-wide strategy of regionalized stroke care delivery, on stroke care and outcomes in Ontario, Canada. Methods: We used population-based provincial administrative databases to identify all emergency department visits and hospital admissions for acute stroke and transient ischemic attack from Jan. 1, 2001, to Dec. 31, 2010. Using piecewise regression analyses, we assessed the effect of the full implementation of the Ontario Stroke System in 2005 on the proportion of patients who received care at stroke centres, and on rates of discharge to long-term care facilities and 30-day mortality after stroke. Results: We included 243 287 visits by patients with acute stroke or transient ischemic attack. The full implementation of the Ontario Stroke System in 2005 was associated with an increase in rates of care at stroke centres (before implementation: 40.0%; after implementation: 46.5%), decreased rates of discharge to long-term care facilities (before implementation: 16.9%; after implementation: 14.8%) and decreased 30-day mortality for hemorrhagic (before implementation: 38.3%; after implementation: 34.4%) and ischemic stroke (before implementation: 16.3%; after implementation: 15.7%). The system’s implementation was also associated with marked increases in the proportion of patients who received neuroimaging, thrombolytic therapy, care in a stroke unit and antithrombotic therapy. Interpretation: The implementation of an organized system of stroke care delivery was associated with improved processes of care and outcomes after stroke. PMID:23713072

Automated detection of acute haemorrhagic stroke in non-contrasted CT images

International Nuclear Information System (INIS)

Meetz, K.; Buelow, T.

2007-01-01

An efficient treatment of stroke patients implies a profound differential diagnosis that includes the detection of acute haematoma. The proposed approach provides an automated detection of acute haematoma, assisting the non-stroke expert in interpreting non-contrasted CT images. It consists of two steps: First, haematoma candidates are detected applying multilevel region growing approach based on a typical grey value characteristic. Second, true haematomas are differentiated from partial volume artefacts, relying on spatial features derived from distance-based histograms. This approach achieves a specificity of 77% and a sensitivity of 89.7% in detecting acute haematoma in non-contrasted CT images when applied to a set of 25 non-contrasted CT images. (orig.)

White matter changes in stroke patients. Relationship with stroke subtype and outcome

DEFF Research Database (Denmark)

Leys, D; Englund, E; Del Ser, T

1999-01-01

or white matter lesions or leukoencephalopathy or leukoaraiosis' and 'stroke or cerebral infarct or cerebral hemorrhage or cerebrovascular disease or transient ischemic attack (TIA)'. WMC, as defined radiologically, are present in up to 44% of patients with stroke or TIA and in 50% of patients...... of death or dependency, recurrent stroke of any type, cerebral bleeding under anticoagulation, myocardial infarction, and poststroke dementia. WMC in stroke patients are often associated with small-vessel disease and lead to a higher risk of death, and poor cardiac and neurological outcome. However......White matter changes (WMC), detected by imaging techniques, are frequent in stroke patients. The aim of the study was to determine how WMC relate to stroke subtypes and to stroke outcome. We made a systematic Medline search for articles appearing with two of the following key words: either 'WMC...

Knowledge of stroke among stroke patients and their relatives in Northwest India.

Science.gov (United States)

Pandian, Jeyaraj Durai; Kalra, Guneet; Jaison, Ashish; Deepak, Sukhbinder Singh; Shamsher, Shivali; Singh, Yashpal; Abraham, George

2006-06-01

The knowledge of warning symptoms and risk factors for stroke has not been studied among patients with stroke in developing countries. We aimed to assess the knowledge of stroke among patients with stroke and their relatives. Prospective tertiary referral hospital-based study in Northwest India. Trained nurses and medical interns interviewed patients with stroke and transient ischemic attack and their relatives about their knowledge of stroke symptoms and risk factors. Univariable and multivariable logistic regression were used. Of the 147 subjects interviewed, 102 (69%) were patients and 45 (31%) were relatives. There were 99 (67%) men and 48 (33%) women and the mean age was 59.7+/-14.1 years. Sixty-two percent of respondents recognized paralysis of one side as a warning symptom and 54% recognized hypertension as a risk factor for stroke. In the multivariable logistic regression analysis, higher education was associated with the knowledge of correct organ involvement in stroke (OR 2.6, CI 1.1- 6.1, P =0.02), whereas younger age (OR 2.7, CI 1.1-7.0, P =0.04) and higher education (OR 4.1, CI 1.5-10.9, P =0.005) correlated with a better knowledge regarding warning symptoms of stroke. In this study cohort, in general, there is lack of awareness of major warning symptoms, risk factors, organ involvement and self-recognition of stroke. However younger age and education status were associated with better knowledge. There is an urgent need for awareness programs about stroke in this study cohort.

Methionine sulfoximine supplementation enhances productivity in GS-CHOK1SV cell lines through glutathione biosynthesis.

Science.gov (United States)

Feary, Marc; Racher, Andrew J; Young, Robert J; Smales, C Mark

2017-01-01

In Lonza Biologics' GS Gene Expression System™, recombinant protein-producing GS-CHOK1SV cell lines are generated by transfection with an expression vector encoding both GS and the protein product genes followed by selection in MSX and glutamine-free medium. MSX is required to inhibit endogenous CHOK1SV GS, and in effect create a glutamine auxotrophy in the host that can be complemented by the expression vector encoded GS in selected cell lines. However, MSX is not a specific inhibitor of GS as it also inhibits the activity of GCL (a key enzyme in the glutathione biosynthesis pathway) to a similar extent. Glutathione species (GSH and GSSG) have been shown to provide both oxidizing and reducing equivalents to ER-resident oxidoreductases, raising the possibility that selection for transfectants with increased GCL expression could result in the isolation of GS-CHOKISV cell lines with improved capacity for recombinant protein production. In this study we have begun to address the relationship between MSX supplementation, the amount of intracellular GCL subunit and mAb production from a panel of GS-CHOK1SV cell lines. We then evaluated the influence of reduced GCL activity on batch culture of an industrially relevant mAb-producing GS-CHOK1SV cell line. To the best of our knowledge, this paper describes for the first time the change in expression of GCL subunits and recombinant mAb production in these cell lines with the degree of MSX supplementation in routine subculture. Our data also shows that partial inhibition of GCL activity in medium containing 75 µM MSX increases mAb productivity, and its more specific inhibitor BSO used at a concentration of 80 µM in medium increases the specific rate of mAb production eight-fold and the concentration in harvest medium by two-fold. These findings support a link between the inhibition of glutathione biosynthesis and recombinant protein production in industrially relevant systems and provide a process-driven method for

Incidence of DWI-positive stroke in patients with vertigo of unclear etiology, preliminary results.

Science.gov (United States)

Leker, Ronen R; Hur, Tamir Ben; Gomori, John M; Paniri, R; Eichel, Roni; Cohen, Jose E

2013-03-01

Acute vertigo may be secondary to stroke or to non-ischemic causes. Accurate identification of vertigo secondary to ischemia may lead to appropriate timely intervention that can minimize stroke-related damage and can help in tailoring the most appropriate individual therapy for affected patients. Diffusion weighted MRI (DWI) is very accurate for diagnosing stroke and we therefore aimed to test whether it can aid in making a correct diagnosis of vertigo secondary to stroke. All patients presenting with vertigo in which the diagnosis of stroke was considered underwent DWI only MRI. Data regarding the symptoms and neurological deficits, vascular risk factors, imaging findings, and outcomes was accrued. Patients with stroke on DWI were compared with those without ischemia. Between June 2010 and August 2011, 28 patients fulfilling the entry criteria were identified with a mean age of 62·2±12·8 (60% male). The final diagnosis was stroke in 11 patients (39%). Patients with stroke did not differ from those without stroke in their risk factor profile. However, patients with stroke more often tended to present with vertigo accompanied by other neurological symptoms (73% versus 12% respectively, P = 0·001). After adjusting for age and the presence of diabetes, the presence of multiple symptoms remained the only variable that was associated with a positive DWI scan (odds ratio: 30: 95% confidence interval: 2·6-349). Most patients with stroke had very mild strokes with a median admission NIHSS score of 3 and DWI lesion volumes >2 cm were found in only three patients. Most stroke patients made a good recovery (modified Rankin score ≤2 in seven of nine patients with 90 day data). The most common diagnosis in patients without stroke was of vertigo of peripheral origin (14/17). DWI only MRI can be used to rapidly screen patients presenting with vertigo and suspected vertebrobasilar stroke. The occurrence of vertigo in combination with other focal neurological symptoms may

Exacerbation of Brain Injury by Post-Stroke Exercise Is Contingent Upon Exercise Initiation Timing

Directory of Open Access Journals (Sweden)

Fengwu Li

2017-10-01

Full Text Available Accumulating evidence has demonstrated that post-stroke physical rehabilitation may reduce morbidity. The effectiveness of post-stroke exercise, however, appears to be contingent upon exercise initiation. This study assessed the hypothesis that very early exercise exacerbates brain injury, induces reactive oxygen species (ROS generation, and promotes energy failure. A total of 230 adult male Sprague-Dawley rats were subjected to middle cerebral artery (MCA occlusion for 2 h, and randomized into eight groups, including two sham injury control groups, three non-exercise and three exercise groups. Exercise was initiated after 6 h, 24 h and 3 days of reperfusion. Twenty-four hours after completion of exercise (and at corresponding time points in non-exercise controls, infarct volumes and apoptotic cell death were examined. Early brain oxidative metabolism was quantified by examining ROS, ATP and NADH levels 0.5 h after completion of exercise. Furthermore, protein expressions of angiogenic growth factors were measured in order to determine whether post-stroke angiogenesis played a role in rehabilitation. As expected, ischemic stroke resulted in brain infarction, apoptotic cell death and ROS generation, and diminished NADH and ATP production. Infarct volumes and apoptotic cell death were enhanced (p < 0.05 by exercise that was initiated after 6 h of reperfusion, but decreased by late exercise (24 h, 3 days. This exacerbated brain injury at 6 h was associated with increased ROS levels (p < 0.05, and decreased (p < 0.05 NADH and ATP levels. In conclusion, very early exercise aggravated brain damage, and early exercise-induced energy failure with ROS generation may underlie the exacerbation of brain injury. These results shed light on the manner in which exercise initiation timing may affect post-stroke rehabilitation.

Burden of stroke in Bangladesh.

Science.gov (United States)

Islam, Md Nazmul; Moniruzzaman, Mohammed; Khalil, Md Ibrahim; Basri, Rehana; Alam, Mohammad Khursheed; Loo, Keat Wei; Gan, Siew Hua

2013-04-01

Stroke is the third leading cause of death in Bangladesh. The World Health Organization ranks Bangladesh's mortality rate due to stroke as number 84 in the world. The reported prevalence of stroke in Bangladesh is 0.3%, although no data on stroke incidence have been recorded. Hospital-based studies conducted in past decades have indicated that hypertension is the main cause of ischaemic and haemorrhagic stroke in Bangladesh. The high number of disability-adjusted life-years lost due to stroke (485 per 10,000 people) show that stroke severely impacts Bangladesh's economy. Although two non-governmental organizations, BRAC and the Centre for the Rehabilitation of the Paralysed, are actively involved in primary stroke prevention strategies, the Bangladeshi government needs to emphasize healthcare development to cope with the increasing population density and to reduce stroke occurrence. © 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.

Pre-stroke use of beta-blockers does not affect ischaemic stroke severity and outcome

NARCIS (Netherlands)

De Raedt, S.; Haentjens, P.; De Smedt, A.; Brouns, R.; Uyttenboogaart, Maarten; Luijckx, G. J.; De Keyser, J.

Background and purpose: It is unclear whether pre-stroke beta-blockers use may influence stroke outcome. This study evaluates the independent effect of pre-stroke use of beta-blockers on ischaemic stroke severity and 3 months functional outcome. Methods: Pre-stroke use of beta-blockers was