WorldWideScience

Sample records for blood volume expansion

  1. Effect of volume expansion on systemic hemodynamics and central and arterial blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Bendtsen, F; Henriksen, Jens Henrik Sahl

    1995-01-01

    BACKGROUND & AIMS: Systemic vasodilatation in cirrhosis may lead to hemodynamic alterations with reduced effective blood volume and decreased arterial blood pressure. This study investigates the response of acute volume expansion on hemodynamics and regional blood volumes in patients with cirrhosis...... and in controls. METHODS: Thirty-nine patients with cirrhosis (12 patients with Child-Turcotte class A, 14 with class B, and 13 with class C) and 6 controls were studied. During hepatic vein catheterization, cardiac output, systemic vascular resistance, central and arterial blood volume, noncentral...... change was found in patients with either class B or class C. Conversely, the noncentral blood volume increased in patients with class B and C. In both patients and controls, the cardiac output increased and the systemic vascular resistance decreased, whereas the mean arterial blood pressure did not...

  2. Acute blood volume expansion delays the gastrointestinal transit of a charcoal meal in awake rats

    Directory of Open Access Journals (Sweden)

    de-Oliveira G.R.

    1998-01-01

    Full Text Available The present study evaluates the effect of blood volume expansion on the gastrointestinal transit of a charchoal meal (2.5 ml of an aqueous suspension consisting of 5% charcoal and 5% gum arabic in awake male Wistar rats (200-270 g. On the day before the experiments, the rats were anesthetized with ether, submitted to left jugular vein cannulation and fasted with water ad libitum until 2 h before the gastrointestinal transit measurement. Blood volume expansion by iv infusion of 1 ml/min Ringer bicarbonate in volumes of 3, 4 or 5% body weight delayed gastrointestinal transit at 10 min after test meal administration by 21.3-26.7% (P<0.05, but no effect was observed after 1 or 2% body weight expansion. The effect of blood volume expansion (up to 5% body weight on gastrointestinal transit lasted for at least 60 min (P<0.05. Mean arterial pressure increased transiently and central venous pressure increased and hematocrit decreased (P<0.05. Subdiaphragmatic vagotomy and yohimbine (3 mg/kg prevented the delay caused by expansion on gastrointestinal transit, while atropine (0.5 mg/kg, L-NAME (2 mg/kg, hexamethonium (10 mg/kg, prazosin (1 mg/kg or propranolol (2 mg/kg were ineffective. These data show that blood volume expansion delays the gastrointestinal transit of a charcoal meal and that vagal and yohimbine-sensitive pathways appear to be involved in this phenomenon. The delay in gastrointestinal transit observed here, taken together with the modifications of gastrointestinal permeability to salt and water reported by others, may be part of the mechanisms involved in liquid excess management.

  3. Altitude acclimatization and blood volume: effects of exogenous erythrocyte volume expansion

    DEFF Research Database (Denmark)

    Sawka, M N; Young, Jette Feveile; Rock, P B;

    1996-01-01

    blood oxygen content alters erythropoietin responses during altitude acclimatization, and 4) mechanisms responsible for plasma loss at altitude. Sixteen healthy men had a series of hematologic measurements made at sea level, on the first and ninth days of altitude (4,300 m) residence, and after...

  4. Backward volume contraction for endomorphisms with eventual volume expansion

    OpenAIRE

    Pinheiro, Vilton; Castro, Armando; Alves, J. F.

    2009-01-01

    We consider smooth maps on compact Riemannian manifolds. We prove that under some mild condition of eventual volume expansion Lebesgue almost everywhere we have uniform backward volume contraction on every pre-orbit for Lebesgue almost every point.

  5. Cardiorenal-endocrine dynamics during and following volume expansion

    International Nuclear Information System (INIS)

    The relationship between atrial pressure, atrial natriuretic peptide (ANP), the renin-angiotensin-aldosterone system, and renal hemodynamic and excretory function was examined during and following acute 10% body weight saline volume expansion and measurements were made at 3.3, 6.6, and 10% body weight volume expansion in pentobarbital anesthetized dogs. Right atrial pressure (RAP), pulmonary capillary wedge pressure (PCWP), fractional excretion of Na (FE/sub Na/), and ANP all increased in parallel during volume expansion. Plasma renin activity (PRA) and aldosterone decreased in parallel during 10% volume expansion. ANP, PRA and aldosterone were measured by radioimmunoassay. Following 10% volume expansion, saline was infused at the peak urine flow rate to maintain peak volume expansion. Despite continued saline infusion, RAP, PCWP, and ANP decreased in parallel. In contrast, FE/sub Na/ remained increased, and aldosterone and PRA remained depressed. These studies demonstrate that atrial pressures, ANP, and FE/sub Na/ increase in parallel during volume expansion; this suggests a role for ANP in modulating acute atrial volume overload. During stable volume expansion periods, however, despite a decrease in ANP levels, Na excretion remains elevated, suggesting that non-ANP mechanisms may be important in maintaining natriuresis during stable volume expansion

  6. Reduced central blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Bendtsen, F; Henriksen, Jens Henrik Sahl; Sørensen, T I; Stadeager, C; Ring-Larsen, H

    1989-01-01

    The pathogenesis of ascites formation in cirrhosis is uncertain. It is still under debate whether the effective blood volume is reduced (underfilling theory) or whether the intravascular compartment is expanded (overflow theory). This problem has not yet been solved because of insufficient tools...... for measuring the central blood volume. We have developed a method that enables us to determine directly the central blood volume, i.e., the blood volume in the heart cavities, lungs, and central arterial tree. In 60 patients with cirrhosis and 16 control subjects the central blood volume was assessed...... according to the kinetic theory as the product of cardiac output and mean transit time of the central vascular bed. Central blood volume was significantly smaller in patients with cirrhosis than in controls (mean 21 vs. 27 ml/kg estimated ideal body weight, p less than 0.001; 25% vs. 33% of the total blood...

  7. Reduced central blood volume in cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Bendtsen, Flemming; Sørensen, T I;

    1989-01-01

    was inversely correlated to the systemic vascular resistance (r = -0.49, p less than 0.001), the latter being significantly reduced in the patient group. Patients with cirrhosis apparently are unable to maintain a normal central blood volume. This may be due to arteriolar vasodilation, portosystemic collateral......The pathogenesis of ascites formation in cirrhosis is uncertain. It is still under debate whether the effective blood volume is reduced (underfilling theory) or whether the intravascular compartment is expanded (overflow theory). This problem has not yet been solved because of insufficient tools...... for measuring the central blood volume. We have developed a method that enables us to determine directly the central blood volume, i.e., the blood volume in the heart cavities, lungs, and central arterial tree. In 60 patients with cirrhosis and 16 control subjects the central blood volume was assessed according...

  8. Volume expansion of a Swiss-cheese universe

    International Nuclear Information System (INIS)

    In order to investigate the effect of inhomogeneities on the volume expansion of the universe, we study a modified Swiss-cheese universe model. Since this model is an exact solution of Einstein's equations, we can get insight into the nonlinear dynamics of an inhomogeneous universe from it. We find that inhomogeneities make the volume expansion slower than that of the background Einstein-de Sitter universe when they can be regarded as small fluctuations in the background universe. This result is consistent with the previous studies based on the second order perturbation analysis. On the other hand, if the inhomogeneities cannot be treated as small perturbations, the volume expansion of the universe depends on the type of fluctuations. Although the volume expansion rate approaches the background value asymptotically, the volume itself can be finally arbitrarily smaller than the background one and can be larger than that of the background, but there is an upper bound on it

  9. On the thermal expansion of nanohole free volume in perfluoropolyethers.

    Science.gov (United States)

    Consolati, G

    2005-05-26

    To determine the free volume in polymers, positron annihilation lifetime spectroscopy data are transformed into nanohole volumes by modeling the cavities as spheres or, more generally, using geometries assuming an isotropic thermal expansion. However, this guess could be unrealistic owing to the irregular shape of nanoholes and constrained movements of the macromolecules. In this work, it is shown that a comparison of hole-lattice theory with positron and dilatometric data for a homologous series of perfluoropolyethers supplies information on the anisotropic expansion of nanoholes; the relation between volume and typical unconstrained size of the cavities can be expressed by a power law with noninteger exponents. PMID:16852223

  10. Changes in circulating blood volume after infusion of hydroxyethyl starch 6% in critically ill patients

    DEFF Research Database (Denmark)

    Christensen, P; Andersson, J; Rasmussen, S E; Andersen, P K; Henneberg, S W

    2001-01-01

    The cardiovascular response to a volume challenge with hydroxyethyl starch (HES) (200/0.5) 6% depends on the relation between the volume of HES 6% infused and the expansion of the blood volume in critically ill patients. However, only relatively limited data exist on the plasma expanding effect o...... infusion of HES 6% in critically ill patients. The purpose of the study was to evaluate the variation in the expansion of the circulating blood volume (CBV) in critically ill patients after infusion of 500 ml of colloid (HES (200/0.5) 6%) using the carbon monoxide method.......The cardiovascular response to a volume challenge with hydroxyethyl starch (HES) (200/0.5) 6% depends on the relation between the volume of HES 6% infused and the expansion of the blood volume in critically ill patients. However, only relatively limited data exist on the plasma expanding effect of...

  11. Review article: volume expansion in patients with cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Kiszka-Kanowitz, Marianne; Bendtsen, Flemming

    2002-01-01

    Adequate size and distribution of the circulating medium are important for cardiovascular function, tissue oxygenation, and fluid homoeostasis. Patients with cirrhosis have cardiovascular dysfunction with a hyperkinetic systemic circulation, abnormal distribution of the blood volume, vasodilation...

  12. Changes in circulating blood volume after infusion of hydroxyethyl starch 6% in critically ill patients

    DEFF Research Database (Denmark)

    Christensen, P; Andersson, J; Rasmussen, S E;

    2001-01-01

    The cardiovascular response to a volume challenge with hydroxyethyl starch (HES) (200/0.5) 6% depends on the relation between the volume of HES 6% infused and the expansion of the blood volume in critically ill patients. However, only relatively limited data exist on the plasma expanding effect of...... infusion of HES 6% in critically ill patients. The purpose of the study was to evaluate the variation in the expansion of the circulating blood volume (CBV) in critically ill patients after infusion of 500 ml of colloid (HES (200/0.5) 6%) using the carbon monoxide method....

  13. Photoplethysmographic variability: spontaneous fluctuations in the tissue blood volume and in the systolic blood volume increase

    Science.gov (United States)

    Nitzan, Meir; Babchenko, Anatoly; Turivnenko, Sergei; Khanokh, Boris

    1997-05-01

    Several parameters of the cardiovascular system such as heart rate, arterial blood pressure and blood flow fluctuate spontaneously due to the autonomic nervous system activity. In the current study, the low frequency fluctuations of the tissue blood volume and the blood volume pulse in the fingertips of healthy subjects were investigated using transmission photoplethysmography (PPG). The baseline of the PPG signal (BL) is inversely related to tissue blood volume so that the parameter BV, defined by: BV equals Const.-BL is directly related to the blood volume. The amplitude (AM) is directly related to the systolic blood volume increase. For most of the examinations BV and AM show positive correlation, which is expected since BV depends on the tissue blood volume and AM depends on the compliance of the blood vessels, both of which decrease during vasoconstriction, which is caused by higher activity of the sympathetic nervous system. The analysis of the PPG signal provides, therefore, a potential tool for study in the mechanism of the regulation of the microcirculation by the sympathetic nerves.

  14. Increased ANF secretion after volume expansion is preserved in rats with heart failure

    International Nuclear Information System (INIS)

    To examine whether the failing heart has reached a maximal capacity to increase plasma atrial natriuretic factor (ANF) concentration, the change in plasma immunoreactive ANF, measured by radioimmunoassay level due to acute blood volume expansion was determined in conscious rats with chronic heart failure. Varying degrees of myocardial infarction and thus heart failure were induced by coronary artery ligation 3 wk before study. Compared with controls, infarcted rats had decreases in mean arterial pressure cardiac index, renal blood flow, and peak left ventricle-developed pressure after aortic occlusion, and increases in central venous pressure, left ventricular end-diastolic pressure, total peripheral resistance, plasma ANF level. Plasma ANF was correlated with infarct size, cardiac filling pressures, and left ventricle pressure-generating ability. At 5 min after 25% blood volume expansion, plasma ANF in rats with heart failure increased by 2,281 ± 345 pg/ml; the magnitude of the changes in circulating ANF and hemodynamic measurements was similar in controls. The results suggest that plasma ANF level can be used as a reliable index of the severity of heart failure, and that the capacity to increase plasma ANF concentration after acute volume expansion is preserved in rats with heart failure. There was no evidence of a relative deficiency of circulating ANF in this model of heart failure

  15. Volume reduction in routine cord blood banking.

    Science.gov (United States)

    Solves, Pilar; Mirabet, Vicente; Roig, Roberto

    2010-12-01

    Umbilical cord blood (UCB) is an alternative source of hematopoietic progenitors for transplantation in the treatment of haematological malignancies, marrow failure, immunodeficiencies, hemoglobinopathies and inherited metabolic diseases. It has greatly contributed to increase the feasibility to transplantation for many patients in need. To date, more than 20,000 UCB transplants have been performed on children and adults, and more than 400,000 UCB units are available in more than 50 public CB banks. One of the most important objectives of banks is to cryopreserve and store high quality UCB units. Volume reduction is a usual process in cord blood banking that has some advantages as reducing the storage space and the DMSO quantity in final product. Volume reduction methodology must guarantee high cell recovery and red blood cell (RBC) depletion by reducing the UCB units to a standard volume. Hydroxyethyl starch (HES) sedimentation was the first method developed for this purpose by the New York Cord Blood Bank and implemented in many banks worldwide. The semi-automated top and bottom system, usually used for blood fractionation was further developed to simplify and short the process. Later, automatic devices as SEPAX and AXP have been developed in last years specifically for UCB volume reduction purpose. This review critically analyses the advantages and disadvantages of the different procedures. All of them have been used in Valencia Cord Blood Bank along 10 years. In general, automatic devices are preferred because of compliance with cGTP, closed systems, higher reproducibility and less influence of technician. PMID:20528760

  16. Noninvasive measurement of pulmonary blood volume

    International Nuclear Information System (INIS)

    In noninvasive estimation of pulmonary blood volume by radionuclide-angiocardiography, a formula was derived from experiments with heart-lung model, and in vivo experiments PBV = CO x PPT x 0.77. The pulmonary blood volume estimated clinically by this formula was in good agreement with the results obtained invasively before. The compliance (δV/δP) of the pulmonary ''venous'' system was calculated by simultaneous measurement of pressure changes in lung field on leg elevation and changes in pulmonary arterial wedge pressure with Swan-Ganz catheter. The compliances which were calculated in 35 cases of heart diseases by this method were in a considerably good agreement with those which were assessed by analysis of a pulmonary arterial wedge pressure tracing. (Ueda, J.)

  17. On-line dialysate infusion to estimate absolute blood volume in dialysis patients.

    Science.gov (United States)

    Schneditz, Daniel; Schilcher, Gernot; Ribitsch, Werner; Krisper, Peter; Haditsch, Bernd; Kron, Joachim

    2014-01-01

    It was the aim to measure the distribution volume and the elimination of ultra-pure dialysate in stable hemodialysis patients during on-line hemodiafiltration (HDF). Dialysate was automatically infused as a volume indicator using standard on-line HDF equipment. Indicator concentration was noninvasively measured in the arterial blood-line (using the blood volume monitor, Fresenius Medical Care, Bad Homburg vor der Höhe, Germany), and its time course was analyzed to obtain the elimination rate and the distribution volume V(t) at the time of dilution. Blood volume at treatment start (V0) was calculated accounting for the degree of intradialytic hemoconcentration. Five patients (two females) were studied during 15 treatments. Two to six measurements using indicator volumes ranging from 60 to 210 ml were done in each treatment. V0 was 4.59 ± 1.15 L and larger than the volume of 4.08 ± 0.48 L estimated from anthropometric relationships. The mean half-life of infused volume was 17.2 ± 29.7 min. Given predialysis volume expansion V0 was consistent with blood volume determined from anthropometric measurements. Information on blood volume could substantially improve volume management in hemodialysis patients and fluid therapy in intensive care patients undergoing extracorporeal blood treatment. The system has the potential for complete automation using proper control inputs for BVM and HDF modules of the dialysis machine. PMID:24814842

  18. Neuroendocrine and renal effects of intravascular volume expansion in compensated heart failure

    DEFF Research Database (Denmark)

    Gabrielsen, A; Bie, P; Holstein-Rathlou, N H;

    2001-01-01

    To examine if the neuroendocrine link between volume sensing and renal function is preserved in compensated chronic heart failure [HF, ejection fraction 0.29 +/- 0.03 (mean +/- SE)] we tested the hypothesis that intravascular and central blood volume expansion by 3 h of water immersion (WI) elicits...... (by sustained angiotensin-converting enzyme inhibitor therapy, n = 9) absolute and fractional sodium excretion increased (P < 0.05) to the level of control subjects (108 +/- 34 micromol/min and 0.70 +/- 0.23%, respectively). Renal free water clearance increased during WI in control subjects but not in...... HF, albeit plasma vasopressin concentrations were similar in the two groups. In conclusion, the neuroendocrine link between volume sensing and renal sodium excretion is preserved in compensated HF. The natriuresis of WI is, however, modulated by the prevailing ANG II and Aldo concentrations. In...

  19. Finite-volume cumulant expansion in QCD-colorless plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ladrem, M. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); Physics Department, Algiers (Algeria); ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Ahmed, M.A.A. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Taiz University in Turba, Physics Department, Taiz (Yemen); Alfull, Z.Z. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); Cherif, S. [ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Ghardaia University, Sciences and Technologies Department, Ghardaia (Algeria)

    2015-09-15

    Due to the finite-size effects, the localization of the phase transition in finite systems and the determination of its order, become an extremely difficult task, even in the simplest known cases. In order to identify and locate the finite-volume transition point T{sub 0}(V) of the QCD deconfinement phase transition to a colorless QGP, we have developed a new approach using the finite-size cumulant expansion of the order parameter and the L{sub mn}-method. The first six cumulants C{sub 1,2,3,4,5,6} with the corresponding under-normalized ratios (skewness Σ, kurtosis κ, pentosis Π{sub ±}, and hexosis H{sub 1,2,3}) and three unnormalized combinations of them, (O = σ{sup 2}κΣ{sup -1},U = σ{sup -2}Σ{sup -1},N = σ{sup 2}κ) are calculated and studied as functions of (T, V). A new approach, unifying in a clear and consistent way the definitions of cumulant ratios, is proposed.Anumerical FSS analysis of the obtained results has allowed us to locate accurately the finite-volume transition point. The extracted transition temperature value T{sub 0}(V) agrees with that expected T{sub 0}{sup N}(V) from the order parameter and the thermal susceptibility χ{sub T} (T, V), according to the standard procedure of localization to within about 2%. In addition to this, a very good correlation factor is obtained proving the validity of our cumulants method. The agreement of our results with those obtained by means of other models is remarkable. (orig.)

  20. Finite Volume Cumulant Expansion in QCD-Colorless Plasma

    CERN Document Server

    Ladrem, M; Al-Full, Z; Cherif, S

    2015-01-01

    Due to the finite size effects, the localisation of the phase transition in finite systems and the determination of its order, become an extremely difficult task, even in the simplest known cases. In order to identify and locate the finite volume transition point $T_{0}(V)$ of the QCD deconfinement phase transition to a Colorless QGP, we have developed a new approach using the finite size cumulant expansion of the order parameter and the $L_{mn}$-method. The first six cumulants $C_{1,2,3,4,5,6}$ with the corresponding under-normalized ratios(skewness $\\Sigma$, kurtosis $\\kappa$ ,pentosis $\\Pi_{\\pm}$ and hexosis $\\mathcal{H}_{1,2,3}$) and three unnormalized combinations of them ($\\mathcal{O}={\\mathcal{\\sigma }^{2} \\mathcal{\\kappa } }{\\mathbf{\\Sigma }^{-1} }$, $\\mathcal{U} ={\\mathcal{\\sigma }^{-2} \\mathbf{\\Sigma }^{-1} }$, $\\mathcal{N} = \\mathcal{\\sigma }^{2} \\mathcal{\\kappa }$) are calculated and studied as functions of $(T,V)$. A new approach, unifying in a clear and consistent way the definitions of cumulant...

  1. External Volume Expansion Modulates Vascular Growth and Functional Maturation in a Swine Model

    Science.gov (United States)

    Kao, Huang-Kai; Hsu, Hsiang-Hao; Chuang, Wen-Yu; Chen, Sheng-Chih; Chen, Bin; Wu, Shinn-Chih; Guo, Lifei

    2016-01-01

    Despite increasing application of the pre-grafting expansion during autologous fat transplantation in breast reconstruction, little is known about its mechanism of action. To address that, ventral skins of miniature pigs were treated over a 10-day or 21-day period, with continuous suction at −50 mm Hg via a 7-cm diameter rubber-lined suction-cup device. Soft tissue thickness increased immediately after this external volume expansion (EVE) treatment, such increase completely disappeared by the next day. In the dermis and subcutaneous fat, the EVE treated groups showed significant increases in blood vessel density evident by CD31 staining as well as in vascular networks layered with smooth muscle cells when compared with the control group. This finding was corroborated by the increased percentage of endothelial cells present in the treatment groups. There was no significant difference in the percentages of proliferating basal keratinocytes or adipocytes, nor in epidermal thickness. Moreover, the EVE had no effect on proliferation or differentiation potential of adipose stem cells. Taken together, the major effects of EVE appeared to be vascular remodeling and maturation of functional blood vessels. This understanding may help clinicians optimize the vascularity of the recipient bed to further improve fat graft survival. PMID:27174509

  2. Determination of the blood volume of rabbits (1963)

    International Nuclear Information System (INIS)

    The knowledge of the ratio of the blood volume to the weight of an animal is of a great deal in various experiments. Therefore authors have decided to determine this ratio for rabbits by using chromium 51. Results show that the blood volume represents about 54.4 g per kilogram of body weight. (authors)

  3. Pulmonary blood volume measured by RI angiocardiography

    International Nuclear Information System (INIS)

    RI angiocardiography (RACG) was performed in 81 patients with heart disease without congestive heart failure at the time, and the results were compared between the groups with mitral valve disease and other diseases. Cardiac output (CO) and pulmonary mean transit time (PMTT) were compared with the results from the dye dilution method in the same patients. PMTT directly measured by RACG was also compared with the peak to peak time (P-PT). P-PT was expressed as the distance from the right to the left peak time in radiocardiography (RCG). There were good correlations between the CO and PMTT obtained from the RI method and those of the dye dilution method (r = 0.90, r = 0.84). The ralationship between PMTT and P-PT in mitral valve disease was different from that of other diseases. The average value of PMTT was 5.2 +- 1.0 seconds, and pulmonary blood volume (PBV) was 315 +- 57 ml/m2 in the control group. The PBV values were markedly increased in patients with mitral stenosis (558 +- 132 ml/m2) and mitral regurgitation (444 +- 119 ml/m2), and were slightly increased in aortic valve disease, congenital shunt disease and cardiomyopathy. The patients with ischemic heart disease had normal PBV. In mitral valve disease, the direct method using PMTT of RACG is more accurate than the presumption method using P-PT of RCG. The determination of PBV by this method is very important to observe hemodynamic states in mitral valve disease. (J.P.N.)

  4. Code development of the national hemovigilance system and expansion strategies for hospital blood banks

    Directory of Open Access Journals (Sweden)

    Kim Jeongeun

    2012-01-01

    Full Text Available Objectives : The aims of this study were to develop reportable event codes that are applicable to the national hemovigilance systems for hospital blood banks, and to present expansion strategies for the blood banks. Materials and Methods : The data were obtained from a literature review and expert consultation, followed by adding to and revising the established hemovigilance code system and guidelines to develop reportable event codes for hospital blood banks. The Medical Error Reporting System-Transfusion Medicine developed in the US and other codes of reportable events were added to the Korean version of the Biologic Products Deviation Report (BPDR developed by the Korean Red Cross Blood Safety Administration, then using these codes, mapping work was conducted. We deduced outcomes suitable for practice, referred to the results of the advisory councils, and conducted a survey with experts and blood banks practitioners. Results : We developed reportable event codes that were applicable to hospital blood banks and could cover blood safety - from blood product safety to blood transfusion safety - and also presented expansion strategies for hospital blood banks. Conclusion : It was necessary to add 10 major categories to the blood transfusion safety stage and 97 reportable event codes to the blood safety stage. Contextualized solutions were presented on 9 categories of expansion strategies of hemovigilance system for the hospital blood banks.

  5. Continuous monitoring of blood volume changes in humans

    Science.gov (United States)

    Hinghofer-Szalkay, H.; Greenleaf, J. E.

    1987-01-01

    Use of on-line high-precision mass densitometry for the continuous monitoring of blood volume changes in humans was demonstrated by recording short-term blood volume alterations produced by changes in body position. The mass density of antecubital venous blood was measured continuously for 80 min per session with 0.1 g/l precision at a flow rate of 1.5 ml/min. Additional discrete plasma density and hematocrit measurements gave linear relations between all possible combinations of blood density, plasma density, and hematocrit. Transient filtration phenomena were revealed that are not amenable to discontinuous measurements.

  6. On-line dynamic measurement of blood viscosity, hematocrit and change of blood volume

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To develop an on-line system for the measurement of blood viscosity and hematocrit. The dynamic changes of the macrovascular blood volumes,microvascular blood volumes and the total blood volume were observed by means of calculating from the testing result. Methods: Applying traditional viscosity measurement principle and specific wavelength optic density measurement method, an on-line system for the measurement of blood viscosity and hematocrit was developed, and the A/D multifunctionai board and the testing circuit were designed by ourselves. The system was validated by experiments both in vitro and in vivo. Therapeutic effects of hypertonic saline dextran solution (HSD) and Lactatic Ringer's solution at the early stage after burn-blast combined injury were compared by this method. Results: The results showed that the system has attained the goal of the design. The changes of the blood viscosity and hematocrit could be detected effectively and continuously. The changes of macrovascular, microvascular and total blood volume could be calculated approximately. Conclusions: The system and the method can continuously on-line test the blood viscosity and hematocrit, and reveal the change and distribution of blood volumes more accurately and dearly in the therapy process by estimating changes of the macrovascular, microvascular and total blood volumes, respectively. It has confirmed that HSD treatment could increase blood pressure and attenuate tissue edema by significantly increasing total blood volume,improving macrocirculatory and microcirculatory blood volumes. This study suggested that it could be desirable to develop an experiment technique based on the method mentioned above.

  7. F-Area Northeast Expansion Report, Volumes 1

    Energy Technology Data Exchange (ETDEWEB)

    Syms, F.H.

    1999-08-23

    A geotechnical program has been complexed in F-Area at the Savannah River Site in South Carolina. This program investigated the subsurface conditions for the area known as the ''northeast expansion'' located in the F-Area.

  8. Determination of blood volume by pulse CO-oximetry

    International Nuclear Information System (INIS)

    The objective of this study was to determine whether changes in carboxyhaemoglobin (COHb) saturation following carbon monoxide (CO) rebreathing can be accurately detected by pulse CO-oximetry in order to determine blood volume. Noninvasive measurements of carboxyhaemoglobin saturation (SpCO) were continuously monitored by pulse CO-oximetry before, during and following 2 min of CO rebreathing. Reproducibility and accuracy of noninvasive blood volume measurements were determined in 16 healthy non-smoking individuals (15 males, age: 28 ± 2 years, body mass index: 25.4 ± 0.6 kg m−2) through comparison with blood volume measurements calculated from invasive measurements of COHb saturation. The coefficient of variation for noninvasive blood volume measurements performed on separate days was 15.1% which decreases to 9.1% when measurements were performed on the same day. Changes in COHb saturation and SpCO following CO rebreathing were strongly correlated (r = 0.90, p < 0.01), resulting in a significant correlation between invasive and noninvasive blood volume measurements (r = 0.83, p = 0.02). Changes in SpCO following CO rebreathing can be accurately detected by pulse CO-oximetry, which could potentially provide a simplified, convenient and reproducible method to rapidly determine blood volume in healthy individuals

  9. RELATIVE BLOOD VOLUME: THE MEANS OF INTRADIALYSIS HYPOTENSION PREVENTION

    OpenAIRE

    V. A. Terehov; A. G. Strokov

    2010-01-01

    Intravascular volume preservation is the first choice measure for the prevention of intradialysis hypotension. At present there are devices that allow continuous monitoring of relative blood volume (RBV) changes during haemodialysis (HD). The aim of this research was to investigate (i) the regularity of RBV curve during haemo- dialysis and (ii) the efficacy of some measures for intravascular volume preservation. In patients with hyperhydration RBV curves were monotone; in all cases relation ...

  10. Intracranial volume changes following cranial vault expansion using distraction techniques in craniosynostosis

    International Nuclear Information System (INIS)

    From October 2000 through December 2004, 12 children with craniosynostosis were treated by cranial vault expansion using distraction techniques. Intracranial volumes were calculated from mathematical data of three-dimensional surface reconstruction computed tomographic scans obtained before and after cranial expansion. The intracranial volumes measured before surgery were compared with those after surgery to confirm quantitatively the effect of cranial expansion. These results were compared with those of 27 cases treated previously with conventional craniofacial surgery. Intracranial volumes increased by more than 20% with distraction techniques but increased by less than 10% with conventional craniofacial techniques. This result suggests that cranial vault expansion with distraction techniques is more useful than conventional craniofacial surgery in children with craniosynostosis. (author)

  11. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

    International Nuclear Information System (INIS)

    Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters

  12. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1977-09-01

    Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters. (LK)

  13. Small volume expansion of almost supersymmetric large N theories

    Energy Technology Data Exchange (ETDEWEB)

    Barbon, Jose L. F. [Instituto de Fisica Teorica C-XVI, UAM, Cantoblanco 28049. Madrid (Spain); Hoyos, Carlos [Instituto de Fisica Teorica C-XVI, UAM, Cantoblanco 28049. Madrid (Spain)

    2006-01-15

    We consider the small-volume dynamics of nonsupersymmetric orbifold and orientifold field theories defined on a three-torus, in a test of the claimed planar equivalence between these models and appropriate supersymmetric ''parent models{sup .} We study one-loop effective potentials over the moduli space of flat connections and find that planar equivalence is preserved for suitable averages over the moduli space. On the other hand, strong nonlinear effects produce local violations of planar equivalence at special points of moduli space. In the case of orbifold models, these effects show that the 'twisted' sector dominates the low-energy dynamics.

  14. Small volume expansion of almost supersymmetric large N theories

    International Nuclear Information System (INIS)

    We consider the small-volume dynamics of nonsupersymmetric orbifold and orientifold field theories defined on a three-torus, in a test of the claimed planar equivalence between these models and appropriate supersymmetric ''parent models. We study one-loop effective potentials over the moduli space of flat connections and find that planar equivalence is preserved for suitable averages over the moduli space. On the other hand, strong nonlinear effects produce local violations of planar equivalence at special points of moduli space. In the case of orbifold models, these effects show that the 'twisted' sector dominates the low-energy dynamics

  15. The determination of chromium-50 in human blood and its utilization for blood volume measurements

    International Nuclear Information System (INIS)

    Possible relationships between insufficient blood volume increases during pregnancy and infant mortality could be established with an adequate measurement procedure. An accurate and precise technique for blood volume measurements has been found in the isotope dilution technique using chromium-51 as a label for red blood cells. However, in a study involving pregnant women, only stable isotopes can be used for labeling. Stable chromium-50 can be determined in total blood samples before and after dilution experiments by neutron activation analysis (NAA) or mass spectrometry. However, both techniques may be affected by insufficient sensitivity and contamination problems at the inherently low natural chromium concentrations to be measured in the blood. NAA procedures involving irradiations with highly thermalized neutrons at a fluence rate of 2x1013 n/cm2xs and low background gamma spectrometry are applied to the analysis of total blood. Natural levels of chromium-50 in human and animal blood have been found to be <0.1 ng/mL; i.e., total chromium levels of <3 ng/mL. Based on the NAA procedure, a new approach to the blood volume measurement via chromium-50 isotope dilution has been developed which utilizes the ratio of the induced activities of chromium-51 to the iron-59 in three blood samples taken from each individual, namely blank, labeled and diluted labeled blood. (author)

  16. Volume thermal expansivity for lower mantle region of earth under adiabatic condition

    International Nuclear Information System (INIS)

    A reciprocal equation for the volume dependence of Anderson–Grüneisen parameter has been proposed. This equation has been found to fit the seismic data for the lower mantle region of the Earth. We have developed a new expression for predicting the values of density (volume) dependence of volume thermal expansivity under adiabatic conditions based on the reciprocal equation for the volume dependence of Anderson–Grüneisen parameter. It is found that our relationship fits well the seismic data on volume thermal expansivity for lower mantle corresponding to a wide range of pressures (0–135.75 GPa). These equations thus proposed are found to be consistent with the thermodynamic constraints

  17. External Volume Expansion Modulates Vascular Growth and Functional Maturation in a Swine Model

    OpenAIRE

    Kao, Huang-Kai; Hsu, Hsiang-Hao; Chuang, Wen-Yu; Chen, Sheng-Chih; Chen, Bin; Wu, Shinn-Chih; Guo, Lifei

    2016-01-01

    Despite increasing application of the pre-grafting expansion during autologous fat transplantation in breast reconstruction, little is known about its mechanism of action. To address that, ventral skins of miniature pigs were treated over a 10-day or 21-day period, with continuous suction at −50 mm Hg via a 7-cm diameter rubber-lined suction-cup device. Soft tissue thickness increased immediately after this external volume expansion (EVE) treatment, such increase completely disappeared by the...

  18. [Correlation between the regional blood volume and epileptic seizures in Papio papio].

    Science.gov (United States)

    Ancri, D; Naquet, R; Basset, J Y; Ménini, C; Lonchampt, M F; Meldrum, B S; Stutzmann, J M

    1979-07-16

    The method of labelling red cells with technetium-99m was used to measured regional blood volume auring different types of epileptic seizures induced in the Baboon Papio papio. During seizures the cerebral blood volume increases and there is simultaneously a decrease of blood volume in nasal and hepatic regions, and a transitory increase of blood volume in the forepaws. PMID:117933

  19. 21 CFR 862.1130 - Blood volume test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood volume test system. 862.1130 Section 862.1130 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  20. A reference frame for blood volume in children and adolescents

    Directory of Open Access Journals (Sweden)

    Donckerwolcke Raymond

    2006-02-01

    Full Text Available Abstract Background Our primary purpose was to determine the normal range and variability of blood volume (BV in healthy children, in order to provide reference values during childhood and adolescence. Our secondary aim was to correlate these vascular volumes to body size parameters and pubertal stages, in order to determine the best normalisation parameter. Methods Plasma volume (PV and red cell volume (RCV were measured and F-cell ratio was calculated in 77 children with idiopathic nephrotic syndrome in drug-free remission (mean age, 9.8 ± 4.6 y. BV was calculated as the sum of PV and RCV. Due to the dependence of these values on age, size and sex, all data were normalised for body size parameters. Results BV normalised for lean body mass (LBM did not differ significantly by sex (p Conclusion LBM was the anthropometric index most closely correlated to vascular fluid volumes, independent of age, gender and pubertal stage.

  1. Application of the (G'/G)-expansion method to nonlinear blood flow in large vessels

    International Nuclear Information System (INIS)

    As is widely known today, Navier-Stokes equations are used to describe blood flow in large vessels. In the past several decades, and even in very recent works, these equations have been reduced to Korteweg-de Vries (KdV), modified KdV or Boussinesq equations. In this paper, we avoid such simplifications and investigate the analytical traveling wave solutions of the one-dimensional generic Navier-Stokes equations, through the (G ' /G)-expansion method. These traveling wave solutions include hyperbolic functions, trigonometric functions and rational functions. Since some of them are not yet explored in the study of blood flow, we pay attention to hyperbolic function solutions and we show that the (G ' /G)-expansion method presents a wider applicability that allows us to bring out the widely known blood flow behaviors. The biological implications of the found solutions are discussed accordingly.

  2. Blunted autonomic response to volume expansion in formerly preeclamptic women with low plasma volume.

    NARCIS (Netherlands)

    Krabbendam, I.; Courtar, D.A.; Janssen, B.J.; Aardenburg, R.; Peeters, L.L.; Spaanderman, M.E.A.

    2009-01-01

    OBJECTIVE: We hypothesize that low plasma volume in normotensive formerly preeclamptic women reflects reduced venous storage capacity. To test this hypothesis, we compared circulatory and autonomic responses to acute volume loading between women with low and those with normal plasma volume. METHODS:

  3. The study of the volume expansion of aluminum during porous oxide formation at galvanostatic regime

    International Nuclear Information System (INIS)

    The volume expansion factor of porous alumina, formed by through anodizing of an Al foil of thickness 11.5 μm in the range of current densities of 4-35 mA cm-2 in oxalic and sulfuric acid at 18-24 deg. C has been studied. The microstructure of anodizing samples has been observed using scanning electron microscopy. The thickness of obtained porous alumina films was measured by a mechanical profilometer with a computer signal-processing. The volume expansion factor of porous alumina varied from 1.35 to 1.65. Linear dependences were obtained for the volume expansion factor of porous alumina versus the anodizing voltage and the ionic current-density logarithm versus the inverse volume expansion factor. Unlike oxide formation in sulfuric acid, these dependences have two subsequential rectilinear regions in oxalic acid. This peculiarity of the dependences in oxalic acid was explained by formation of a region of the immobile negative space charge in the barrier Al oxide layer and its influence on the ionic transport

  4. Does hyrax expansion therapy affect maxillary sinus volume? A cone-beam computed tomography report

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the initial effects of maxillary expansion therapy with Hyrax appliance and to evaluate the related changes in maxillary sinus volume. Thirty patients (20 females, 10 males; 13.8 years) requiring maxillary expansion therapy, as part of their comprehensive orthodontic treatment, were examined. Each patient had cone-beam computed tomography (CBCT) images taken before (T1) and after (T2) maxillary expansion therapy with a banded Hyrax appliance. Multiplanar slices were used to measure linear dimensions and palatal vault angle. Volumetric analysis was used to measure maxillary sinus volumes. Student t tests were used to compare the pre- and post-treatment measurements. Additionally, differences between two age groups were compared with Mann-Whitney U test. The level of significance was set at p=0.05. Comparison of pre-treatment to post-treatment variables revealed significant changes in the transverse dimension related to both maxillary skeletal and dental structures and palatal vault angle, resulting in a widened palatal vault (p<0.05). Hard palate showed no significant movement in the vertical and anteroposterior planes. Nasal cavity width increased on a mean value of 0.93 mm(SD=0.23, p<0.05). Maxillary sinus volume remained virtually stable. No significant age differences were observed in the sample. Hyrax expansion therapy did not have a significant impact on maxillary sinus volume.

  5. Does hyrax expansion therapy affect maxillary sinus volume? A cone-beam computed tomography report

    Energy Technology Data Exchange (ETDEWEB)

    Darsey, Drew M.; English, Jeryl D.; Ellis, Randy K.; Akyalcin, Sercan [School of Dentistry, University of Texas Health Science Center at Houston, Houston (United States); Kau, Chung H [School of Dentistry, University of Alabama at Birmingham, Birmingham (United States)

    2012-06-15

    The aim of this study was to investigate the initial effects of maxillary expansion therapy with Hyrax appliance and to evaluate the related changes in maxillary sinus volume. Thirty patients (20 females, 10 males; 13.8 years) requiring maxillary expansion therapy, as part of their comprehensive orthodontic treatment, were examined. Each patient had cone-beam computed tomography (CBCT) images taken before (T1) and after (T2) maxillary expansion therapy with a banded Hyrax appliance. Multiplanar slices were used to measure linear dimensions and palatal vault angle. Volumetric analysis was used to measure maxillary sinus volumes. Student t tests were used to compare the pre- and post-treatment measurements. Additionally, differences between two age groups were compared with Mann-Whitney U test. The level of significance was set at p=0.05. Comparison of pre-treatment to post-treatment variables revealed significant changes in the transverse dimension related to both maxillary skeletal and dental structures and palatal vault angle, resulting in a widened palatal vault (p<0.05). Hard palate showed no significant movement in the vertical and anteroposterior planes. Nasal cavity width increased on a mean value of 0.93 mm(SD=0.23, p<0.05). Maxillary sinus volume remained virtually stable. No significant age differences were observed in the sample. Hyrax expansion therapy did not have a significant impact on maxillary sinus volume.

  6. Changes in circulating blood volume following isoflurane or sevoflurane anesthesia.

    Science.gov (United States)

    Hamada, H; Takaori, M; Kimura, K; Fukui, A; Fujita, Y

    1993-07-01

    Changes of circulating blood volume (CB volume) measured by the dual indicator dilution method were observed in 33 chronically instrumented mongrel dogs following either alpha-chloralose-urethane (C group), additive isoflurane (I group) or sevoflurane anesthesia (S group). These anesthetic groups were each divided into two subgroups with regard to respiratory care, namely Cp, Ip and Sp for those with intermittent positive pressure ventilation (six animals per subgroups), and Cs, Is and Ss for those with spontaneous breathing (five animals per subgroups). The CB volume under positive pressure ventilation remained unchanged in the Ip and Sp groups at both 0.5 and 1.0 MAC, and in the Cp group. The CB volume remained essentially unchanged in the Cs and Is groups at both 0.5 or 1.0 MAC, but the plasma volume tended to increase slightly in the Is group at 1.0 MAC. In the Ss group under spontaneous breathing, however, the CB volume increased from 84.4 +/- 7.0 to 91.4 +/- 7.7 at 0.5 MAC, and to 91.4 +/- 10.2 ml.kg(-1) at 1.0 MAC (0.01 < P < 0.05). These increases were caused by an increase in the plasma volume. The above data suggests that a concomitant increase in the venous pressure associated with an increase in the intrathoracic pressure produced by positive pressure ventilation would attenuate changes in the CB volume during sevoflurane anesthesia. PMID:15278818

  7. Influence of Gravity on Blood Volume and Flow Distribution

    Science.gov (United States)

    Pendergast, D.; Olszowka, A.; Bednarczyk, E.; Shykoff, B.; Farhi, L.

    1999-01-01

    In our previous experiments during NASA Shuttle flights SLS 1 and 2 (9-15 days) and EUROMIR flights (30-90 days) we observed that pulmonary blood flow (cardiac output) was elevated initially, and surprisingly remained elevated for the duration of the flights. Stroke volume increased initially and then decreased, but was still above 1 Gz values. As venous return was constant, the changes in SV were secondary to modulation of heart rate. Mean blood pressure was at or slightly below 1 Gz levels in space, indicating a decrease in total peripheral resistance. It has been suggested that plasma volume is reduced in space, however cardiac output/venous return do not return to 1 Gz levels over the duration of flight. In spite of the increased cardiac output, central venous pressure was not elevated in space. These data suggest that there is a change in the basic relationship between cardiac output and central venous pressure, a persistent "hyperperfusion" and a re-distribution of blood flow and volume during space flight. Increased pulmonary blood flow has been reported to increase diffusing capacity in space, presumably due to the improved homogeneity of ventilation and perfusion. Other studies have suggested that ventilation may be independent of gravity, and perfusion may not be gravity- dependent. No data for the distribution of pulmonary blood volume were available for flight or simulated microgravity. Recent studies have suggested that the pulmonary vascular tree is influenced by sympathetic tone in a manner similar to that of the systemic system. This implies that the pulmonary circulation is dilated during microgravity and that the distribution of blood flow and volume may be influenced more by vascular control than by gravity. The cerebral circulation is influenced by sympathetic tone similarly to that of the systemic and pulmonary circulations; however its effects are modulated by cerebral autoregulation. Thus it is difficult to predict if cerebral perfusion is

  8. Portable, Constriction-Expansion Blood Plasma Separation and Polymerization-Based Malaria Detection.

    Science.gov (United States)

    Shatova, Tatyana A; Lathwal, Shefali; Engle, Marissa R; Sikes, Hadley D; Jensen, Klavs F

    2016-08-01

    A portable, microfluidic blood plasma separation device is presented featuring a constriction-expansion design, which produces 100.0% purity for undiluted blood at 9% yield. This level of purity represents an improvement of at least 1 order of magnitude with increased yield compared to that achieved previously using passive separation. The system features high flow rates, 5-30 μL/min plasma collection, with minimal clogging and biofouling. The simple, portable blood plasma separation design is hand-driven and can easily be incorporated with microfluidic or laboratory scale diagnostic assays. The separation system was applied to a paper-based diagnostic test for malaria that produced an amplified color change in the presence of Plasmodium falciparum histidine-rich protein 2 at a concentration well below clinical relevancy for undiluted whole blood. PMID:27366819

  9. The volume of fluid injected into the tissue expander and the tissue expansion

    Directory of Open Access Journals (Sweden)

    Mahmood Omranifard

    2014-01-01

    Full Text Available Background: Replacement of the lost tissue is the major concerns of the plastic surgeons. Expanded area should be coherent with the surrounding tissue. Tissue expansion technique is the reforming methods the skin tissue scarcities. Several methods for tissue expansion are available; including usage of silicon balloon and injecting fluid into the tissue expander. Materials and Methods: In a clinical trial study, 35 patients, with burn scars, in the face, skull and neck area were studied. We provided a tissue expander device with capacities of 125, 250 and 350cc. Fluid was injected inside the device, 3 consecutive weeks with 1-week interval. After 3 months the device was set out and the tissue expansion was measured using a transparent board and the results were analyzed. Multiple regression was done by SPSS 20 to analyze the data. Results: Regression model showed Skin expansion was positively correlated with the volume of the injected fluid. For each centimeter square of skin expansion, about 6-8 ml of fluid must be injected. Conclusion: Correction of skin defects resulting from burning scar is possible using tissue expanders. The tissue expansion is correlated with the amount of the injected fluid.

  10. Lack of anion effect on volume expansion natriuresis in the developing canine kidney.

    Science.gov (United States)

    Lorenz, J M; Kleinman, L I; Disney, T A

    1986-10-01

    The renal response to volume expansion with sodium chloride or sodium bicarbonate was studied in 15 newborn and 13 adult dogs. Proximal and distal nephron function were estimated using the technique of distal nephron blockade. Fractional sodium reabsorption was 99.0 +/- 0.3% in newborn and 96.6 +/- 0.06% in adult during the NaCl expansion (P less than 0.01) and 98.1 +/- 0.7% in the newborn and 93.2 +/- 0.7% in the adult during NaHCO3 expansion (P less than 0.001). With either anion the higher fractional sodium reabsorption in the newborn was due to reabsorption of a greater fraction of the load presented to the distal nephron segment. The percent of the distal sodium load that was reabsorbed was 98.0 +/- 0.6% in the newborn and 92.2 +/- 1.0% in the adult during NaCl expansion, and 96.1 +/- 1.3% in the newborn and 81.5 +/- 2.4% in the adult during NaHCO3 expansion. Differences in distal nephron chloride, potassium and bicarbonate reabsorption among the groups support the hypothesis that the enhanced distal sodium reabsorption in the newborn occurred largely in the ascending loop of Henle with NaCl expansion, while it occurred in the late distal and cortical collecting tubules with NaHCO3 expansion. There was no difference between the natriuretic responses to NaCl or NaHCO3 in the newborn (P greater than 0.20); however, the natriuretic response to NaCl was less than that to NaHCO3 in the adult (P less than 0.001). This suggests that the bulk of the sodium that escaped reabsorption in Henle's loop during NaHCO3 expansion was reabsorbed in the late distal tubule in the newborn, but not in the adult. PMID:3025284

  11. Accuracy of a new bedside method for estimation of circulating blood volume

    DEFF Research Database (Denmark)

    Christensen, P; Waever Rasmussen, J; Winther Henneberg, S

    1993-01-01

    To evaluate the accuracy of a modification of the carbon monoxide method of estimating the circulating blood volume.......To evaluate the accuracy of a modification of the carbon monoxide method of estimating the circulating blood volume....

  12. A novel monoclonal antibody of human stem cell factor inhibits umbilical cord blood stem cell ex vivo expansion

    Directory of Open Access Journals (Sweden)

    Fan Jie

    2012-12-01

    Full Text Available Abstract Stem cell factor (SCF activates hematopoietic stem cell (HSC self-renewal and is being used to stimulate the ex vivo expansion of HSCs. The mechanism by which SCF supports expansion of HSCs remains poorly understood. In cord blood ex vivo expansion assays, a newly produced anti-SCF monoclonal antibody (clone 23C8 was found to significantly inhibit the expansion of CD34+ cells. This antibody appears to bind directly to a part of SCF that is critical for biological activity toward expansion of CD34+ cells, which is located in the first 104 amino acids from the NH2-terminus.

  13. A single-centre study of vasovagal reaction in blood donors: Influence of age, sex, donation status, weight, total blood volume and volume of blood collected

    Directory of Open Access Journals (Sweden)

    Joseph Philip

    2014-01-01

    Full Text Available Context: Vasovagal reactions (VVRs in blood donors. Aim: To find an association of age, sex, donation status, weight, total blood volume and volume of blood collected with occurrence of immediate VVR. Settings and Design: Retrospective single-centre study. Materials and Methods: The study was conducted from March 2000 to November 2010 at a tertiary care blood transfusion centre. All VVRs with or without syncope occurring during or at the end of donation were noted. Statistical Analysis Used: For qualitative association, c 2 -test was used. Unpaired ′t′ test was used for assessing difference between two groups with respect to VVR status. Simultaneous impact of all risk factors was assessed using multivariate logistic regression analysis. The data entry software SPSS (version 17.0 was used for statistical analysis. A P-value <0.05 was considered statistically significant. Results: Overall 1085 VVRs were reported in relation to 88,201 donations, resulting in an overall VVR rate of 1.23%, that is, an incidence of 1 in every 81 donations. Donors with low blood volume, first-time donors, with low weight and female donors had higher absolute donation VVR rates than other donors. Conclusions: Donation-related vasovagal syncopal reactions are a multifactorial process determined largely by weight, age, first-time donor status and total blood volume. Our study reinforces the fact that blood donation is a very safe procedure, which could be made even more event-free by following certain friendly, reassuring practices and by ensuring strict pre-donation screening procedures.

  14. RELATIVE BLOOD VOLUME: THE MEANS OF INTRADIALYSIS HYPOTENSION PREVENTION

    Directory of Open Access Journals (Sweden)

    V. A. Terehov

    2010-06-01

    Full Text Available Intravascular volume preservation is the first choice measure for the prevention of intradialysis hypotension. At present there are devices that allow continuous monitoring of relative blood volume (RBV changes during haemodialysis (HD. The aim of this research was to investigate (i the regularity of RBV curve during haemo- dialysis and (ii the efficacy of some measures for intravascular volume preservation. In patients with hyperhydration RBV curves were monotone; in all cases relation RBV/ ultrafiltration volume (UF did not exceed 2,5%/L. In stable patients the RBV curve was immutable in the course of years. Patients with high RBV/UF ratio (>6%/L formed a high risk group. In these patients stability of RBV was more im- portant and more useful. Isolated UF did not decrease RBV drop, as well as haemodiafiltration online. Albumin administration allows to decrease RBV/UF ratio. After bolus of hypertonic dextrose solution RBV increased for about half of hour. In patients with acute renal injury RBV monitoring was far from reliability in many cases. 

  15. Venous flow velocity, venous volume and arterial blood flow

    International Nuclear Information System (INIS)

    The relationship of arterial blood flow and venous volume to venous flow velocity was studied in normal subjects. The effects of current modes of treatment in venous thrombosis and of a vasodilator drug on venous flow velocity were also investigated. Total calf flow and venous volume were measured by venous occlusion plethysmography while venous flow axial velocity was determined by the transit time of 131I albumin from calf to inguinal region. Local intravenous epinephrine administration induced venoconstriction and increased venous flow velocity. Intra-arterial isoproterenol and angiotensin increased and decreased arterial flow, respectively, with no change in venous flow velocity or volume, but local heat increased arterial flow and venous flow velocity with no change in venous volume. Local cold, despite venoconstriction, decreased venous flow velocity accompanied by decreased arterial flow. Intravenous heparin did not affect venous flow velocity. Intravenous but not oral nylidrin increased venous flow velocity. Therefore venous flow velocity can be significantly increased by venoconstriction, by large increases in arterial flow (local heat), and by a parenteral vasodilator drug. These experiments indicate that there is a basis for applying heat but not cold in the prevention and treatment of venous thrombosis

  16. Volume weighting the measure of the universe from classical slow-roll expansion

    Science.gov (United States)

    Sloan, David; Silk, Joseph

    2016-05-01

    One of the most frustrating issues in early universe cosmology centers on how to reconcile the vast choice of universes in string theory and in its most plausible high energy sibling, eternal inflation, which jointly generate the string landscape with the fine-tuned and hence relatively small number of universes that have undergone a large expansion and can accommodate observers and, in particular, galaxies. We show that such observations are highly favored for any system whereby physical parameters are distributed at a high energy scale, due to the conservation of the Liouville measure and the gauge nature of volume, asymptotically approaching a period of large isotropic expansion characterized by w =-1 . Our interpretation predicts that all observational probes for deviations from w =-1 in the foreseeable future are doomed to failure. The purpose of this paper is not to introduce a new measure for the multiverse, but rather to show how what is perhaps the most natural and well-known measure, volume weighting, arises as a consequence of the conservation of the Liouville measure on phase space during the classical slow-roll expansion.

  17. Clonal T cell expansion induced by interleukin 2 therapy in blood and tumors.

    OpenAIRE

    Kumar, A; Farace, F.; Gaudin, C; Triebel, F

    1996-01-01

    In a phase I clinical trial on the effects of preoperative adjuvant IL-2 therapy given to patients undergoing hepatic resection of colorectal adenocarcinoma metastases, we monitored the putative induction of T cell clonal expansion in both tissues and blood. The presence of T cell clonotypes was analyzed with a PCR-based method that determines V-D-J junction size patterns in T cell receptor (TCR) V beta subfamilies in samples before and after a 5-d IL-2 infusion. This high resolution method a...

  18. Resistance exercise with different volumes: blood pressure response and forearm blood flow in the hypertensive elderly

    OpenAIRE

    Brito AF; Oliveira CV; Brasileiro-Santos MS; Santos AC

    2014-01-01

    Aline de Freitas Brito,1 Caio Victor Coutinho de Oliveira,2 Maria do Socorro Brasileiro-Santos,1 Amilton da Cruz Santos1 1Physical Education Department, 2Research Laboratory for Physical Training Applied to Performance and Health, Federal University of Paraíba, João Pessoa, Brazil Background: The purpose of this study was to evaluate the effect of two sessions of resistance exercise with different volumes on post-exercise hypotension, forearm blood flow, and forearm vascular re...

  19. Hearing Outcomes After Stereotactic Radiosurgery for Unilateral Intracanalicular Vestibular Schwannomas: Implication of Transient Volume Expansion

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dong Gyu, E-mail: gknife@plaza.snu.ac.kr [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Jung Ho [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Jeong-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Chae-Yong [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Paek, Sun Ha; Jung, Hee-Won [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2013-01-01

    Purpose: We evaluated the prognostic factors for hearing outcomes after stereotactic radiosurgery (SRS) for unilateral sporadic intracanalicular vestibular schwannomas (IC-VSs) as a clinical homogeneous group of VSs. Methods and Materials: Sixty consecutive patients with unilateral sporadic IC-VSs, defined as tumors in the internal acoustic canal, and serviceable hearing (Gardner-Roberson grade 1 or 2) were treated with SRS as an initial treatment. The mean tumor volume was 0.34 {+-} 0.03 cm{sup 3} (range, 0.03-1.00 cm{sup 3}), and the mean marginal dose was 12.2 {+-} 0.1 Gy (range, 11.5-13.0 Gy). The median follow-up duration was 62 months (range, 36-141 months). Results: The actuarial rates of serviceable hearing preservation were 70%, 63%, and 55% at 1, 2, and 5 years after SRS, respectively. In multivariate analysis, transient volume expansion of {>=}20% from initial tumor size was a statistically significant risk factor for loss of serviceable hearing and hearing deterioration (increase of pure tone average {>=}20 dB) (odds ratio = 7.638; 95% confidence interval, 2.317-25.181; P=.001 and odds ratio = 3.507; 95% confidence interval, 1.228-10.018; P=.019, respectively). The cochlear radiation dose did not reach statistical significance. Conclusions: Transient volume expansion after SRS for VSs seems to be correlated with hearing deterioration when defined properly in a clinically homogeneous group of patients.

  20. Current Injection Provokes Rapid Expansion of the Guard Cell Cytosolic Volume and Triggers Ca(2+) Signals.

    Science.gov (United States)

    Voss, Lena J; Hedrich, Rainer; Roelfsema, M Rob G

    2016-03-01

    High-resolution microscopy opens the door for detailed single-cell studies with fluorescent reporter dyes and proteins. We used a confocal spinning disc microscope to monitor fluorescent dyes and the fluorescent protein Venus in tobacco and Arabidopsis guard cells. Multi-barreled microelectrodes were used to inject dyes and apply voltage pulses, which provoke transient rises in the cytosolic Ca(2+) level. Voltage pulses also caused changes in the distribution of Lucifer Yellow and Venus, which pointed to a reversible increase of guard cell cytosolic volume. The dynamic cytosolic volume changes turned out to be provoked by current injection of ions. A reduction of the clamp current, by blocking K(+) uptake channels with Cs(+), strongly suppressed the cytosolic volume changes. Cs(+) not only inhibited the expansion of the cytosol, but also inhibited hyperpolarization-induced elevations of the cytosolic Ca(2+) concentration. A complete loss of voltage-induced Ca(2+) signals occurred when Ca(2+)-permeable plasma membrane channels were simultaneously blocked with La(3+). This shows that two mechanisms cause hyperpolarization-induced elevation of the cytosolic Ca(2+)-concentration: (i) activation of voltage-dependent Ca(2+)-permeable channels, (ii) osmotically induced expansion of the cytosol, which leads to a release of Ca(2+) from intracellular stores. PMID:26902185

  1. Impact of volume expansion on the efficacy and pharmacokinetics of liposome bupivacaine

    Directory of Open Access Journals (Sweden)

    Hadzic A

    2015-12-01

    Full Text Available Admir Hadzic,1,2 John A Abikhaled,3 William J Harmon4 1Department of Anesthesiology, The New York School of Regional Anesthesia (NYSORA, New York, NY, USA; 2Department of Anesthesiology, Ziekenhouse Oost Limburgh, Genk, Belgium; 3Austin Surgeons, Austin, TX, 4Urology San Antonio, San Antonio, TX, USA Abstract: Liposome bupivacaine is a prolonged-release liposomal formulation of bupivacaine indicated for single-dose infiltration into the surgical site to produce postsurgical analgesia of longer duration than traditional local anesthetics. This review summarizes the available data on how volume expansion may impact the analgesic efficacy of liposome bupivacaine. The Phase II and III clinical studies that involved surgical site administration of liposome bupivacaine at various concentrations in different surgical settings revealed no apparent concentration–efficacy relationship. A single-center, prospective study comparing the efficacy of transversus abdominis plane infiltration with liposome bupivacaine administered in a lower (266 mg/40 mL vs a higher (266 mg/20 mL dose concentration in subjects undergoing robotic-assisted laparoscopic prostatectomy also reported similar postsurgical pain intensity scores and opioid usage in both treatment groups. The pharmacokinetic profile of liposome bupivacaine following subcutaneous injections in rats was unaltered by differences in drug concentration, dose, or injection volume within the ranges tested. Volume expansion of liposome bupivacaine to a total volume of 300 mL or less does not appear to impact its clinical efficacy or pharmacokinetic profile, thus allowing flexibility to administer the formulation across a wide range of diluent volumes. Keywords: pain, analgesia, liposome bupivacaine, dose, concentration, dilution 

  2. Clonal T cell expansion induced by interleukin 2 therapy in blood and tumors.

    Science.gov (United States)

    Kumar, A; Farace, F; Gaudin, C; Triebel, F

    1996-01-01

    In a phase I clinical trial on the effects of preoperative adjuvant IL-2 therapy given to patients undergoing hepatic resection of colorectal adenocarcinoma metastases, we monitored the putative induction of T cell clonal expansion in both tissues and blood. The presence of T cell clonotypes was analyzed with a PCR-based method that determines V-D-J junction size patterns in T cell receptor (TCR) V beta subfamilies in samples before and after a 5-d IL-2 infusion. This high resolution method analyzing CDR3 sizes of TCR transcripts was used in conjunction with FACS analysis of the corresponding T cell subpopulations with TCR V beta-specific mAb. At time of surgery (day 8 after starting IL-2), we found in the three patients analyzed with V beta-C beta primers multiple dominant T cell clonotypes in the tumor and peritumoral tissues which had probably expanded as a result of therapy. In three control patients not treated with IL-2, multiple oligoclonal patterns were not observed with this set of primers. In the fourth control patient a unique V beta 21-C beta CDR3 pattern which corresponds to two dominant clonotypes was found in the tumor. The same dominant clonotypes identified in the tumor after IL-2 were also detectable in the blood and comparison of the profiles obtained before and after IL-2 therapy indicates that they were induced by IL-2. The relative expansion of the corresponding T cell subpopulations was maintained for varying periods of time after surgery (4-7 d and almost 2 yr in one case). Together, these results indicate that IL-2 induces marked expansion of several T cell clones. Systemic IL-2 administration may represent, either alone or as a vaccine adjuvant, an appropriate way of boosting antigen-specific immune responses. PMID:8636433

  3. Resistance exercise with different volumes: blood pressure response and forearm blood flow in the hypertensive elderly

    Directory of Open Access Journals (Sweden)

    Brito AF

    2014-12-01

    Full Text Available Aline de Freitas Brito,1 Caio Victor Coutinho de Oliveira,2 Maria do Socorro Brasileiro-Santos,1 Amilton da Cruz Santos1 1Physical Education Department, 2Research Laboratory for Physical Training Applied to Performance and Health, Federal University of Paraíba, João Pessoa, Brazil Background: The purpose of this study was to evaluate the effect of two sessions of resistance exercise with different volumes on post-exercise hypotension, forearm blood flow, and forearm vascular resistance in hypertensive elderly subjects.Methods: The study was conducted with ten hypertensive elderly (65±3 years, 28.7±3 kg/m2 subjected to three experimental sessions, ie, a control session, exercise with a set (S1, and exercise with three sets (S3. For each session, the subjects were evaluated before and after intervention. In the pre-intervention period, blood pressure, forearm blood flow, and forearm vascular resistance were measured after 10 minutes of rest in the supine position. Thereafter, the subjects were taken to the gym to perform their exercise sessions or remained at rest during the same time period. Both S1 and S3 comprised a set of ten repetitions of ten exercises, with an interval of 90 seconds between exercises. Subsequently, the measurements were again performed at 10, 30, 50, 70, and 90 minutes of recovery (post-intervention in the supine position.Results: Post-exercise hypotension was greater in S3 than in S1 (systolic blood pressure, −26.5±4.2 mmHg versus −17.9±4.7 mmHg; diastolic blood pressure, −13.8±4.9 mmHg versus −7.7±5 mmHg, P<0.05. Similarly, forearm blood flow and forearm vascular resistance changed significantly in both sessions with an increase and decrease, respectively, that was more evident in S3 than in S1 (P<0.05.Conclusion: Resistance exercises with higher volume were more effective in causing post-exercise hypotension, being accompanied by an increase in forearm blood flow and a reduction of forearm vascular

  4. Colloid volume loading does not mitigate decreases in central blood volume during simulated hemorrhage while heat stressed

    DEFF Research Database (Denmark)

    Crandall, Craig G; Wilson, Thad E; Marving, Jens;

    2012-01-01

    attenuates the reduction in regional blood volumes during a simulated hemorrhagic challenge imposed via lower-body negative pressure (LBNP). Seven subjects underwent 30 mmHg LBNP while normothermic, during passive heat stress (increased internal temperature ~1°C), and while continuing to be heated after......±3%; spleen: 72±5%, all P0.05 relative to heat stress alone). These data suggest that blood volume loading during passive heat stress (via 11 ml/kg of a colloid solution) normalizes regional blood volumes in the torso, but does not mitigate the reduction in central blood volume during a simulated hemorrhagic......Heat stress results in profound reductions in the capacity to withstand a simulated hemorrhagic challenge; however, this capacity is normalized if the individual is volume loaded prior to the challenge. The present study tested the hypothesis that volume loading during passive heat stress...

  5. Glue embolization of the giant aneurysm by reducing thrombosis-induced volume expansion effect

    Energy Technology Data Exchange (ETDEWEB)

    Yeom, Yoo Kyung; Suh, Dae Chul [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2015-04-15

    A giant aneurysm due to a large intra-aneurysmal volume can be complicated by a delayed massive volume expansion caused by thrombus formation. To prevent such a severe mass effect, we obliterated the aneurysmal lumen by gluing and prevented further development of thrombosis. A 52-year-old female with a giant aneurysm at the cavernous segment of the internal carotid artery presented with tinnitus and intermittent diplopia. After confirming with a negative occlusion test, the right internal carotid artery was trapped by coiling and with further obliteration of the aneurysmal lumen by gluing. She developed a mild diplopia after the procedure and recovered without any deficit. The magnetic resonance angiography showed a stable occlusion of the aneurysm and good collateral filling of the cerebral vessel 15 months later.

  6. Increased digitalis-like activity in human cerebrospinal fluid after expansion of the extracellular fluid volume

    International Nuclear Information System (INIS)

    The present study was designed to determine whether acute expansion of the extracellular fluid volume influenced the digitalis-like activity of human cerebrospinal fluid (CSF), previously described. Human CSF samples, drawn before and 30 minutes after the intravenous infusion of 1 liter of either saline or glucose solutions, were assayed for digitalis-like activity by inhibition of either the 86Rb+ uptake into human erythrocytes or by the activity of a purified Na+-K+ ATPase. The CSF inhibitory activity on both systems significantly increased after the infusion of sodium solutions but did not change after the infusion of glucose. These results indicate that the digitalis-like factor of human CSF might be involved in the regulation of the extracellular fluid volume and electrolyte content and thereby in some of the physiological responses to sodium loading. 31 references, 2 figures, 1 table

  7. FINITE VOLUME METHOD FOR SIMULATION OF VISCOELASTIC FLOW THROUGH A EXPANSION CHANNEL

    Institute of Scientific and Technical Information of China (English)

    FU Chun-quan; JIANG Hai-mei; YIN Hong-jun; SU Yu-chi; ZENG Ye-ming

    2009-01-01

    A finite volume method for the numerical solution of viscoelastic flows is given. The flow of a differential Upper-Convected Maxwell (UCM) fluid through an abrupt expansion has been chosen as a prototype example. The conservation and constitutive equations are solved using the Finite Volume Method (FVM) in a staggered grid with an upwind scheme for the viscoelastic stresses and a hybrid scheme for the velocities. An enhanced-in-speed pressure-correction algorithm is used and a method for handling the source term in the momentum equations is employed. Improved accuracy is achieved by a special discretization of the boundary conditions. Stable solutions are obtained for higher Weissenberg number (We), further extending the range of simulations with the FVM. Numerical results show the viscoelasticity of polymer solutions is the main factor influencing the sweep efficiency.

  8. Isothermal Volume Expansion of a TATB-Based Composite and the Effect on Compressive Strength

    Science.gov (United States)

    Thompson, Darla; Schwarz, Ricardo; Deluca, Racci

    2015-06-01

    It has long been known that compacted composites containing TATB crystals undergo ``ratchet growth,'' an irreversible volume expansion upon thermal cycling. A mechanism has not been established but is believed to arise from the highly-anisotropic CTE of TATB crystals and the interactions caused by compaction. Because explosive performance depends fundamentally on bulk density, the details of this phenomenon are important to understand. PBX 9502 is a plastic bonded explosive containing 95 wt% TATB crystals. We have used a TA Instruments thermal mechanical analyzer (TMA) to monitor uniaxial length changes of PBX 9502 specimens as a function of temperature and thermal cycling. Previous ``ratchet growth'' work has focused on irreversible expansion as a function of temperature range and number of thermal cycles (1). In the work reported here, we demonstrate that irreversible growth also occurs during extended isothermal conditions and especially at elevated temperatures. We explore PBX 9502 irreversible expansion as a function of time and temperature, in the form of thermal ramps and holds. Post-test specimens are then subjected to quasi-static compression testing to determine whether the mechanical properties correlate with the final bulk density, or depend in a more complex way on the detailed thermal history of the specimen.

  9. Oxygenation and Blood Volume Periodic Waveforms in the Brain

    CERN Document Server

    Gersten, Alexander; Raz, Amir

    2011-01-01

    Results of an experiment are presented whose aim is to explore the relationship between respiration and cerebral oxygenation. Measurements of end tidal CO2 (EtCO2) were taken simultaneously with cerebral oxygen saturation (rSO2) using the INVOS Cerebral Oximeter of Somanetics. Due to the device limitations we could explore only subjects who could perform with a breathing rate of around 2/min or less. Six subjects were used who were experienced in yoga breathing techniques. They performed an identical periodic breathing exercise including periodicity of about 2/min. The results of all six subjects clearly show a periodic change of cerebral oxygenation with the same period as the breathing exercises. Similar periodic changes in blood volume index were observed as well.

  10. Analysis of volume expansion data for periclase, lime, corundum and spinel at high temperatures

    Indian Academy of Sciences (India)

    B P Singh; H Chandra; R Shyam; A Singh

    2012-08-01

    We have presented an analysis of the volume expansion data for periclase (MgO), lime (CaO), corundum (Al2O3) and spinel (MgAl2O4) determined experimentally by Fiquet et al (1999) from 300K up to 3000K. The thermal equation of state due to Suzuki et al (1979) and Shanker et al (1997) are used to study the relationships between thermal pressure and volume expansion for the entire range of temperatures starting from room temperature up to the melting temperatures of the solids under study. Comparison of the results obtained in the present study with the corresponding experimental data reveal that the thermal pressure changes with temperature almost linearly up to quite high temperatures. At extremely high temperatures close to the melting temperatures thermal pressure deviates significantly from linearity. This prediction is consistent with other recent investigations. A quantitative analysis based on the theory of anharmonic effects has been presented to account for the nonlinear variation of the thermal pressure at high temperatures.

  11. Pulmonary blood volume (PRV) in rats with chronic mountain sickness

    International Nuclear Information System (INIS)

    Upon chronic exposure to severe hypoxia, Hilltop (H) strain of Sprague-Dawley rats develops excessive polycythemia, severe hypervolemia and marked elevation in pulmonary arterial pressure (PAP), whereas Madison (M) strain develops only moderate responses. Hypervolemia is expected to increase the PBV which might contribute to the development of severe pulmonary hypertension. Two groups of 6 animals each of the H and M strains were exposed to sea level (SL) and a simulated altitude of 18,000 ft for 14 days. At the end of exposure each animal was measured for RBC volume (RBCV), total blood volume (TBV), PBV and PAP under normoxia for control and under hypoxia (10% O2) for the hypoxic groups. RBCV was determined by 51Cr-RBC dilution and PBV was trapped by tightening an implanted loose ligature around the ascending aorta and PA. There were not strain differences in all parameters studied at SL. RBCV, TBV and PAP increased with hypoxia in both strains but significantly more so in H than M. PBV per g lung WT decreased in both strains despite elevated TBV and PAP, but more so in M than H. There were good correlations between the PBV and TBV, and between PAP and PBV in the hypoxic H and M rats. The data suggest that chronic hypoxia reduced the distensibility and perhaps the vascular capacity of the lungs such that small relative increase in PBV could significantly contribute to the rise in PAP

  12. [Effects of volume and rate of blood loss on indicators of auto-hemodilution].

    Science.gov (United States)

    Koval'skaia, K S; Baluev, E P; Krivitskiĭ, N M

    1991-06-01

    The results of synchronous monitoring of blood impedance versus body impedance in dog experiments showed that the speed of physiological hemodilution related to blood loss up to 30 ml/kg is poorly dependent on the rate of blood loss (0.4-1.0 ml/kg/min) and averages 0.186 +/- 0.02 ml/min/kg. Termination of blood loss is followed by marked reduction in the rate of auto-hemodilution. In bloodletting the studies revealed a linear dependence between the volume of blood loss up to 30 ml/kg and tissue fluid volume entering the blood stream. In blood loss intestinal absorption of fluid does not block the fluid introduction from the interstice. When associated, both these flows increase volume of fluid filling vascular bed and promote stable recovery of the baseline circulating blood volume. PMID:1893173

  13. 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

  14. In vitro expansion of Lin+ and Lin− mononuclear cells from human peripheral blood

    International Nuclear Information System (INIS)

    Haematopoietic stem cells (HSCs) are used in the therapy of blood disorders due to the ability of these cells to reconstitute haematopoietic lineage cells when transplanted into myeloablative recipients. However, substantial number of cells is required in order for the reconstitution to take place. Since HSCs present in low frequency, larger number of donor is required to accommodate the demand of transplantable HSCs. Therefore, in vitro expansion of HSCs will have profound impact on clinical purposes. The aim of this study was to expand lineage negative (Lin−) stem cells from human peripheral blood. Total peripheral blood mononuclear cells (PBMNCs) were fractionated from human blood by density gradient centrifugation. Subsequently, PBMNCs were subjected to magnetic assisted cell sorter (MACS) which depletes lineage positive (Lin+) mononuclear cells expressing lineage positive markers such as CD2, CD3, CD11b, CD14, CD15, CD16, CD19, CD56, CD123, and CD235a to obtained Lin− cell population. The ability of Lin+ and Lin− to survive in vitro was explored by culturing both cell populations in complete medium consisting of Alpha-Minimal Essential Medium (AMEM) +10% (v/v) Newborn Calf Serum (NBCS)+ 2% (v/v) pen/strep. In another experiment, Lin+ and Lin− were cultured with complete medium supplemented with 10ng/mL of the following growth factors: stem cell factor (SCF), interleukin (IL)-3, granulocyte-macrophage colony stimulating factor (GM-CSF), 2IU/mL of Erythropoietin (Epo) and 20ng/mL of IL-6. Three samples were monitored in static culture for 22 days. The expansion potential was assessed by the number of total viable cells, counted by trypan blue exclusion assay. It was found that Lin+ mononuclear cells were not able to survive either in normal proliferation medium or proliferation medium supplemented with cytokines. Similarly, Lin− stem cells were not able to survive in proliferation medium however, addition of cytokines into the proliferation medium

  15. Determination of the total blood volume of the rat using chromium 51 (1962)

    International Nuclear Information System (INIS)

    In various experiments it is important that the rat's blood volume should be known and it is essential that it could be worked out by simply weighing the animal. Therefore authors decided to work out systematically with chromium 51 blood volume for rats with different weights. Results have shown that blood volume for 100 g is 5.55 ml and that it does not seen to vary with the weight of animals. (authors)

  16. The High Yield Expansion and Megakaryocytic Differentiation of Human Umbilical Cord Blood CD133+ Cells

    Directory of Open Access Journals (Sweden)

    Mahin Nikougoftar Zarif

    2011-01-01

    Full Text Available Objective: Despite of many benefits, umbilical cord blood (UCB hematopoietic stem cell(HSC transplantation is associated with low number of stem cells and slow engraftment;in particular of platelets. So, expanded HSCs and co-transfusion of megakaryocyte (MKprogenitor cells can shorten this period. In this study, we evaluated the cytokine conditionsfor maximum expansion and MK differentiation of CD133+ HSCs.Materials and Methods: In this experimental study, The CD133+ cells were separatedfrom three cord blood samples by magnetic activated cell sorting (MACS method, expandedin different cytokine combinations for a week and differentiated in thrombopoietin(TPO for the second week. Differentiation was followed by the flow cytometry detectionof CD41 and CD61 surface markers. Colony forming unit (CFU assay and DNA analysiswere done for colonogenic capacity and ploidy assay.Results: CD133+ cells showed maximum expansion in the stem span medium with stemcell factor (SCF + FMS-like tyrosine kinase 3-ligand (Flt3-L + TPO but the maximum differentiationwas seen when CD133+ cells were expanded in stem span medium with SCF+ Interleukin 3 (IL-3 + TPO for the first and in TPO for the second week. Colony FormingUnit-MK (CFU-MK was formed in three sizes of colonies in the mega-cult medium. In theDNA analysis; 25.2 ± 6.7% of the cells had more than 2n DNA mass.Conclusion: Distinct differences in the MK progenitor cell count were observed when thecells were cultured in stem span medium with TPO, SCF, IL-3 and then the TPO in thesecond week. Such strategy could be applied for optimization of CD133+ cells expansionfollowed by MK differentiation.

  17. Cord Blood-Derived Hematopoietic Stem/Progenitor Cells: Current Challenges in Engraftment, Infection, and Ex Vivo Expansion

    Directory of Open Access Journals (Sweden)

    Katsuhiro Kita

    2011-01-01

    Full Text Available Umbilical cord blood has served as an alternative to bone marrow for hematopoietic transplantation since the late 1980s. Numerous clinical studies have proven the efficacy of umbilical cord blood. Moreover, the possible immaturity of cells in umbilical cord blood gives more options to recipients with HLA mismatch and allows for the use of umbilical cord blood from unrelated donors. However, morbidity and mortality rates associated with hematopoietic malignancies still remain relatively high, even after cord blood transplantation. Infections and relapse are the major causes of death after cord blood transplantation in patients with hematopoietic diseases. Recently, new strategies have been introduced to improve these major problems. Establishing better protocols for simple isolation of primitive cells and ex vivo expansion will also be very important. In this short review, we discuss several recent promising findings related to the technical improvement of cord blood transplantation.

  18. Cord Blood-Derived Hematopoietic Stem/Progenitor Cells: Current Challenges in Engraftment, Infection, and Ex Vivo Expansion

    Science.gov (United States)

    Kita, Katsuhiro; Lee, Jong O.; Finnerty, Celeste C.; Herndon, David N.

    2011-01-01

    Umbilical cord blood has served as an alternative to bone marrow for hematopoietic transplantation since the late 1980s. Numerous clinical studies have proven the efficacy of umbilical cord blood. Moreover, the possible immaturity of cells in umbilical cord blood gives more options to recipients with HLA mismatch and allows for the use of umbilical cord blood from unrelated donors. However, morbidity and mortality rates associated with hematopoietic malignancies still remain relatively high, even after cord blood transplantation. Infections and relapse are the major causes of death after cord blood transplantation in patients with hematopoietic diseases. Recently, new strategies have been introduced to improve these major problems. Establishing better protocols for simple isolation of primitive cells and ex vivo expansion will also be very important. In this short review, we discuss several recent promising findings related to the technical improvement of cord blood transplantation. PMID:21603139

  19. Do distribution volumes and clearances relate to tissue volumes and blood flows? A computer simulation

    Directory of Open Access Journals (Sweden)

    Lemmens Hendrikus JM

    2006-06-01

    Full Text Available Abstract Background Kinetics of inhaled agents are often described by physiological models. However, many pharmacokinetic concepts, such as context-sensitive half-times, have been developed for drugs described by classical compartmental models. We derived classical compartmental models that describe the course of the alveolar concentrations (FA generated by the physiological uptake and distribution models used by the Gas Man® program, and describe how distribution volumes and clearances relate to tissue volumes and blood flows. Methods Gas Man® was used to generate FA vs. time curves during the wash-in and wash-out period of 115 min each with a high fresh gas flow (8 L.min-1, a constant alveolar minute ventilation (4 L.min-1, and a constant inspired concentration (FI of halothane (0.75%, isoflurane (1.15%, sevoflurane (2%, or desflurane (6%. With each of these FI, simulations were ran for a 70 kg patient with 5 different cardiac outputs (CO (2, 3, 5, 8 and 10 L.min-1 and for 5 patients with different weights (40, 55, 70, 85, and 100 kg but the same CO (5 L.min-1. Two and three compartmental models were fitted to FA of the individual 9 runs using NONMEM. After testing for parsimony, goodness of fit was evaluated using median prediction error (MDPE and median absolute prediction error (MDAPE. The model was tested prospectively for a virtual 62 kg patient with a cardiac output of 4.5 L.min-1 for three different durations (wash-in and wash-out period of 10, 60, and 180 min each with an FI of 1.5% halothane, 1.5% isoflurane, sevoflurane 4%, or desflurane 12%. Results A three-compartment model fitted the data best (MDPE = 0% and MDAPE ≤ 0.074% and performed equally well when tested prospectively (MDPE ≤ 0.51% and MDAPE ≤ 1.51%. The relationship between CO and body weight and the distribution volumes and clearances is complex. Conclusion The kinetics of anesthetic gases can be adequately described e by a mammilary compartmental model. Therefore

  20. Molar volume, thermal expansivity and isothermal compressibility of trans-decahydronaphthalene up to 200MPa and 446K

    Institute of Scientific and Technical Information of China (English)

    Zhu Hu-Gang; Liu Zhi-Hua; Tian Yi-Ling; Xue Yuan; Yin Liang

    2005-01-01

    The molar volume isotherms of trans-decahydronaphthalene (C10H18) between 293 and 446 K and at pressures from 10 to 200 MPa have been determined. A modified Tait equation of state is used to fit each experimental molar volume isotherm with a maximum average deviation of 0.029%. The thermal expansivity (cubic expansion coefficient) α and isothermal compressibility κ were determined by fitting the slopes of the isobaric curves and isotherms, respectively.The coefficients in the equation Vm = C1 + C2T + C3T2 - C4p - C5pT have been fitted with an average deviation of 1.03%.

  1. Decreased myocardial blood volume is a cause of reduced myocardial blood flow reserve in hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    The purposes of this study are to know whether myocardial blood volume (MBV) is decreased in the left ventricular myocardium of patients with hypertrophic cardiomyopathy (HCM), and to elucidate which of the decreased MBV or of the reduced rate (mean transit rate of the blood) of myocardial blood flow (MBF), is the cause of the reduced MBF at reactive hyperemia. Subjects were 22 non-obstructive HCM patients (M16/F6, mean age 54 y) exhibiting asymmetric ventricular septum hypertrophy in echocardiography (EC) and 9 male age-matched healthy volunteers. The machine used for EC was Sonos 5500 (Philips Medical Systems) and myocardial contrast EC (MCE) was conducted also with the machine and S3 probe with 1.3/2.6 MHz to get harmonic power Doppler image. The contrast medium was Levovist (Schering AG), which was intravenously infused continuously during EC, and adenosine 5'-triphosphate (ATP) was similarly given to induce the reactive hyperemia. MCE images were processed by the software VoluMap-445 (YD LTD) for calculating MBV (%; mL/100 mL). For obtaining MBF (mL/min/g), positron emission tomography (PET) was done with the machine Siemens/CTI ECAT EXACT HR+Scanner, using 15O-water prepared in Sumitomo cyclotron CYPRIS-HM18, in 13 patients and all volunteers. The mean transit rate was calculated by (MBF/MBV) x 1.67/sec. It was found that MBV was decreased relatedly with the local wall thickness of HCM patients' left ventricular myocardium and MBF was reduced dependently on the decreased MBV at the reactive hyperemia. (R.T.)

  2. The effect of an acute increase in central blood volume on the response of cerebral blood flow to acute hypotension.

    Science.gov (United States)

    Ogoh, Shigehiko; Hirasawa, Ai; Sugawara, Jun; Nakahara, Hidehiro; Ueda, Shinya; Shoemaker, J Kevin; Miyamoto, Tadayoshi

    2015-09-01

    The purpose of the present study was to examine whether the response of cerebral blood flow to an acute change in perfusion pressure is modified by an acute increase in central blood volume. Nine young, healthy subjects voluntarily participated in this study. To measure dynamic cerebral autoregulation during normocapnic and hypercapnic (5%) conditions, the change in middle cerebral artery mean blood flow velocity was analyzed during acute hypotension caused by two methods: 1) thigh-cuff occlusion release (without change in central blood volume); and 2) during the recovery phase immediately following release of lower body negative pressure (LBNP; -50 mmHg) that initiated an acute increase in central blood volume. In the thigh-cuff occlusion release protocol, as expected, hypercapnia decreased the rate of regulation, as an index of dynamic cerebral autoregulation (0.236 ± 0.018 and 0.167 ± 0.025 s(-1), P = 0.024). Compared with the cuff-occlusion release, the acute increase in central blood volume (relative to the LBNP condition) with LBNP release attenuated dynamic cerebral autoregulation (P = 0.009). Therefore, the hypercapnia-induced attenuation of dynamic cerebral autoregulation was not observed in the LBNP release protocol (P = 0.574). These findings suggest that an acute change in systemic blood distribution modifies dynamic cerebral autoregulation during acute hypotension. PMID:26159757

  3. Cerebral blood volume, genotype and chemosensitivity in oligodendroglial tumours

    Energy Technology Data Exchange (ETDEWEB)

    Jenkinson, Michael D. [Walton Centre for Neurology and Neurosurgery, Department of Neurosurgery, Liverpool (United Kingdom); University of Liverpool, Division of Neuroscience, Liverpool (United Kingdom); Smith, Trevor S. [Walton Centre for Neurology and Neurosurgery, Department of Neuroradiology, Liverpool (United Kingdom); Joyce, Kathy A.; Fildes, Diane [JK Douglas Laboratories, Clatterbridge Cancer Research Trust, Wirral (United Kingdom); Broome, John [Walton Centre for Neurology and Neurosurgery, Department of Neuropathology, Liverpool (United Kingdom); Plessis, Daniel G. du [University of Liverpool, Division of Neuroscience, Liverpool (United Kingdom); Haylock, Brian; Husband, David J. [Clatterbridge Hospital, Clatterbridge Centre for Oncology, Neuro-Oncology, Wirral (United Kingdom); Warnke, Peter C. [Leibniz Institute for Neurobiology, Magdeburg (Germany); Walker, Carol [University of Liverpool, Division of Neuroscience, Liverpool (United Kingdom); JK Douglas Laboratories, Clatterbridge Cancer Research Trust, Wirral (United Kingdom)

    2006-10-15

    The biological factors responsible for differential chemoresponsiveness in oligodendroglial tumours with or without the -1p/-19q genotype are unknown, but tumour vascularity may contribute. We aimed to determine whether dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) could distinguish molecular subtypes of oligodendroglial tumour, and examined the relationship between relative cerebral blood volume (rCBV) and outcome following procarbazine, lomustine and vincristine (PCV) chemotherapy. Pretherapy rCBV was calculated and inter- and intraobserver variability assessed. Allelic imbalance in 1p36, 19q13, 17p13, 10p12-15, and 10q22-26 and p53 mutation (exons 5-8) were determined. rCBV was compared with genotype and clinicopathological characteristics (n=37) and outcome following PCV chemotherapy (n=33). 1p/19q loss was seen in 6/9 grade II oligodendrogliomas, 6/14 grade II oligoastrocytomas, 4/4 grade III oligodendrogliomas, and 3/10 grade III oligoastrocytomas. rCBV measurements had good inter- and intraobserver variability, but did not distinguish histology subtype or grade. Tumours with 1p/19q loss had higher rCBV values (Student's t-test P=0.001). Receiver operating characteristic analysis revealed a cut-off of 1.59 for identifying genotype (sensitivity 92%, specificity 76%). Tumours with high and low rCBV showed response to chemotherapy. The -1p/-19q genotype, but not rCBV, was strongly associated with response, progression-free and overall survival following PCV chemotherapy. Tumours with high rCBV and intact 1p/19q were associated with shorter progression-free and overall patient survival than those with intact 1p/19q and low rCBV or high rCBV and 1p/19q loss. (orig.)

  4. Hydration and blood volume effects on human thermoregulation in the heat: Space applications

    Science.gov (United States)

    Sawka, Michael N.; Gonzalez, Richard R.; Pandolf, Kent B.

    1994-01-01

    Astronauts exposed to prolonged weightlessness will experience deconditioning, dehydration, and hypovolemia which all adversely affect thermoregulation. These thermoregulatory problems can be minimized by several countermeasures that manipulate body water and vascular volumes. USARIEM scientists have extensively studied dehydration effects and several possible countermeasures including hyperhydration, plasma and erythrocyte volume expansion. This paper reviews USARIEM research into these areas.

  5. Calculation of the Residual Blood Volume after Acute, Non-Ongoing Hemorrhage Using Serial Hematocrit Measurements and the Volume of Isotonic Fluid Infused: Theoretical Hypothesis Generating Study

    OpenAIRE

    Oh, Won Sup; Chon, Sung-Bin

    2016-01-01

    Fluid resuscitation, hemostasis, and transfusion is essential in care of hemorrhagic shock. Although estimation of the residual blood volume is crucial, the standard measuring methods are impractical or unsafe. Vital signs, central venous or pulmonary artery pressures are inaccurate. We hypothesized that the residual blood volume for acute, non-ongoing hemorrhage was calculable using serial hematocrit measurements and the volume of isotonic solution infused. Blood volume is the sum of volumes...

  6. Simulation of Arc Rotation and Its Effects on Pressure of Expansion Volume in an Auto-Expansion SF6 Circuit Breaker

    Science.gov (United States)

    Zhang, Junmin; Chi, Chengbin; Guan, Yonggang; Liu, Weidong; Wu, Junhui

    2016-03-01

    A 3D Magnetohydrodynamics (MHD) arc model in conjunction with an arc movement model is applied to simulate the arc rotation as well as to solve its effect on the pressure in an auto-expansion circuit breaker. The rotation of the arc driven by an external electromagnetic force is simulated in the case with 200 kA of the short circuit current and 16 ms of arc duration. The arc rotating process and the speed of arc rotation have been obtained in the simulation. A comparison of the pressure in the expansion volume with and without an external magnetic field has been carried out based on the calculation results of two cases. The results of the simulation reveal that the arc rotation, which causes more energy exchange between the arc and its surrounding gas, can evidently bring about the pressurization in the expansion volume, which would contribute to more effective arc quenching at current zero and further reducing operation power. supported by National Natural Science Foundation of China (Nos. 51177005 and 51477004)

  7. 3-D volume reconstruction of skin lesions for melanin and blood volume estimation and lesion severity analysis.

    Science.gov (United States)

    D'Alessandro, Brian; Dhawan, Atam P

    2012-11-01

    Subsurface information about skin lesions, such as the blood volume beneath the lesion, is important for the analysis of lesion severity towards early detection of skin cancer such as malignant melanoma. Depth information can be obtained from diffuse reflectance based multispectral transillumination images of the skin. An inverse volume reconstruction method is presented which uses a genetic algorithm optimization procedure with a novel population initialization routine and nudge operator based on the multispectral images to reconstruct the melanin and blood layer volume components. Forward model evaluation for fitness calculation is performed using a parallel processing voxel-based Monte Carlo simulation of light in skin. Reconstruction results for simulated lesions show excellent volume accuracy. Preliminary validation is also done using a set of 14 clinical lesions, categorized into lesion severity by an expert dermatologist. Using two features, the average blood layer thickness and the ratio of blood volume to total lesion volume, the lesions can be classified into mild and moderate/severe classes with 100% accuracy. The method therefore has excellent potential for detection and analysis of pre-malignant lesions. PMID:22829392

  8. Altered baseline blood volume and the norepinephrine response to stress in humans

    Science.gov (United States)

    Vernikos, J.; Convertino, V. A.

    1992-01-01

    A hypothesis is proposed that a primary physiological purpose of the neural and endocrine response to stressors is the preservation of the blood volume/blood pressure relationship. Changes in blood volume caused by an adaptation to the environmental challenge serve to modulate the neural and endocrine responsiveness to stress. Relationships between changes in vascular volume, vasoconstriction, and norepinephrine (NE) responses during acute and chronic exposure to various stressors are examined. It is noted that the hypothesis is based on numerous observations rather than definitive cause-effect experiments and further investigation is required to prove it.

  9. C-arm flat detector computed tomography parenchymal blood volume imaging: the nature of parenchymal blood volume parameter and the feasibility of parenchymal blood volume imaging in aneurysmal subarachnoid haemorrhage patients

    Energy Technology Data Exchange (ETDEWEB)

    Kamran, Mudassar; Byrne, James V. [University of Oxford, Nuffield Department of Surgical Sciences, Oxford (United Kingdom)

    2015-09-15

    C-arm flat detector computed tomography (FDCT) parenchymal blood volume (PBV) measurements allow assessment of cerebral haemodynamics in the neurointerventional suite. This paper explores the feasibility of C-arm computed tomography (CT) PBV imaging and the relationship between the C-arm CT PBV and the MR-PWI-derived cerebral blood volume (CBV) and cerebral blood flow (CBF) parameters in aneurysmal subarachnoid haemorrhage (SAH) patients developing delayed cerebral ischemia (DCI). Twenty-six patients with DCI following aneurysmal SAH underwent a research C-arm CT PBV scan using a biplane angiography system and contemporaneous MR-PWI scan as part of a prospective study. Quantitative whole-brain atlas-based volume-of-interest analysis in conjunction with Pearson correlation and Bland-Altman tests was performed to explore the agreement between C-arm CT PBV and MR-derived CBV and CBF measurements. All patients received medical management, while eight patients (31 %) underwent selective intra-arterial chemical angioplasty. Colour-coded C-arm CT PBV maps were 91 % sensitive and 100 % specific in detecting the perfusion abnormalities. C-arm CT rPBV demonstrated good agreement and strong correlation with both MR-rCBV and MR-rCBF measurements; the agreement and correlation were stronger for MR-rCBF relative to MR-rCBV and improved for C-arm CT PBV versus the geometric mean of MR-rCBV and MR-rCBF. Analysis of weighted means showed that the C-arm CT PBV has a preferential blood flow weighting (∼60 % blood flow and ∼40 % blood volume weighting). C-arm CT PBV imaging is feasible in DCI following aneurysmal SAH. PBV is a composite perfusion parameter incorporating both blood flow and blood volume weightings. That PBV has preferential (∼60 %) blood flow weighting is an important finding, which is of clinical significance when interpreting the C-arm CT PBV maps, particularly in the setting of acute brain ischemia. (orig.)

  10. Orthostatic leg blood volume changes assessed by near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Truijen, J; Kim, Y S; Krediet, C T P;

    2012-01-01

    Standing up shifts blood to dependent parts of the body, and blood vessels in the leg become filled. The orthostatic blood volume accumulation in the small vessels is relatively unknown, although these may contribute significantly. We hypothesized that in healthy humans exposed to the upright pos...... suggest a non-linear accumulation of blood volume in the small vessels of the leg, with an initial fast phase followed by a more gradual increase at least partly contributing to the relocation of fluid during orthostatic stress....

  11. Blood volume, plasma volume and circulation time in a high-energy-demand teleost, the yellowfin tuna (Thunnus albacares)

    Science.gov (United States)

    Brill; Cousins; Jones; p

    1998-06-01

    We measured red cell space with 51Cr-labeled red blood cells, and dextran space with 500 kDa fluorescein-isothiocyanate-labeled dextran (FITC-dextran), in two groups of yellowfin tuna (Thunnus albacares). Red cell space was 13.8+/-0.7 ml kg-1 (mean +/- s.e.m.) Assuming a whole-body hematocrit equal to the hematocrit measured at the ventral aortic sampling site and no significant sequestering of 51Cr-labeled red blood cells by the spleen, blood volume was 46. 7+/-2.2 ml kg-1. This is within the range reported for most other teleosts (30-70 ml kg-1), but well below that previously reported for albacore (Thunnus alalunga, 82-197 ml kg-1). Plasma volume within the primary circulatory system (calculated from the 51Cr-labeled red blood cell data) was 32.9+/-2.3 ml kg-1. Dextran space was 37.0+/-3.7 ml kg-1. Because 500 kDa FITC-dextran appeared to remain within the vascular space, these data imply that the volume of the secondary circulatory system of yellowfin tuna is small, and its exact volume is not measurable by our methods. Although blood volume is not exceptional, circulation time (blood volume/cardiac output) is clearly shorter in yellowfin tuna than in other active teleosts. In a 1 kg yellowfin tuna, circulation time is approximately 0.4 min (47 ml kg-1/115 ml min-1 kg-1) compared with 1. 3 min (46 ml kg-1/35 ml min-1 kg-1) in yellowtail (Seriola quinqueradiata) and 1.9 min (35 ml kg-1/18 ml min-1 kg-1) in rainbow trout (Oncorhynchus mykiss). In air-breathing vertebrates, high metabolic rates are necessarily correlated with short circulation times. Our data are the first to imply that a similar relationship occurs in fishes. PMID:9450974

  12. The effect of chronic erythrocytic polycythemia and high altitude upon plasma and blood volumes.

    Science.gov (United States)

    Burton, R. R.; Smith, A. H.

    1972-01-01

    Comparison of two kinds of physiological chronic erythrocytic polycythemias in order to differentiate the specific effect of erythrocytic polycythemia from the general effects of high altitude upon the plasma volume. The two kinds were produced hormonally in female chickens, at sea level, or by protracted high-altitude exposures. It appears that the vascular system of the body may account for an increase in red blood cell mass either by reduction in plasma volume, or by no change in plasma volume, resulting in differential changes in total blood volumes.

  13. Ventilatory response in metabolic acidosis and cerebral blood volume in humans.

    NARCIS (Netherlands)

    Ven, M.T.P. van de; Colier, W.N.J.M.; Sluijs, M.C. van der; Oeseburg, B.; Folgering, H.T.M.

    2001-01-01

    The relationship between alterations in cerebral blood volume (CBV) and central chemosensitivity regulation was studied under neutral metabolic conditions and during metabolic acidosis. Fifteen healthy subjects (5610 years) were investigated. To induce metabolic acidosis, ammonium chloride (NH(4)Cl)

  14. Mechanisms of proximal tubule sodium transport regulation that link extracellular fluid volume and blood pressure

    OpenAIRE

    McDonough, Alicia A

    2010-01-01

    One-hundred years ago, Starling articulated the interdependence of renal control of circulating blood volume and effective cardiac performance. During the past 25 years, the molecular mechanisms responsible for the interdependence of blood pressure (BP), extracellular fluid volume (ECFV), the renin-angiotensin system (RAS), and sympathetic nervous system (SNS) have begun to be revealed. These variables all converge on regulation of renal proximal tubule (PT) sodium transport. The PT reabsorbs...

  15. Pulmonary capillary blood volume in patients with probable pulmonary Kaposi's sarcoma.

    OpenAIRE

    Camus, F.; de Picciotto, C.; Gerbe, J; S Roy; Bouchaud, O.; E. Casalino; Perronne, C

    1996-01-01

    BACKGROUND: An increase in pulmonary capillary blood volume secondary to angiogenesis has been described in Kaposi's sarcoma. The value of the pulmonary capillary blood volume as an early marker of pulmonary Kaposi's sarcoma was evaluated. METHODS: In a prospective study 45 HIV positive patients (nine asymptomatic for Kaposi's sarcoma, 29 with cutaneous or mucocutaneous Kaposi's sarcoma, and seven with pulmonary Kaposi's sarcoma), underwent pulmonary function tests and determination of transf...

  16. Loss of alveolar membrane diffusing capacity and pulmonary capillary blood volume in pulmonary arterial hypertension

    OpenAIRE

    Farha Samar; Laskowski Daniel; George Deepa; Park Margaret M; Tang WH Wilson; Dweik Raed A; Erzurum Serpil C

    2013-01-01

    Abstract Background Reduced gas transfer in patients with pulmonary arterial hypertension (PAH) is traditionally attributed to remodeling and progressive loss of pulmonary arterial vasculature that results in decreased capillary blood volume available for gas exchange. Methods We tested this hypothesis by determination of lung diffusing capacity (DL) and its components, the alveolar capillary membrane diffusing capacity (Dm) and lung capillary blood volume (Vc) in 28 individuals with PAH in c...

  17. Cerebral blood volume measured using near-infrared spectroscopy and radiolabels in the immature lamb brain.

    Science.gov (United States)

    Barfield, C P; Yu, V Y; Noma, O; Kukita, J; Cussen, L J; Oates, A; Walker, A M

    1999-07-01

    Near-infrared spectroscopy (NIRS) is a technique that is increasingly being used for the noninvasive measurement of cerebral blood volume (CBV) in newborn infants, but it has not been fully validated against established methods. These experiments in immature lambs (gestation 92+/-1 d, mean+/-SEM) compared CBV measured using NIRS-derived estimates of oxygenated Hb (n = 5) with CBV estimated with radiolabeled indicators (125I-labeled serum albumin and 51Cr-labeled red blood cells, n = 10). Total brain CBV (mL/100 g tissue) measured using NIRS was 2.5+/-0.2 compared with 2.5+/-0.2 using radiolabels (NS). Regional tissue plasma, red blood cells, and whole blood volumes from radiolabels varied significantly (p cerebellum > cortex > brain stem = midbrain > white matter. Regional plasma and red blood cell distributions were similar to whole blood, being highest in choroid plexus (13.0+/-1.6 and 3.2+/-0.9, respectively), and least in white matter (0.8+/-0.1 and 0, respectively). These data from the immature lamb brain indicate that total CBV measured with NIRS is essentially identical with the volumes obtained using intravascular radiolabels. Among cerebral regions, white matter contributes little to the global blood volume measured with NIRS because its red blood cell content is very low. PMID:10400134

  18. Quantification of cardiopulmonary blood volume turnover using dynamic PET

    DEFF Research Database (Denmark)

    Harms, Hans; Tolbod, Lars Poulsen; Kero, Tanja;

    index, the central circulatory turnover (CCT) which represents the fractional exchange of blood per stroke within the cardiopulmonary blood pool and can be measured from any dynamic PET scan. Methods: Data from 111 clinical patients were analysed retrospectively. Patients underwent a 6-min 15O...... and RV time-activity curves were extracted after which their first-pass peaks were isolated and the centroid of each peak was obtained. Mean pulmonary transit time (MPTT, min) was defined as the difference between the LV centroid and the RV centroid and CCT was defined as 1/(MPTT*heart rate). Results.......001). Decrease of CCT was especially pronounced in severely ischemic patients already at rest Conclusion: Pulmonary transit times and central circulatory turnover can be measured automatically using dynamic PET. Since both are correlated with severity of myocardial ischemia already at rest, they appear to...

  19. Volume-dependent hemodynamic effects of blood collection in canine donors - evaluation of 13% and 15% of total blood volume depletion

    Directory of Open Access Journals (Sweden)

    RUI R.F. FERREIRA

    2015-03-01

    Full Text Available Background: There is no consensus regarding the blood volume that could be safely donated by dogs, ranging from 11 to 25% of its total blood volume (TBV. No previous studies evaluated sedated donors.Aim: To evaluate the hemodynamic effects of blood collection from sedated and non-sedated dogs and to understand if such effects were volume-dependent.Materials and Methods: Fifty three donations of 13% of TBV and 20 donations of 15% TBV were performed in dogs sedated with diazepam and ketamine. Additionally, a total of 30 collections of 13% TBV and 20 collections of 15% TBV were performed in non-sedated dogs. Non-invasive arterial blood pressures and pulse rates were registered before and 15 min after donation. Results: Post-donation pulse rates increased significantly in both sedated groups, with higher differences in the 15% TBV collections. Systolic arterial pressures decreased significantly in these groups, while diastolic pressures increased significantly in 13% TBV donations. Non-sedated groups revealed a slight, but significant, SBP decrease. No clinical signs related to donations were registered.Conclusion: These results suggest that the collection of 15% TBV in sedated donors induces hemodynamic variations that may compromise the harmlessness of the procedure, while it seems to be a safe procedure in non-sedated dogs.

  20. Blood volume increase in salt-induced pulmonary hypertension, heart failure and ascites in broiler and White Leghorn chickens.

    Science.gov (United States)

    Mirsalimi, S M; O'Brien, P J; Julian, R J

    1993-01-01

    In this study we tested the hypothesis that excess dietary salt produces an expansion of extracellular fluid volume which may be associated with pulmonary hypertension-induced right ventricular failure in chickens with rapid growth rates. One-week-old broiler and White Leghorn chickens were given 0.5% salt in their drinking water for three weeks. Saline water had a minimal effect on White Leghorns. The hypothesis appears to be correct since salt-treatment in broilers resulted in up to 30% expansion in blood volume and there was 50% mortality from pulmonary hypertension-induced right ventricular failure and ascites. There was marked (up to 88% in some broilers) right ventricular hypertrophy, an indicator of pulmonary hypertension. There was less left ventricular hypertrophy as shown by an increase in the ratio of the right to total ventricle weight. There was up to 32% decrease in growth rate. There was renal hypertrophy in the salt-treated birds as shown by a higher kidney to body weight ratio. PMID:8490804

  1. By Different Cellular Mechanisms, Lymphatic Vessels Sprout by Endothelial Cell Recruitment Whereas Blood Vessels Grow by Vascular Expansion

    Science.gov (United States)

    Parsons-Wingerter, Patricia; McKay, Terri L.; Leontiev, Dmitry; Condrich, Terence K.; DiCorleto, Paul E.

    2005-01-01

    The development of effective vascular therapies requires the understanding of all modes of vessel formation contributing to vasculogenesis, angiogenesis (here termed hemangiogenesis) and lymphangiogenesis. We show that lymphangiogenesis proceeds by blind-ended vessel sprouting via recruitment of isolated endothelial progenitor cells to the tips of growing vessels, whereas hemangiogenesis occurs by non-sprouting vessel expansion from the capillary network, during middevelopment in the quail chorioallantoic membrane (CAM). Blood vessels expanded out of capillaries that displayed transient expression of alpha smooth muscle actin (alphaSMA), accompanied by mural recruitment of migratory progenitor cells expressing SMA. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptors VEGFR-1 and VEGFR-2, alphaSMA (expressed on CAM blood vessels but not on lymphatics), homeobox transcription factor Prox-1 (specific to CAM lymphatic endothelium), and the quail hematopoetic/vascular marker, QH-1. Expression of VEGFR-1 was highly restricted to blood vessels (primarily capillaries). VEGFR-2 was expressed intensely in isolated hematopoietic cells, lymphatic vessels and moderately in blood vessels. Prox-1 was absent from endothelial progenitor cells prior to lymphatic recruitment. Although vascular endothelial growth factor-165 (VEGF(sub 165)) is a key regulator of numerous cellular processes in hemangiogenesis and vasculogenesis, the role of VEGF(sub 165) in lymphangiogenesis is less clear. Exogenous VEGF(sub 165) increased blood vessel density without changing endogenous modes of vascular/lymphatic vessel formation or marker expression patterns. However, VEGF(sub 165) did increase the frequency of blood vascular anastomoses and strongly induced the antimaturational dissociation of lymphatics from blood vessels, with frequent formation of homogeneous lymphatic networks.

  2. Measurement of blood flow volume of ocular muscles by Xe-133 clearance method

    International Nuclear Information System (INIS)

    The blood flow volume of the ocular muscles was measured in 8 normal volunteers and 12 cases with miscellaneous opthalmic diseases by Xe-133 clearance method. The average of blood flow volume in the normal subjects was 7.45 ± 2.07 ml/min/100 g, and the blood flow volume ratio of right eye to left eye was 0.94 ± 0.07. The blood flow volume of the ocular muscles was decreased in the cases with stenosis of the internal carotid artery (n = 4, 4.3 ± 2.1 ml/min/100 g), glaucoma (n = 3, 4.7 ± 4.1 ml/min/100 g), arterial scleroses (n = 2, 3.8 ± 0.2 ml/min/100 g) and Takayasu's disease (n = 2, 5.6 ± 0.4 ml/min/100 g), and was increased in the acute inflammatory disease (n = 2, 21.5 ± 2.5 ml/min/100 g). Measurement of the blood flow volume of the ocular muscles using Xe-133 clearance method is useful to evaluate the circulatory abnormality in the ophthalmic diseases. (author)

  3. Hemodynamic and ADH responses to central blood volume shifts in cardiac-denervated humans

    Science.gov (United States)

    Convertino, V. A.; Thompson, C. A.; Benjamin, B. A.; Keil, L. C.; Savin, W. M.; Gordon, E. P.; Haskell, W. L.; Schroeder, J. S.; Sandler, H.

    1990-01-01

    Hemodynamic responses and antidiuretic hormone (ADH) were measured during body position changes designed to induce blood volume shifts in ten cardiac transplant recipients to assess the contribution of cardiac and vascular volume receptors in the control of ADH secretion. Each subject underwent 15 min of a control period in the seated posture, then assumed a lying posture for 30 min at 6 deg head down tilt (HDT) followed by 20 min of seated recovery. Venous blood samples and cardiac dimensions (echocardiography) were taken at 0 and 15 min before HDT, 5, 15, and 30 min of HDT, and 5, 15, and 30 min of seated recovery. Blood samples were analyzed for hematocrit, plasma osmolality, plasma renin activity (PRA), and ADH. Resting plasma volume (PV) was measured by Evans blue dye and percent changes in PV during posture changes were calculated from changes in hematocrit. Heart rate (HR) and blood pressure (BP) were recorded every 2 min. Results indicate that cardiac volume receptors are not the only mechanism for the control of ADH release during acute blood volume shifts in man.

  4. Measurement of regional extravascular lung density and of pulmonary blood volume with positron emitting isotopes

    International Nuclear Information System (INIS)

    Studies of pulmonary blood volume changes with exercice can be performed after labelling of the blood pool by 11CO inhalation. Positron transaxial tomography permits the quantitative study of density distribution of the chest and of the pulmonary blood volume. This paper represents our preliminary experience with these techniques on models and control patients. We have first verified the linearity of transmission for density distribution below one. The tomographic examination first records a transmission image, then an emission image on the same section. We next normalize emission and transmission values on a region of unit density corresponding to blood: then we substract the emission from the transmission values to measure the extravascular pulmonary density. With crystal probes we record pulmonary blood volume variations before, during and after exercise. Peripheral hemodynamic variations explain the change recorded at the begining and at the end of exercise. Combination of these two techniques should help us to better study the importance of the acute changes in the ''formation'' of pulmonary oedema and its influence on regional pulmonary blood volume

  5. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    Science.gov (United States)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro- reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationships of the cardiopulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venotis Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). Altered vascular volume had no effect on response relations of the carotid-cardiac baroreflex but did alter the gain of the cardiopulmonary baroreflex (-7.93 q 1.71, -4.36 q 1.38, and -2.56 q 1.59 peripheral resistance units/mmHg for hypovolemic, normovolemic, and hypervolemic, respectively) independent of shifts in baseline FVR and PVP. These results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulnionary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

  6. Blood Contrast Agents Enhance Intrinsic Signals in the Retina: Evidence for an Underlying Blood Volume Component

    OpenAIRE

    Schallek, Jesse; Ts'o, Daniel

    2011-01-01

    Systemic injections of blood contrast agents nigrosin and indocyanine green increased stimulus-evoked reflectance signals in the retina. The enhancement of signal strength is consistent with neurovascular coupling in response to visual stimulation.

  7. Modelling the thermo-mechanical volume change behaviour of compacted expansive clays

    CERN Document Server

    Tang, Anh-Minh; 10.1680/geot.2009.59.3.185

    2009-01-01

    Compacted expansive clays are often considered as a possible buffer material in high-level deep radioactive waste disposals. After the installation of waste canisters, the engineered clay barriers are subjected to thermo-hydro-mechanical actions in the form of water infiltration from the geological barrier, heat dissipation from the radioactive waste canisters, and stresses generated by clay swelling under almost confined conditions. The aim of the present work is to develop a constitutive model that is able to describe the behaviour of compacted expansive clays under these coupled thermo-hydro-mechanical actions. The proposed model is based on two existing models: one for the hydro-mechanical behaviour of compacted expansive clays and another for the thermo-mechanical behaviour of saturated clays. The elaborated model has been validated using the thermo-hydro-mechanical test results on the compacted MX80 bentonite. Comparison between the model prediction and the experimental data show that this model is able...

  8. Completion report, Purex and Redox Phase 2 expansion: Jobs 1063 and 1063R. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1955-05-01

    Vitro Corporation of America entered into a contract with the US Atomic Energy Commission on July 2, 1952 to furnish architect-engineering services in connection with the design and construction of a new chemical plant facility located in the 200 Area of the Hanford Works, Richland, Washington. This contract provided for engineering of facilities utilizing the Purex process to separate and decontaminate uranium and plutonium contained in slugs irradiated in Hanford reactors. Later, Vitro was requested to provide architect-engineering services for an expansion of the previously constructed Redox separation facility. This work, designated as ``Redox Phase II Expansion,`` was authorized by Modification No. 1 to the above contract and was executed April 17, 1953. This completion report has been prepared at the request of the AEC and is intended to provide a convenient source of information concerning the administrative history and engineering features of the Purex plant and the Redox Phase II Expansion.

  9. Pulmonary blood volume and transit time in cirrhosis: relation to lung function

    DEFF Research Database (Denmark)

    Møller, Søren; Burchardt, H; Øgard, CG;

    2006-01-01

    BACKGROUND/AIMS: In cirrhosis a systemic vasodilatation leads to an abnormal distribution of the blood volume with a contracted central blood volume. In addition, the patients have a ventilation/perfusion imbalance with a low diffusing capacity. As the size of the pulmonary blood volume (PBV) has...... not been determined separately we assessed PBV and pulmonary transit time (PTT) in relation to lung function in patients with cirrhosis and in controls. METHODS: Pulmonary and cardiac haemodynamics and transit times were determined by radionuclide techniques in 22 patients with alcoholic cirrhosis and...... cirrhosis. The relation between PBV and PTT and the low diffusing capacity suggests the pulmonary vascular compartment as an important element in the pathophysiology of the lung dysfunction in cirrhosis....

  10. Pulmonary blood volume and transit time in cirrhosis: relation to lung function

    DEFF Research Database (Denmark)

    Møller, Søren; Burchardt, H; Øgard, CG;

    2006-01-01

    BACKGROUND/AIMS: In cirrhosis a systemic vasodilatation leads to an abnormal distribution of the blood volume with a contracted central blood volume. In addition, the patients have a ventilation/perfusion imbalance with a low diffusing capacity. As the size of the pulmonary blood volume (PBV) has...... cirrhosis. The relation between PBV and PTT and the low diffusing capacity suggests the pulmonary vascular compartment as an important element in the pathophysiology of the lung dysfunction in cirrhosis....... not been determined separately we assessed PBV and pulmonary transit time (PTT) in relation to lung function in patients with cirrhosis and in controls. METHODS: Pulmonary and cardiac haemodynamics and transit times were determined by radionuclide techniques in 22 patients with alcoholic cirrhosis and...

  11. Exercise induced pulmonary, hepatic and splenic blood volume changes in diabetic subjects

    International Nuclear Information System (INIS)

    Exercise induced blood volume changes in visceral organs were determined by scintillation gamma camera imaging in 11 normal healthy male volunteers and 15 NIDDM male diabetics without clinical signs of neuropathy. After in-vivo labelling of red cells with Technetium-99m, the data was acquired in the supine position at rest and immediately after graded upright ergometer bicycle exercise. From rest to peak exercise, pulmonary blood volume increased 19% and 75% in normal volunteers of less than and more than 40 years of age respectively. A decrease of 18% and 42% was noted in the hepatic and splenic blood volume respectively, regardless of the age, in the normal subjects. In contrast to normals, the diabetic patients showed in response to peak exercise as compared to age-matched controls. A significant difference in the drop in pulmonary blood volume 82.37% and 90% was observed between diabetics of more than and less than 7 years duration respectively. The liver and spleen of the diabetic subjects revealed a lesser decrease of 87.6% and 71.33% respectively in response to peak stress in comparison to the age matched controls. The reduction in the hepatic and splenic blood volume was equally evident in diabetics of more than or less than 50 years of age and it was statistically nonsignificant. This study demonstrates that the normal pattern of redistribution of blood volume in response to maximum exercise in diabetics is altered such that there is restricted pulmonary perfusion and diminished vasoconstriction of the hepato splenic vascular bed and the changes in the pulmonary circulation are related to the duration of the diabetics rather than the age of the patient. (author)

  12. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    Science.gov (United States)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro-reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationship, of the cardio-pulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venous Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). The results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulmonary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

  13. Lung fractional moving blood volume in normally grown and growth restricted foetuses.

    OpenAIRE

    Hernandez-Andrade, Edgar; Thuring, Ann; Jansson, Tomas; Lingman, Göran; Marsal, Karel

    2004-01-01

    Objective: To examine foetal lung blood perfusion using power Doppler ultrasound (PDU) and to compare fractional moving blood volume (FMBV) and mean pixel intensity (MPI) estimations in the lungs of normally grown (NG) foetuses and foetuses with intrauterine growth restriction (IUGR) and also to correlate foetal lung FMBV and MPI with respiratory complications after birth. Methods: Lungs of 47 NG and 25 IUGR foetuses after 32 weeks of gestation were examined with PDU. FMBV and MPI were...

  14. Mesenchymal Stem Cell-Derived Microvesicles Support Ex Vivo Expansion of Cord Blood-Derived CD34+ Cells

    Directory of Open Access Journals (Sweden)

    Hui Xie

    2016-01-01

    Full Text Available Mesenchymal stem cells (MSCs are known to support the characteristic properties of hematopoietic stem and progenitor cells (HSPCs in the bone marrow hematopoietic microenvironment. MSCs are used in coculture systems as a feeder layer for the ex vivo expansion of umbilical cord blood (CB to increase the relatively low number of HSPCs in CB. Findings increasingly suggest that MSC-derived microvesicles (MSC-MVs play an important role in the biological functions of their parent cells. We speculate that MSC-MVs may recapitulate the hematopoiesis-supporting effects of their parent cells. In the current study, we found MSC-MVs containing microRNAs that are involved in the regulation of hematopoiesis. We also demonstrated that MSC-MVs could improve the expansion of CB-derived mononuclear cells and CD34+ cells and generate a greater number of primitive progenitor cells in vitro. Additionally, when MSC-MVs were added to the CB-MSC coculture system, they could improve the hematopoiesis-supporting effects of MSCs. These findings highlight the role of MSC-MVs in the ex vivo expansion of CB, which may offer a promising therapeutic approach in CB transplantation.

  15. Blood volume determination with two radioisotopes: application to non-cardiogenic shock

    International Nuclear Information System (INIS)

    Knowledge of the circulating blood volume may be of great assistance in the study of clinical shock. The isotope dilution principle is used to measure both plasma and red cell volume. Considering the increased capillary permeability in patients in shock, it may be of considerable value to quantify the diffusion of liquid through the capillary walls. A double determination of the volume of distribution of the tracer is to be envisaged. Two methods are described. The first one uses a non-diffusible tracer (sup(99m)Tc-labelled red cells) confined to the intravascular space, giving a measure of the intravascular blood volume. The latter uses 131I-labelled serum albumin which remains, usually, in the vascular bed, but is able to diffuse through the pores of the capillary membrane, because of its low molecular weight. A resulting increase of the tracer volume distribution, with regard to this capillary diffusion is considered. A comparison of the two methods used simultaneously appear to provide information on the possible liquid diffusion in clinical shock. The results obtained in several pathological conditions are described. They enable conclusion to be drawn on the possibility of errors introduced by the use of 131I-labelled serum albumin alone in determining the circulating blood volume in clinical shock

  16. Magnetization reversal and negative volume thermal expansion in Fe doped Ca2RuO4

    Science.gov (United States)

    Qi, T. F.; Yuan, S. J.; Ye, F.; Chi, S.; Terzic, J.; Zhang, H.; Zhao, Z.; Liu, X.; Parkin, S.; Mao, W. L.; Cao, G.

    We report structural, magnetic, transport and thermal properties of single-crystal Ca2Ru1-xFexO4 (0 pressure, magnetic field and temperature. The central findings of this work are a pronounced magnetization reversal and a negative thermal expansion that are induced by Fe doping. Our results including neutron diffraction data suggest that the magnetization reversal is primarily a result of different temperature dependences of two antiparallel, competing Ru and Fe sublattices and that the negative thermal expansion is achieved via magnetic and metal-insulator transitions. We will present and discuss our results with comparison drawn with relevant systems. This work was supported by the NSF via Grant No. DMR-1265162.

  17. Human umbilical cord blood-derived f-macrophages retain pluripotentiality after thrombopoietin expansion

    International Nuclear Information System (INIS)

    We have previously characterized a new type of stem cell from human peripheral blood, termed fibroblast-like macrophage (f-MΦ). Here, using umbilical cord blood as a source, we identified cells with similar characteristics including expression of surface markers (CD14, CD34, CD45, CD117, and CD163), phagocytosis, and proliferative capacity. Further, thrombopoietin (TPO) significantly stimulated the proliferation of cord blood-derived f-MΦ (CB f-MΦ) at low dosage without inducing a megakaryocytic phenotype. Additional experiments demonstrated that TPO-expanded cord blood-derived f-MΦ (TCB f-MΦ) retained their surface markers and differentiation ability. Treatment with vascular endothelial cell growth factor (VEGF) gave rise to endothelial-like cells, expressing Flt-1, Flk-1, von Willebrand Factor (vWF), CD31, acetylated low density lipoprotein internalization, and the ability to form endothelial-like cell chains. In the presence of lipopolyssacharide (LPS) and 25 mM glucose, the TCB f-MΦ differentiated to express insulin mRNA, C-peptide, and insulin. In vitro functional analysis demonstrated that these insulin-positive cells could release insulin in response to glucose and other secretagogues. These findings demonstrate a potential use of CB f-MΦ and may lead to develop new therapeutic strategy for treating dominant disease

  18. Acute attenuation of glycocalyx barrier properties increases coronary blood volume independently of coronary flow reserve

    NARCIS (Netherlands)

    J. Brands; J.A.E. Spaan; B.M. van den Berg; H. Vink; J.W.G.E. VanTeeffelen

    2010-01-01

    Brands J, Spaan JA, Van den Berg BM, Vink H, VanTeeffelen JW. Acute attenuation of glycocalyx barrier properties increases coronary blood volume independently of coronary flow reserve. Am J Physiol Heart Circ Physiol 298: H515-H523, 2010. First published November 25, 2009; doi:10.1152/ajpheart.01306

  19. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B; Garde, K; Ring, P B; Henriksen, O

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...

  20. The effect of metallic coatings and crystallinity on the volume expansion of silicon during electrochemical lithiation/delithiation

    KAUST Repository

    McDowell, Matthew T.

    2012-05-01

    Applying surface coatings to alloying anodes for Li-ion batteries can improve rate capability and cycle life, but it is unclear how this second phase affects mechanical deformation during electrochemical reaction. Here, in-situ transmission electron microscopy is employed to investigate the electrochemical lithiation and delithiation of silicon nanowires (NWs) with copper coatings. When copper is coated on only one sidewall, the NW bilayer structure bends during delithiation due to length changes in the silicon. Tensile hoop stress causes conformal copper coatings to fracture during lithiation without undergoing bending deformation. In addition, in-situ and ex-situ observations indicate that a copper coating plays a role in suppressing volume expansion during lithiation. Finally, the deformation characteristics and dimensional changes of amorphous, polycrystalline, and single-crystalline silicon are compared and related to observed electrochemical behavior. This study reveals important aspects of the deformation process of silicon anodes, and the results suggest that metallic coatings can be used to improve rate behavior and to manage or direct volume expansion in optimized silicon anode frameworks. © 2012 Elsevier Ltd.

  1. Acute volume expansion attenuates hyperthermia-induced reductions in cerebral perfusion during simulated hemorrhage

    DEFF Research Database (Denmark)

    Schlader, Zachary J; Seifert, Thomas; Wilson, Thad E; Bundgaard-Nielsen, Morten; Secher, Niels H; Crandall, Craig G

    2013-01-01

    infusion while hyperthermic. Primary dependent variables were mean middle cerebral artery blood velocity (MCAvmean), serving as an index of cerebral perfusion; mean arterial pressure (MAP); and cardiac output (thermodilution). During baseline, hyperthermia reduced MCAvmean (P = 0.001) by 12 ± 9% relative...

  2. Functional photoacoustic tomography for non-invasive imaging of cerebral blood oxygenation and blood volume in rat brain in vivo

    Science.gov (United States)

    Wang, Xueding; Xie, Xueyi; Ku, Geng; Stoica, George; Wang, Lihong V.

    2005-04-01

    Based on the multi-wavelength laser-based photoacoustic tomography, non-invasive in vivo imaging of functional parameters, including the hemoglobin oxygen saturation and the total concentration of hemoglobin, in small-animal brains was realized. The high sensitivity of this technique is based on the spectroscopic differences between oxy- and deoxy-hemoglobin while its spatial resolution is bandwidth-limited by the photoacoustic signals rather than by the optical diffusion as in optical imaging. The point-by-point distributions of blood oxygenation and blood volume in the cerebral cortical venous vessels, altered by systemic physiological modulations including hyperoxia, normoxia and hypoxia, were visualized successfully through the intact skin and skull. This technique, with its prominent intrinsic advantages, can potentially accelerate the progress in neuroscience and provide important new insights into cerebrovascular physiology and brain function that are of great significance to the neuroscience community.

  3. Determination of cardiac output, tissue blood flow, volume and lipid content in Sprague-Dawley rats

    International Nuclear Information System (INIS)

    One critical aspect of physiologically-based pharmacokinetic (PBPK) model development is the choice of values for organ blood flows, cardiac output and tissue volumes for input into models. These values vary depending upon the strain, size, age, and sex of animal for which a PBPK model is being developed. Tissue blood flows, cardiac output, tissue volume, and lipid content were determined in male S-D rats, (350-375 g, N=8). A radiolabel microsphere method utilizing Scandium (46Sc), Tin (113Sn),and Gadolinium (153Gd) was used to determine blood flow. Each rat received 3 radiolabeled injections. After the third injection, animals were sacrificed, and radioactivity in each tissue was determined in a 3-channel gamma counter. Tissues sampled include brain, heart, kidneys, liver, lungs, spleen, pancreas, adrenals, stomach, intestines, colon, testis, bone and skeletal muscle. Cardiac output was 142 ml/min. Blood flow values for eliminating organs were 0.49 (liver), 16.52 (kidney), and 1.77 (lung) ml/min/g tissue. Tissues which had significantly increased blood flow during the dark cycle included femur, abdonimal fat, triceps brachii and abdominal muscles, stomach, spleen and lung. Dissectable fat, organ volume, and organ lipid content were determined in a separate group of rats (N= 8). Volume and lipid content were determined for the same tissues as blood flow. Body fat was 7.35% of bw and extractable lipid content of eliminating organs was 42.3 (liver), 43.4 (kidney), and 35.9 (lung) mg/g tissue. Precise measurements should improve the accuracy of PBPK model predictions, and therfore help in reducing uncertainites in risk assessment of volatile organics and other pollutnats

  4. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices. [Appendices only

    Energy Technology Data Exchange (ETDEWEB)

    Liverman, James L.

    1977-09-01

    Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant. (LK)

  5. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices

    International Nuclear Information System (INIS)

    Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant

  6. Absolute cerebral blood flow and blood volume measured by magnetic resonance imaging bolus tracking: comparison with positron emission tomography values

    DEFF Research Database (Denmark)

    Østergaard, Leif; Smith, D F; Vestergaard-Poulsen, Peter;

    1998-01-01

    blood volume (CBV) estimates obtained using this normalization constant correlated well with values obtained by O-15 labeled carbonmonooxide (C15O) PET. However, PET CBV values were approximately 2.5 times larger than absolute MRI CBV values, supporting the hypothesized sensitivity of MRI to small...... hypercapnic conditions. After dose normalization and introduction of an empirical constant phi Gd, absolute regional CBF was calculated from MRI. The spatial resolution and the signal-to-noise ratio of CBF measurements by MRI were better than by the H215O-PET protocol. Magnetic resonance imaging cerebral...

  7. Angiotensin II type 1 receptors and systemic hemodynamic and renal responses to stress and altered blood volume in conscious rabbits

    Directory of Open Access Journals (Sweden)

    RogerGeorgeEvans

    2011-07-01

    Full Text Available We examined how systemic blockade of type 1 angiotensin (AT1- receptors affects reflex control of the circulation and the kidney. In conscious rabbits, the effects of candesartan on responses of systemic and renal hemodynamics and renal excretory function to acute hypoxia, mild hemorrhage and plasma volume expansion were tested. Candesartan reduced resting mean arterial pressure (MAP, -8 ± 2% without significantly altering cardiac output (CO, increased renal blood flow (RBF, +38 ± 9% and reduced renal vascular resistance (RVR, -32 ± 6%. Glomerular filtration rate (GFR was not significantly altered but sodium excretion (UNa+V increased four-fold. After vehicle treatment, hypoxia (10% inspired O2 for 30 min did not significantly alter MAP or CO, but reduced HR (-17 ± 6%, increased RVR (+33 ± 16% and reduced GFR (-46 ± 16% and UNa+V (-41 ± 17%. Candesartan did not significantly alter these responses. After vehicle treatment, plasma volume expansion increased CO (+35 ± 7%, reduced total peripheral resistance (TPR, -26 ± 5%, increased RBF (+62 ± 23% and reduced RVR (-32 ± 9%, but did not significantly alter MAP or HR. It also increased UNa+V (803 ± 184% yet reduced GFR (-47 ± 9%. Candesartan did not significantly alter these responses. After vehicle treatment, mild hemorrhage did not significantly alter MAP but increased HR (+16 ± 3%, reduced CO (-16 ± 4% and RBF (-18 ± 6%, increased TPR (+18 ± 4% and tended to increase RVR (+18 ± 9%, P = 0.1, but had little effect on GFR or UNa+V. But after candesartan treatment MAP fell during hemorrhage (-19 ± 1%, while neither TPR nor RVR increased, and GFR (-64 ± 18% and UNa+V (-83 ± 10% fell. AT1-receptor activation supports MAP and GFR during hypovolemia. But AT1-receptors appear to play little role in the renal vasoconstriction, hypofiltration and antinatriuresis accompanying hypoxia, or the systemic and renal vasodilatation and natriuresis accompanying plasma volume expansion.

  8. Internal target volume determined with expansion margins beyond composite gross tumor volume in three-dimensional conformal radiotherapy for lung cancer

    International Nuclear Information System (INIS)

    Purpose: Gross tumor volume (GTV) of lung cancer defined by fast helical CT scan represents an image of moving tumor captured at a point in active respiratory movement. However, the method for defining internal margins beyond GTV to account for its expected physiologic movement and all variations in size and shape during the administration of radiation has not been established. The goal of this study was to determine the internal margins with expansion margins beyond individual GTVs defined with (1) fast scan at shallow free breathing (2) breath-hold scans at the end of tidal volume inspiration and expiration, and (3) 4-s slow scan to approximate the composite GTV of all scans. Methods and materials: A series of sequential CT scans were acquired with (1) a fast helical scan at shallow free breathing and (2) breath-hold scans at the end of tidal volume expiration and inspiration for the first 6 patients, and (3) a 4-s slow scan at quiet free breathing, which was added for the latter 7 patients. We fused breath-hold scans and the 4-s slow scan to the fast scan at shallow free breathing to generate the composite GTV. Margins necessary to encompass the composite GTV beyond individual GTVs defined by either fast scan at quiet free breathing, breath-hold scans, or the 4-s slow scan at quiet free breathing were defined as expansion or internal margins and termed the internal target volumes. The centroid of the tumor volume was also used as another reference for tumor movement. Results: Thirteen patients with 14 tumors were enrolled into the study. Substantial tumor movement was noted by either the extent of internal margins beyond each GTV or the movement of the centroid. Internal margins varied significantly according to the method of CT scanning for determination of GTV. Even for tumors in the same lobe of the lung, a wide range of internal margins and significant variation in the centroid movement in all directions (x, y, and z) were observed. The GTV of a single fast

  9. Changes in extracellular muscle volume affect heart rate and blood pressure responses to static exercise

    Science.gov (United States)

    Baum, K.; Essfeld, D.; Stegemann, J.

    To investigate the effect of μg-induced peripheral extracellular fluid reductions on heart rate and blood pressure during isometric exercise, six healthy male subjects performed three calf ergometer test with different extracellular volumes of working muscles. In all tests, body positions during exercise were identical (supine with the knee joint flexed to 900). After a pre-exercise period of 25 min, during which calf volumes were manipulated, subjects had to counteract an external force of 180 N for 5 min. During the pre-exercise period three different protocols were applied. Test A: Subjects rested in the exercise position; test B: Body position was the same as in A but calf volume was increased by venous congestion (cuffs inflated to 80 mm Hg); test C: Calf volumes were decreased by a negative hydrostatic pressure (calves about 40 cm above heart level with the subjects supine). To clamp the changed calf volumes in tests B and C, cuffs were inflated to 300 mm Hg 5 min before the onset of exercise. This occlusion was maintained until termination of exercise. Compared to tests A and B, the reduced volume of test C led to significant increases in heart rate and blood pressure during exercise. Oxygen uptake did not exceed resting levels in B and C until cuffs were deflated, indicating that exclusively calf muscles contributed to the neurogenic peripheral drive. It is concluded that changes in extracellular muscle volume have to be taken into account when comparing heart rate and blood pressure during lg- and μg- exercise.

  10. In vitro expansion of Lin{sup +} and Lin{sup −} mononuclear cells from human peripheral blood

    Energy Technology Data Exchange (ETDEWEB)

    Norhaiza, H. Siti; Zarina, Z. A. Intan; Hisham, Z. A. Shahrul [School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Selangor (Malaysia); Rohaya, M. A. W. [Department of Orthodontics, Faculty of Dentistry, Universiti Kebangsaan Malaysia, 50300, Kuala Lumpur (Malaysia)

    2013-11-27

    Haematopoietic stem cells (HSCs) are used in the therapy of blood disorders due to the ability of these cells to reconstitute haematopoietic lineage cells when transplanted into myeloablative recipients. However, substantial number of cells is required in order for the reconstitution to take place. Since HSCs present in low frequency, larger number of donor is required to accommodate the demand of transplantable HSCs. Therefore, in vitro expansion of HSCs will have profound impact on clinical purposes. The aim of this study was to expand lineage negative (Lin{sup −}) stem cells from human peripheral blood. Total peripheral blood mononuclear cells (PBMNCs) were fractionated from human blood by density gradient centrifugation. Subsequently, PBMNCs were subjected to magnetic assisted cell sorter (MACS) which depletes lineage positive (Lin{sup +}) mononuclear cells expressing lineage positive markers such as CD2, CD3, CD11b, CD14, CD15, CD16, CD19, CD56, CD123, and CD235a to obtained Lin{sup −} cell population. The ability of Lin{sup +} and Lin{sup −} to survive in vitro was explored by culturing both cell populations in complete medium consisting of Alpha-Minimal Essential Medium (AMEM) +10% (v/v) Newborn Calf Serum (NBCS)+ 2% (v/v) pen/strep. In another experiment, Lin{sup +} and Lin{sup −} were cultured with complete medium supplemented with 10ng/mL of the following growth factors: stem cell factor (SCF), interleukin (IL)-3, granulocyte-macrophage colony stimulating factor (GM-CSF), 2IU/mL of Erythropoietin (Epo) and 20ng/mL of IL-6. Three samples were monitored in static culture for 22 days. The expansion potential was assessed by the number of total viable cells, counted by trypan blue exclusion assay. It was found that Lin{sup +} mononuclear cells were not able to survive either in normal proliferation medium or proliferation medium supplemented with cytokines. Similarly, Lin{sup −} stem cells were not able to survive in proliferation medium however

  11. The measurement of peripheral blood volume reactions to tilt test by the electrical impedance technique after exercise in athletes

    International Nuclear Information System (INIS)

    We have investigated the distribution of peripheral blood volumes in different regions of the body in response to the tilt-test in endurance trained athletes after aerobic exercise. Distribution of peripheral blood volumes (ml/beat) simultaneously in six regions of the body (two legs, two hands, abdomen, neck and ECG) was assessed in response to the tilt-test using the impedance method (the impedance change rate (dZ/dT). Before and after exercise session cardiac stroke (CSV) and blood volumes in legs, arms and neck were higher in athletes both in lying and standing positions. Before exercise the increase of heart rate and the decrease of a neck blood volume in response to tilting was lower (p <0.05) but the decrease of leg blood volumes was higher (p<0.001) in athletes. The reactions in arms and abdomen blood volumes were similar. Also, the neck blood volumes as percentage of CSV (%/CSV) did not change in the control but increased in athletes (p <0.05) in response to the tilt test. After (10 min recovery) the aerobic bicycle exercise (mean HR = 156±8 beat/min, duration 30 min) blood volumes in neck and arms in response to the tilting were reduced equally, but abdomen (p<0.05) and leg blood volumes (p <0.001) were lowered more significantly in athletes. The neck blood flow (%/CSV) did not change in athletes but decreased in control (p<0.01), which was offset by higher tachycardia in response to tilt-test in controls after exercise. The data demonstrate greater orthostatic tolerance in athletes both before and after exercise during fatigue which is due to effective distribution of blood flows aimed at maintaining cerebral blood flow.

  12. Postoperative volume balance

    DEFF Research Database (Denmark)

    Frost, H; Mortensen, C.R.; Secher, N H;

    2016-01-01

    In healthy humans, stroke volume (SV) and cardiac output (CO) do not increase with expansion of the central blood volume by head-down tilt or administration of fluid. Here, we exposed 85 patients to Trendelenburg's position about one hour after surgery while cardiovascular variables were determined...

  13. Analytical method of PBDES and PCBS from small volume human blood

    Energy Technology Data Exchange (ETDEWEB)

    Fujimine, Y.; Koizumi, A. [Kyoto Univ. (Japan); Mochizuki, A.; Hirai, T. [Otsuka Pharmaceutical, Tokushima (Japan)

    2004-09-15

    In order to conduct the epidemiological survey for children and old peoples, it is necessary to develop/improve the analytical method with which to conduct the analysis in smaller volume of blood samples because the blood volume from these subjects are normally allowed to take less than 5mL. For these purposes, we developed the Small Volume method (SV-method) using HRGC/HRMS for the PCBs and PBDEs analysis. The SV method for PCB can start the analysis only with 1.0 mL of whole blood and that for PBDE with 1.5 mL of whole blood, respectively; these methods showed the ultra high sensitivity. However the SV-method can not determine all isomer of PCBs and PBDEs but only predominant isomers of those chemicals. In the Healthy volunteers examination, the SV-PCB determined 13 isomers and the SV-PBDE method determined 4 isomers, respectively. By the way, SV-PCB and SV-PBDE method determined almost all levels in the sample; SV-PCB is 75% as compared with sum of all PCB isomers level, SV-PBDE is 82% as compared with sum of all PBDE isomers level. In summary, SV-method using HRGC/HRMS can determine approximate and predominant isomers levels of PCBs and PBDEs, making it possible to evaluate the human exposure to these chemicals. In this paper, the method of SV-PCB and SV-PBDE were described with precision date.

  14. Portal blood flow volume measurement in schistosomal patients: evaluation of Doppler ultrasonography reproducibility

    International Nuclear Information System (INIS)

    Objective: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. Materials and methods: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearson's correlation coefficient. Results: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearson's correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). Conclusion: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement. (author)

  15. Human cerebral blood volume measurements using dynamic contrast enhancement in comparison to dynamic susceptibility contrast MRI

    International Nuclear Information System (INIS)

    Cerebral blood volume (CBV) is an important parameter for the assessment of brain tumors, usually obtained using dynamic susceptibility contrast (DSC) MRI. However, this method often suffers from low spatial resolution and high sensitivity to susceptibility artifacts and usually does not take into account the effect of tissue permeability. The plasma volume (vp) can also be extracted from dynamic contrast enhancement (DCE) MRI. The aim of this study was to investigate whether DCE can be used for the measurement of cerebral blood volume in place of DSC for the assessment of patients with brain tumors. Twenty-eight subjects (17 healthy subjects and 11 patients with glioblastoma) were scanned using DCE and DSC. vp and CBV values were measured and compared in different brain components in healthy subjects and in the tumor area in patients. Significant high correlations were detected between vp and CBV in healthy subjects in the different brain components; white matter, gray matter, and arteries, correlating with the known increased tissue vascularity, and within the tumor area in patients. This work proposes the use of DCE as an alternative method to DSC for the assessment of blood volume, given the advantages of its higher spatial resolution, its lower sensitivity to susceptibility artifacts, and its ability to provide additional information regarding tissue permeability. (orig.)

  16. Variations in gastric compliance induced by acute blood volume changes in anesthetized rats

    Directory of Open Access Journals (Sweden)

    Graça J.R.V.

    2002-01-01

    Full Text Available The impact of acute volume imbalances on gastric volume (GV was studied in anesthetized rats (250-300 g. After cervical and femoral vessel cannulation, a balloon catheter was positioned in the proximal stomach. The opposite end of the catheter was connected to a barostat with an electronic sensor coupled to a plethysmometer. A standard ionic solution was used to fill the balloon (about 3.0 ml and the communicating vessel system, and to raise the reservoir liquid level 4 cm above the animals' xiphoid appendix. Due to constant barostat pressure, GV values were considered to represent the gastric compliance index. All animals were monitored for 90 min. After a basal interval, they were randomly assigned to normovolemic, hypervolemic, hypovolemic or restored protocols. Data were compared by ANOVA followed by Bonferroni's test. Mean arterial pressure (MAP, central venous pressure (CVP and GV values did not change in normovolemic animals (N = 5. Hypervolemic animals (N = 12 were transfused at 0.5 ml/min with a suspension of red blood cells in Ringer-lactate solution with albumin (12.5 ml/kg, which reduced GV values by 11.3% (P0.05. MAP and CVP values increased (P<0.05 after hypervolemia but decreased (P<0.05 with hypovolemia. In conclusion, blood volume level modulates gastric compliance, turning the stomach into an adjustable reservoir, which could be part of the homeostatic process to balance blood volume.

  17. Human cerebral blood volume measurements using dynamic contrast enhancement in comparison to dynamic susceptibility contrast MRI

    Energy Technology Data Exchange (ETDEWEB)

    Artzi, Moran [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Liberman, Gilad; Vitinshtein, Faina; Aizenstein, Orna [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Nadav, Guy [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Faculty of Engineering, Tel Aviv (Israel); Blumenthal, Deborah T.; Bokstein, Felix [Tel Aviv Sourasky Medical Center, Neuro-Oncology Service, Tel Aviv (Israel); Bashat, Dafna Ben [Tel Aviv Sourasky Medical Center, Functional Brain Center, The Wohl Institute for Advanced Imaging, Tel Aviv (Israel); Tel Aviv University, Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv (Israel)

    2015-07-15

    Cerebral blood volume (CBV) is an important parameter for the assessment of brain tumors, usually obtained using dynamic susceptibility contrast (DSC) MRI. However, this method often suffers from low spatial resolution and high sensitivity to susceptibility artifacts and usually does not take into account the effect of tissue permeability. The plasma volume (v{sub p}) can also be extracted from dynamic contrast enhancement (DCE) MRI. The aim of this study was to investigate whether DCE can be used for the measurement of cerebral blood volume in place of DSC for the assessment of patients with brain tumors. Twenty-eight subjects (17 healthy subjects and 11 patients with glioblastoma) were scanned using DCE and DSC. v{sub p} and CBV values were measured and compared in different brain components in healthy subjects and in the tumor area in patients. Significant high correlations were detected between v{sub p} and CBV in healthy subjects in the different brain components; white matter, gray matter, and arteries, correlating with the known increased tissue vascularity, and within the tumor area in patients. This work proposes the use of DCE as an alternative method to DSC for the assessment of blood volume, given the advantages of its higher spatial resolution, its lower sensitivity to susceptibility artifacts, and its ability to provide additional information regarding tissue permeability. (orig.)

  18. Decreased right heart blood volume determined by magnetic resonance imaging: evidence of central underfilling in cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Søndergaard, L; Møgelvang, J;

    1995-01-01

    ), and end-systolic volumes (RVSV and LVSV) determined by magnetic resonance imaging (MRI). RVDV (122 vs. control 166 mL, P < .02), RVSV (41 vs. 80 mL, P < .02) and right atrial volume (47 vs. 64 mL, P < .05) were significantly reduced in the patients. In contrast, LVDV (134 vs. 129 mL, NS), LVSV (54 vs...... the cardiac output (CO) multiplied by the central circulation time, was significantly decreased (1.47 vs. 1.81 L, P < .05). The noncentral blood volume (4.43 vs. 3.64 L, P < .02), plasma volume (4.05 vs. 3.27 L, P < .02), and CO (7.11 vs. control 5.22 L/min, P < .01) were significantly increased in...

  19. Errors of the backextrapolation method in determination of the blood volume

    Science.gov (United States)

    Schröder, T.; Rösler, U.; Frerichs, I.; Hahn, G.; Ennker, J.; Hellige, G.

    1999-01-01

    Backextrapolation is an empirical method to calculate the central volume of distribution (for example the blood volume). It is based on the compartment model, which says that after an injection the substance is distributed instantaneously in the central volume with no time delay. The occurrence of recirculation is not taken into account. The change of concentration with time of indocyanine green (ICG) was observed in an in vitro model, in which the volume was recirculating in 60 s and the clearance of the ICG could be varied. It was found that the higher the elimination of ICG, the higher was the error of the backextrapolation method. The theoretical consideration of Schröder et al ( Biomed. Tech. 42 (1997) 7-11) was proved. If the injected substance is eliminated somewhere in the body (i.e. not by radioactive decay), the backextrapolation method produces large errors.

  20. Decreased right heart blood volume determined by magnetic resonance imaging: evidence of central underfilling in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Søndergaard, Lise; Møgelvang, J; Henriksen, O; Henriksen, Jens Henrik

    1995-01-01

    ), and end-systolic volumes (RVSV and LVSV) determined by magnetic resonance imaging (MRI). RVDV (122 vs. control 166 mL, P < .02), RVSV (41 vs. 80 mL, P < .02) and right atrial volume (47 vs. 64 mL, P < .05) were significantly reduced in the patients. In contrast, LVDV (134 vs. 129 mL, NS), LVSV (54 vs...... the cardiac output (CO) multiplied by the central circulation time, was significantly decreased (1.47 vs. 1.81 L, P <.05). The noncentral blood volume (4.43 vs. 3.64 L, P < .02), plasma volume (4.05 vs. 3.27 L, P < .02), and CO (7.11 vs. control 5.22 L/min, P < .01) were significantly increased in the...

  1. Doppler sonography of diabetic feet: Quantitative analysis of blood flow volume

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Young Lan; Kim, Ho Chul; Choi, Chul Soon; Yoon, Dae Young; Han, Dae Hee; Moon, Jeung Hee; Bae, Sang Hoon [Hallym University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    To analyze Doppler sonographic findings of diabetic feet by estimating the quantitative blood flow volume and by analyzing waveform on Doppler. Doppler sonography was performed in thirty four patients (10 diabetic patients with foot ulceration, 14 diabetic patients without ulceration and 10 normal patients as the normal control group) to measure the flow volume of the arteries of the lower extremities (posterior and anterior tibial arteries, and distal femoral artery. Analysis of doppler waveforms was also done to evaluate the nature of the changed blood flow volume of diabetic patients, and the waveforms were classified into triphasic, biphasic-1, biphasic-2 and monophasic patterns. Flow volume of arteries in diabetic patients with foot ulceration was increased witha statistical significance when compared to that of diabetes patients without foot ulceration of that of normal control group (P<0.05). Analysis of Doppler waveform revealed that the frequency of biphasic-2 pattern was significantly higher in diabetic patients than in normal control group(p<0.05). Doppler sonography in diabetic feet showed increased flow volume and biphasic Doppler waveform, and these findings suggest neuropathy rather than ischemic changes in diabetic feet.

  2. Application for approval of the Cold Lake Expansion Project: volume 1: project description

    International Nuclear Information System (INIS)

    Imperial Oil Resources Limited has applied for approval from both the Alberta Energy and Utilities Board and the Albert Environmental Protection Branch for approvals to expand bitumen recovery operations at Cold Lake, Alberta. The proposed project will consist of: (1) a new three-phase oil field development called Mahkeses which will recover 46 million cubic metres of bitumen at a production rate of 4,800 cubic metres per day, (2) a 220 megawatt electrical power cogeneration facility at the Mahkeses central plant, and (3) additional development to maintain and optimize bitumen steam production at the company's existing Maskwa and Mahihkan operation areas at Cold Lake. Cyclic steam stimulation will be used to recover the bitumen. The expansion will involve drilling new wells, construction of pipelines and multiwell pads. Production will be processed at the plants before the bitumen is mixed with diluent to reduce its viscosity. The bitumen will be transported to markets through pipeline systems originating in Cold Lake. Approximately 45 per cent of the electricity generated from the electrical power cogeneration facility will be used on site. The remainder will be available for sale to the Alberta Power Pool. 18 refs., 32 tabs., 55 figs

  3. Patient-specific coronary artery blood flow simulation using myocardial volume partitioning

    Science.gov (United States)

    Kim, Kyung Hwan; Kang, Dongwoo; Kang, Nahyup; Kim, Ji-Yeon; Lee, Hyong-Euk; Kim, James D. K.

    2013-03-01

    Using computational simulation, we can analyze cardiovascular disease in non-invasive and quantitative manners. More specifically, computational modeling and simulation technology has enabled us to analyze functional aspect such as blood flow, as well as anatomical aspect such as stenosis, from medical images without invasive measurements. Note that the simplest ways to perform blood flow simulation is to apply patient-specific coronary anatomy with other average-valued properties; in this case, however, such conditions cannot fully reflect accurate physiological properties of patients. To resolve this limitation, we present a new patient-specific coronary blood flow simulation method by myocardial volume partitioning considering artery/myocardium structural correspondence. We focus on that blood supply is closely related to the mass of each myocardial segment corresponding to the artery. Therefore, we applied this concept for setting-up simulation conditions in the way to consider many patient-specific features as possible from medical image: First, we segmented coronary arteries and myocardium separately from cardiac CT; then the myocardium is partitioned into multiple regions based on coronary vasculature. The myocardial mass and required blood mass for each artery are estimated by converting myocardial volume fraction. Finally, the required blood mass is used as boundary conditions for each artery outlet, with given average aortic blood flow rate and pressure. To show effectiveness of the proposed method, fractional flow reserve (FFR) by simulation using CT image has been compared with invasive FFR measurement of real patient data, and as a result, 77% of accuracy has been obtained.

  4. 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

    from whom pulmonary capillary wedge pressure (PCWP), central venous pressure and SV (via thermodilution) were obtained while central blood volume was reduced via lower-body negative pressure (LBNP) during normothermia, whole-body heating (increase in blood temperature 1 degrees C), and during whole......During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading of...... in the SV to PCWP ratio during LBNP was comparable to that observed during normothermia (4.8 +/- 2.3 ml mmHg(1); P = 0.78). These data support the hypothesis that a Frank-Starling mechanism contributes to compromised blood pressure control during simulated haemorrhage in heat-stressed individuals...

  5. Constitutive modeling for rubber-toughened polymers with evolutional anisotropy and volume expansion

    International Nuclear Information System (INIS)

    A constitutive model for rubber-toughened polymer blends is developed. In most cases, rubber particles contained in a blend can be idealized as voids, because the microscopic cavitation and debonding of rubber particles occurs at a rather early stage of deformation. Under this approximation, a rubber-toughened polymer (polycarbonate—20 vol%SEBS rubber blend) is considered as a porous material. In the present constitutive model, a geometric anisotropy due to changes in void shape during deformation is taken into account. Furthermore, plastic potential and yield condition are modeled as distinct functions in order to accurately reproduce the macroscopic volume change behavior. The values of material parameters are determined through a series of precise experimental studies. It is shown that the proposed constitutive model exhibits a sufficient predictability for the mechanical response of rubber-toughened polymers for engineering applications

  6. 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.

  7. Reduction of pulmonary capillary blood volume in patients with severe unexplained pulmonary hypertension.

    OpenAIRE

    Borland, C.; Cox, Y.; Higenbottam, T

    1996-01-01

    BACKGROUND: Unexplained or primary pulmonary hypertension results in an obliteration and obstruction of resistance pulmonary arteries. In these patients gas exchange is impaired and the measurement of gas transfer for carbon monoxide is usually reduced. This has been thought to represent a reduction in pulmonary alveolar capillary blood volume (Vc). A single breath test, measuring simultaneously the uptake of both nitric oxide (NO) and carbon monoxide (CO), provides a simple and practical mea...

  8. Assessing Pulmonary Perfusion in Emphysema Automated Quantification of Perfused Blood Volume in Dual-Energy CTPA

    OpenAIRE

    Meinel, Felix G.; Graef, Anita; Thieme, Sven F.; Bamberg, Fabian; Schwarz, Florian; Sommer, Wieland; Helck, Andreas D.; Neurohr, Claus; Reiser, Maximilian F.; Johnson, Thorsten R. C.

    2013-01-01

    Objectives: The objective of this study was to determine whether automated quantification of lung perfused blood volume (PBV) in dual-energy computed tomographic pulmonary angiography (DE-CTPA) can be used to assess the severity and regional distribution of pulmonary hypoperfusion in emphysema. Materials and Methods: We retrospectively analyzed 40 consecutive patients (mean age, 67 13] years) with pulmonary emphysema, who have no cardiopulmonary comorbidities, and a DE-CTPA negative for pulmo...

  9. Measurement of brain perfusion, blood volume, and blood-brain barrier permeability, using dynamic contrast-enhanced T(1)-weighted MRI at 3 tesla

    DEFF Research Database (Denmark)

    Larsson, Henrik B W; Courivaud, Frédéric; Rostrup, Egill;

    2009-01-01

    Assessment of vascular properties is essential to diagnosis and follow-up and basic understanding of pathogenesis in brain tumors. In this study, a procedure is presented that allows concurrent estimation of cerebral perfusion, blood volume, and blood-brain permeability from dynamic T(1)-weighted...

  10. Minimal volume regulation after shrinkage of red blood cells from five species of reptiles

    DEFF Research Database (Denmark)

    Kristensen, Karina; Berenbrink, Michael; Koldkjær, Pia;

    2008-01-01

    Red blood cells (RBCs) from most vertebrates restore volume upon hypertonic shrinkage and the mechanisms underlying this regulatory volume increase (RVI) have been studied extensively in these cells. Despite the phylogenetically interesting position of reptiles, very little is known about their red...... cell function. The present study demonstrates that oxygenated RBCs in all major groups of reptiles exhibit no or a very reduced RVI upon ~ 25% calculated hyperosmotic shrinkage. Thus, RBCs from the snakes Crotalus durissus and Python regius, the turtle Trachemys scripta and the alligator Alligator...... mississippiensis showed no statistically significant RVI within 120 min after shrinkage, while the lizard Tupinambis merianae showed 22% volume recovery after 120 min. Amiloride (10- 4 M) and bumetanide (10- 5 M) had no effect on the RVI in T. merianae, indicating no involvement of the Na+/H+ exchanger (NHE) or...

  11. Age-related changes in regional cerebral blood flow and brain volume in healthy subjects

    International Nuclear Information System (INIS)

    Using the xenon-133 inhalation method, we studied the age-related decline in regional cerebral blood flow, calculated as the initial slope index (ISI), in neurologically normal subjects without any risk factors for cerebral arteriosclerosis (154 men and 123 women), ranging in age from 19 to 88 years. The decline in the ISI was rapid in younger age groups and gradual in older age groups. The ISI was higher in women than in men older than 40 years. Using computed tomography, we studied the age-related decline in brain volume index (BVI; 100% X brain volume/cranial cavity volume) in neurologically normal subjects without any risk factors for cerebral arteriosclerosis (92 men and 49 women), ranging in age from 37 to 86 years. The decline in the BVI was gradual in younger age groups and rapid in older age groups. The BVI was higher in women than in men older than 60 years

  12. Study of the spatial distribution of the absorbed dose in blood volumes irradiated using a teletherapy unit

    International Nuclear Information System (INIS)

    Blood irradiation can be performed using a dedicated blood irradiator or a teletherapy unit. A thermal device providing appropriate storage conditions during blood components irradiation with a teletherapy unit has been recently proposed. However, the most appropriated volume of the thermal device was not indicated. The goal of this study was to indicate the most appropriated blood volume for irradiation using a teletherapy unit in order to minimize both the dose heterogeneity in the volume and the blood irradiation time using these equipments. Theoretical and experimental methods were used to study the dose distribution in the blood volume irradiated using a linear accelerator and a cobalt-60 therapy machine. The calculation of absorbed doses in the middle plane of cylindrical acrylic volumes was accomplished by a treatment planning system. Experimentally, we also used cylindrical acrylic phantoms and thermoluminescent dosimeters to confirm the calculated doses. The data obtained were represented by isodose curves. We observed that an irradiation volume should have a height of 28 cm and a diameter of 28 cm and a height of 35 cm and a diameter of 35 cm, when the irradiation is to be performed by a linear accelerator and a cobalt-60 teletherapy unit, respectively. Calculated values of relative doses varied from 93% to 100% in the smaller volume, and from 66% to 100% in the largest one. A difference of 5.0%, approximately, was observed between calculated and experimental data. The size of these volumes permits the irradiation of blood bags in only one bath without compromising the homogeneity of the absorbed dose over the irradiated volume. Thus, these irradiation volumes can be recommend to minimize the irradiation time when a teletherapy unit is used to irradiate blood.

  13. Ionic events during the volume response of human peripheral blood lymphocytes to hypotonic media. I. Distinctions between volume- activated Cl- and K+ conductance pathways

    OpenAIRE

    1984-01-01

    Human peripheral blood lymphocytes (PBL), when placed into hypotonic media, first swell and then shrink back to their original volumes because of a rapid KCl leakage via volume-activated K+ and anion permeation pathways. By using gramicidin, a cation channel-forming ionophore, cation transport through the cell membrane can be shunted so that the salt fluxes and thus the volume changes are limited by the rate of the net anion movements. The "gramicidin method," supplemented with direct measure...

  14. Densities, Excess Molar Volumes, and Thermal Expansion Coefficients of Aqueous Aminoethylethanolamine Solutions at Temperatures from 283.15 to 343.15 K.

    Science.gov (United States)

    Stec, Marcin; Tatarczuk, Adam; Spiewak, Dariusz; Wilk, Andrzej

    2014-01-01

    The densities of aqueous mixtures of aminoethylethanolamine (CAS #000111-41-1) were measured over the entire compositional range at temperatures of 283.15-343.15 K. The results of these measurements were used to calculate excess molar volumes and isobaric thermal expansion coefficients, and partial molar and apparent molar volumes and excess isobaric thermal expansion coefficients were subsequently derived. The excess molar volumes were correlated as a function of the mole fraction using the Redlich-Kister equation. Temperature dependences of the Redlich-Kister coefficients are also presented. The partial molar volumes at infinite dilution of AEEA in water were determined using two different methods. In addition, the solution density was correlated using a Joubian-Acree model. Aqueous solutions of AEEA exhibit similar properties to the aqueous solutions of other alkanolamines (like monoethanolamine) used in acid gas sweetening. PMID:24899753

  15. 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; Secher, N H; Crandall, C G

    During reductions in central blood volume while heat stressed, a greater decrease in stroke volume (SV) for a similar decrease in ventricular filling pressure, compared to normothermia, suggests that the heart is operating on a steeper portion of a Frank-Starling curve. If so, volume loading of...... heat-stressed individuals would shift the operating point to a flatter portion of the heat stress Frank-Starling curve thereby attenuating the reduction in SV during subsequent decreases in central blood volume. To investigate this hypothesis, right heart catheterization was performed in eight males...... in the SV to PCWP ratio during LBNP was comparable to that observed during normothermia (4.8 +/- 2.3 ml mmHg(1); P = 0.78). These data support the hypothesis that a Frank-Starling mechanism contributes to compromised blood pressure control during simulated haemorrhage in heat-stressed individuals...

  16. In vivo volume and hemoglobin dynamics of human red blood cells.

    Directory of Open Access Journals (Sweden)

    Roy Malka

    2014-10-01

    Full Text Available Human red blood cells (RBCs lose ∼30% of their volume and ∼20% of their hemoglobin (Hb content during their ∼100-day lifespan in the bloodstream. These observations are well-documented, but the mechanisms for these volume and hemoglobin loss events are not clear. RBCs shed hemoglobin-containing vesicles during their life in the circulation, and this process is thought to dominate the changes in the RBC physical characteristics occurring during maturation. We combine theory with single-cell measurements to investigate the impact of vesiculation on the reduction in volume, Hb mass, and membrane. We show that vesicle shedding alone is sufficient to explain membrane losses but not volume or Hb losses. We use dry mass measurements of human RBCs to validate the models and to propose that additional unknown mechanisms control volume and Hb reduction and are responsible for ∼90% of the observed reduction. RBC population characteristics are used in the clinic to monitor and diagnose a wide range of conditions including malnutrition, inflammation, and cancer. Quantitative characterization of cellular maturation processes may help in the early detection of clinical conditions where maturation patterns are altered.

  17. Variation of Red Blood Cell Distribution Width and Mean Platelet Volume after Moderate Endurance Exercise

    Directory of Open Access Journals (Sweden)

    Giuseppe Lippi

    2014-01-01

    Full Text Available Although physical exercise strongly influences several laboratory parameters, data about the hematological changes after medium distance running are scarce. We studied 31 middle-trained athletes (mean training regimen 217±32 min/week who performed a 21.1 km, half-marathon run. Blood samples were collected before the run, at the end, and 3 and 20 hours thereafter. The complete blood count was performed on Advia 2120 and included red blood cell (RBC, reticulocyte, and platelet counts; hemoglobin; mean corpuscular volume (MCV; mean corpuscular hemoglobin (MCH; reticulocyte haemoglobin content (Ret CHR; RBC distribution width (RDW, mean platelet volume (MPV. No significant variations were observed for MCH and Ret CHR. The RBC, reticulocyte, and hemoglobin values modestly decreased after the run. The MCV significantly increased at the end of running but returned to baseline 3 hours thereafter. The RDW constantly increased, reaching a peak 20 hours after the run. The platelet count and MPV both increased after the run and returned to baseline 3 hours thereafter. These results may have implications for definition of reference ranges and antidoping testing, and may also contribute to explaining the relationship between endurance exercise and mortality, since previous studies reported that RDW and MPV may be significantly associated with cardiovascular disease.

  18. Variation of red blood cell distribution width and mean platelet volume after moderate endurance exercise.

    Science.gov (United States)

    Lippi, Giuseppe; Salvagno, Gian Luca; Danese, Elisa; Tarperi, Cantor; Guidi, Gian Cesare; Schena, Federico

    2014-01-01

    Although physical exercise strongly influences several laboratory parameters, data about the hematological changes after medium distance running are scarce. We studied 31 middle-trained athletes (mean training regimen 217 ± 32 min/week) who performed a 21.1 km, half-marathon run. Blood samples were collected before the run, at the end, and 3 and 20 hours thereafter. The complete blood count was performed on Advia 2120 and included red blood cell (RBC), reticulocyte, and platelet counts; hemoglobin; mean corpuscular volume (MCV); mean corpuscular hemoglobin (MCH); reticulocyte haemoglobin content (Ret CHR); RBC distribution width (RDW), mean platelet volume (MPV). No significant variations were observed for MCH and Ret CHR. The RBC, reticulocyte, and hemoglobin values modestly decreased after the run. The MCV significantly increased at the end of running but returned to baseline 3 hours thereafter. The RDW constantly increased, reaching a peak 20 hours after the run. The platelet count and MPV both increased after the run and returned to baseline 3 hours thereafter. These results may have implications for definition of reference ranges and antidoping testing, and may also contribute to explaining the relationship between endurance exercise and mortality, since previous studies reported that RDW and MPV may be significantly associated with cardiovascular disease. PMID:25197280

  19. Circulating atrial natriuretic peptide (ANP) and central blood volume (CBV) in cirrhosis

    DEFF Research Database (Denmark)

    Schütten, H J; Henriksen, Jens Henrik Sahl; Bendtsen, F; Warberg, J

    1986-01-01

    ). Arterial plasma concentration of ANP in supine patients was (mean +/- SEM) 33 +/- 4 vs 41 +/- 10 pg/ml (9.9 +/- 1.2 vs 12.3 +/- 3.0 fmol/l) in controls (n.s.), and there was a weak direct correlation with right atrial pressure (r = 0.36, P = 0.05). There was no relationship with the presence of ascites or...... diuretic treatment. Central blood volume (CBV, i.e. the blood volume in the heart cavities, lungs, and aorta), determined from the mean transit time of 125I-labelled of 125I-labelled albumin and cardiac output, was significantly reduced in cirrhotics compared to controls (1.45 +/- 0.12 vs. 1.83 +/- 0.10 l......, P less than 0.02) and inversely correlated with portal pressure (r = 0.42, P less than 0.05), whereas total plasma volume was somewhat increased (3.51 +/- 0.2 vs. 3.19 +/- 0.2, 0.05 less than P less than 0.1). A high arterio-venous extraction of ANP was found in the splanchnic system (extraction...

  20. Greater Volume of Acute Normovolemic Hemodilution May Aid in Reducing Blood Transfusions After Cardiac Surgery

    Science.gov (United States)

    Goldberg, Joshua; Paugh, Paugh; Dickinson, Timothy A.; Fuller, John; Paone, Gaetano; Theurer, Patty F.; Shann, Kenneth G.; Sundt, Thoralf M.; Prager, Richard L.; Likosky, Donald S.

    2016-01-01

    Background Perioperative red blood cell transfusions (RBC) are associated with increased morbidity and mortality after cardiac surgery. Acute normovolemic hemodilution (ANH) is recommended to reduce perioperative transfusions; however, supporting data are limited and conflicting. We describe the relationship between ANH and RBC transfusions after cardiac surgery using a multi-center registry. Methods We analyzed 13,534 patients undergoing cardiac surgery between 2010 and 2014 at any of the 26 hospitals participating in a prospective cardiovascular perfusion database. The volume of ANH (no ANH, HCT, and center. Results ANH was used in 17% of the patients. ANH was associated with a reduction in RBC transfusions (RRadj 0.74, p <0.001). Patients having ≥800mL of ANH had the most profound reduction in RBC transfusions (RRadj 0.57, p<0.001). Platelet and plasma transfusions were also significantly lower with ANH. The ANH population had superior postoperative morbidity and mortality compared to the no ANH population. Conclusions There is a significant association between ANH and reduced perioperative RBC transfusion in cardiac surgery. Transfusion reduction is most profound with larger volumes of ANH. Our findings suggest the volume of ANH, rather than just its use, may be an important feature of a center’s blood conservation strategy. PMID:26206721

  1. Vascular surgical society of great britain and ireland: immunoglobulin A antibodies against chlamydia pneumoniae are associated with expansion of small abdominal aortic aneurysms and declining ankle blood pressure

    DEFF Research Database (Denmark)

    Lindholt, Jes S.; Vammen; Henneberg;

    1999-01-01

    or greater, were significant independent predictors of AAA expansion adjusted for age, smoking, initial AAA size, steroid treatment, diastolic blood pressure, pulmonary function and other plasma factors. The ankle blood pressure index (ABI) of the IgA-seropositive men decreased 11 per cent, while the...... ABI decreased by 5 per cent among IgA-seronegative men (P < 0.05). The significant difference persisted after adjusting for age, smoking, initial systolic ankle blood pressure, initial brachial systolic or diastolic blood pressure, but disappeared after adjusting for low-density lipoprotein (LDL....... Some 139 men (aged 65-73 years) with a 3.0-4.9-cm AAA were followed prospectively for 1-3 (mean 2.7) years. Initially, an interview and examination was performed, and blood samples were taken. RESULTS: Some 62 per cent (53-71 per cent) had an immunoglobulin (Ig) A level of 40 or more, or an IgG level...

  2. Influence of anodization parameters on the volume expansion of anodic aluminum oxide formed in mixed solution of phosphoric and oxalic acids

    Science.gov (United States)

    Kao, Tzung-Ta; Chang, Yao-Chung

    2014-01-01

    The growth of anodic alumina oxide was conducted in the mixed solution of phosphoric and oxalic acids. The influence of anodizing voltage, electrolyte temperature, and concentration of phosphoric and oxalic acids on the volume expansion of anodic aluminum oxide has been investigated. Either anodizing parameter is chosen to its full extent of range that allows the anodization process to be conducted without electric breakdown and to explore the highest possible volume expansion factor. The volume expansion factors were found to vary between 1.25 and 1.9 depending on the anodizing parameters. The variation is explained in connection with electric field, ion transport number, temperature effect, concentration, and activity of acids. The formation of anodic porous alumina at anodizing voltage 160 V in 1.1 M phosphoric acid mixed with 0.14 M oxalic acid at 2 °C showed the peak volume expansion factor of 1.9 and the corresponding moderate growth rate of 168 nm/min.

  3. Rapid multi-wavelength optical assessment of circulating blood volume without a priori data

    Science.gov (United States)

    Loginova, Ekaterina V.; Zhidkova, Tatyana V.; Proskurnin, Mikhail A.; Zharov, Vladimir P.

    2016-03-01

    The measurement of circulating blood volume (CBV) is crucial in various medical conditions including surgery, iatrogenic problems, rapid fluid administration, transfusion of red blood cells, or trauma with extensive blood loss including battlefield injuries and other emergencies. Currently, available commercial techniques are invasive and time-consuming for trauma situations. Recently, we have proposed high-speed multi-wavelength photoacoustic/photothermal (PA/PT) flow cytometry for in vivo CBV assessment with multiple dyes as PA contrast agents (labels). As the first step, we have characterized the capability of this technique to monitor the clearance of three dyes (indocyanine green, methylene blue, and trypan blue) in an animal model. However, there are strong demands on improvements in PA/PT flow cytometry. As additional verification of our proof-of-concept of this technique, we performed optical photometric CBV measurements in vitro. Three label dyes—methylene blue, crystal violet and, partially, brilliant green—were selected for simultaneous photometric determination of the components of their two-dye mixtures in the circulating blood in vitro without any extra data (like hemoglobin absorption) known a priori. The tests of single dyes and their mixtures in a flow system simulating a blood transfusion system showed a negligible difference between the sensitivities of the determination of these dyes under batch and flow conditions. For individual dyes, the limits of detection of 3×10-6 M‒3×10-6 M in blood were achieved, which provided their continuous determination at a level of 10-5 M for the CBV assessment without a priori data on the matrix. The CBV assessment with errors no higher than 4% were obtained, and the possibility to apply the developed procedure for optical photometric (flow cytometry) with laser sources was shown.

  4. Ischaemic cerebral infarction combined determination of regional cerebral blood flow and volume via SPECT

    International Nuclear Information System (INIS)

    A combined measurement of regional cerebral blood flow (r CBF) and volume (r CBV) by SPECT was performed in 15 patients with ischaemic cerebral infarction. For measurement of r CBF 99mTc-HMPAO was used, and for r CBV 99mTc-labelled red blood cells. Patients with acute or subacute cerebral infarction (n=10) showed elevation of r CBV whereas r CBF was either reduced or elevated. Patients with chronic cerebral infarction (n=5) showed reduction of both r CBF and R CBV. The combined measurement of both r CBF and r CBV by SPECT allows imaging and semiquantitative evaluation of haemodynamic changes in ischaemic cerebral infarction at various stages. The resulting data may be helpful in describing the pathophysiologic compensatory mechanisms. (orig.)

  5. Optimal velocity encoding during measurement of cerebral blood flow volume using phase-contrast magnetic resonance angiography

    Institute of Scientific and Technical Information of China (English)

    Gang Guo; Yonggui Yang; Weiqun Yang

    2011-01-01

    This study investigated the effect of velocity encoding on measurement of brain blood flow and blood volume of inflow and outflow using phase-contrast magnetic resonance angiography. A single two-dimensional phase-contrast magnetic resonance angiography slice was applied perpendicular to the internal carotid artery and the vertebral artery at C2 level. For each subject, the velocity encoding was set from 30 to 90 cm/s with an interval of 10 cm/s for a total of seven settings. Various velocity encodings greatly affected blood flow volume, maximal blood flow velocity and mean blood flow velocity in the internal carotid artery, but did not significantly affect vertebral arteries and jugular veins. When velocity encoding was 60-80 cm/s, the inflow blood volume was 655 ± 118 mL/min, and the outflow volume was 506 ± 186 mL/min. The ratio of outflow/inflow was steady at 0.78-0.83, and there was no aliasing in any of the images. These findings suggest that velocity encodings of 60-80 cm/s should be selected during measurement of cerebral blood flow volume using phase-contrast magnetic resonance angiography.

  6. Scintigraphic method for evaluating reductions in local blood volumes in human extremities

    DEFF Research Database (Denmark)

    Blønd, L; Madsen, Jan Lysgård

    2000-01-01

    experiment. Evaluation of one versus two scintigraphic projections, trials for assessment of the reproducibility, a comparison of the scintigraphic method with a water-plethysmographic method and registration of the fractional reduction in blood volume caused by exsanguination as a result of simple elevation...... were carried out. No significant differences between results obtained by the use of one or two scintigraphic projections were found. The between-subject coefficient of variation was 14% in the lower limb experiment and 11% in the upper limb experiment. The within-subject coefficient of variation was 6...

  7. Effects of thermal stress and exercise on blood volume in humans

    Science.gov (United States)

    Harrison, M. H.

    1985-01-01

    The available experimental data base on the effects of exercise, posture and the environment (heat) on the blood volume, composition and concentration in humans is surveyed in depth to synthesize supportable conclusions. A large disparity is noted in the effective controls which were initiated in previous experimental conditions, resulting in contradictory findings regarding, e.g., hemoconcentrations and hemodilution in response to exercise. Comparisons between the results of exercise and of supine, seated and upright subjects has underscored the importance of gravity in hemoconcentration, particularly in the legs, and the generation of aldotestosterone. Hemoconcentration has been confirmed to increase with exercise in a seated or supine position. Exercise in a heated environment transfers cardiac output from core areas and reduces filtration efficiencies. Also, plasma volume increases, an action which cannot yet be associated with crystalloidal or colloidal influences on the osmotic behavior of cell walls.

  8. Model estimation of cerebral hemodynamics between blood flow and volume changes: a data-based modelling approach

    OpenAIRE

    Wei, H L; Zheng, Y; Pan, Y.; Coca, D.; Li, L M; Mayhew, J.E.W.; S. A. Billings

    2008-01-01

    It is well known that there is a dynamic relationship between cerebral blood flow (CBF) and cerebral blood volume (CBV). With increasing applications of functional magnetic resonance imaging (fMRI), where the blood oxygen level dependent (BOLD) signals are recorded, the understanding and accurate modelling of the hemodynamic relationship between CBF and CBV becomes increasingly important. This study presents an empirical and data-based modelling framework for model identification from CBF and...

  9. Clinical significance of regional cerebral blood volume and flow-to-volume ratio in ischemic cerebrovascular disease measeured by SPECT

    International Nuclear Information System (INIS)

    Regional cerebral blood volume (rCBV) and flow-to-volume ratio (rCBF/rCBV) were evaluated for clinical significance in comparison to rCBF and findings in X-ray CT (XCT) and radionuclide (RNA) and contrast angiography (CAG). A total of 109 cases were studied within 90 days after cerebrovascular ischemic attack. CBV SPECT was performed following CBF SPECT with I-123-IMP and RNA with Tc-99m-RBC, and processed for subtraction of I-123 contamination fraction. CBF/CBV images was obtained as the count ratio of CBF to CBV image at the same slice-level. Parametric rCBV and rCBF/rCBV were estimated as the count ratio of the focus to the contralateral normal region of interest. Image findings were scored by visual judgement. Student's t-test was applied for statistical analysis with a significance level of p=0.01. The rCBV-ratio was inversely proportional to rCBF/rCBV-ratio, and was different between the two groups with high and low score on flip-flop perfusion in RNA and among three groups with different postictal neurological course. The ratio was the highest for the group of improved course. The rCBF/rCBV-ratio was possibly correlated to rCBF-ratio, and was different between the two groups with high and low score on low density area in XCT, early perfusion in RNA and arterial stenosis in CAG. In the group of improved course, the ratio was different between the second and the third postictal week's duraiton. These results, therefore, suggest that rCBV-ratio reflects collateral perfusion, and is valuable for assessing postictal prognosis in cerebrovascular disease, and that rCBF/rCBV-ratio may reflect regional oxygen extraction fraction, and is valuable for speculating cerebral perfusion reserve. (author)

  10. Feasibility of Quantifying Arterial Cerebral Blood Volume Using Multiphase Alternate Ascending/Descending Directional Navigation (ALADDIN).

    Science.gov (United States)

    Kim, Ki Hwan; Choi, Seung Hong; Park, Sung-Hong

    2016-01-01

    Arterial cerebral blood volume (aCBV) is associated with many physiologic and pathologic conditions. Recently, multiphase balanced steady state free precession (bSSFP) readout was introduced to measure labeled blood signals in the arterial compartment, based on the fact that signal difference between labeled and unlabeled blood decreases with the number of RF pulses that is affected by blood velocity. In this study, we evaluated the feasibility of a new 2D inter-slice bSSFP-based arterial spin labeling (ASL) technique termed, alternate ascending/descending directional navigation (ALADDIN), to quantify aCBV using multiphase acquisition in six healthy subjects. A new kinetic model considering bSSFP RF perturbations was proposed to describe the multiphase data and thus to quantify aCBV. Since the inter-slice time delay (TD) and gap affected the distribution of labeled blood spins in the arterial and tissue compartments, we performed the experiments with two TDs (0 and 500 ms) and two gaps (300% and 450% of slice thickness) to evaluate their roles in quantifying aCBV. Comparison studies using our technique and an existing method termed arterial volume using arterial spin tagging (AVAST) were also separately performed in five subjects. At 300% gap or 500-ms TD, significant tissue perfusion signals were demonstrated, while tissue perfusion signals were minimized and arterial signals were maximized at 450% gap and 0-ms TD. ALADDIN has an advantage of visualizing bi-directional flow effects (ascending/descending) in a single experiment. Labeling efficiency (α) of inter-slice blood flow effects could be measured in the superior sagittal sinus (SSS) (20.8±3.7%.) and was used for aCBV quantification. As a result of fitting to the proposed model, aCBV values in gray matter (1.4-2.3 mL/100 mL) were in good agreement with those from literature. Our technique showed high correlation with AVAST, especially when arterial signals were accentuated (i.e., when TD = 0 ms) (r = 0

  11. Feasibility of Quantifying Arterial Cerebral Blood Volume Using Multiphase Alternate Ascending/Descending Directional Navigation (ALADDIN)

    Science.gov (United States)

    Kim, Ki Hwan; Choi, Seung Hong; Park, Sung-Hong

    2016-01-01

    Arterial cerebral blood volume (aCBV) is associated with many physiologic and pathologic conditions. Recently, multiphase balanced steady state free precession (bSSFP) readout was introduced to measure labeled blood signals in the arterial compartment, based on the fact that signal difference between labeled and unlabeled blood decreases with the number of RF pulses that is affected by blood velocity. In this study, we evaluated the feasibility of a new 2D inter-slice bSSFP-based arterial spin labeling (ASL) technique termed, alternate ascending/descending directional navigation (ALADDIN), to quantify aCBV using multiphase acquisition in six healthy subjects. A new kinetic model considering bSSFP RF perturbations was proposed to describe the multiphase data and thus to quantify aCBV. Since the inter-slice time delay (TD) and gap affected the distribution of labeled blood spins in the arterial and tissue compartments, we performed the experiments with two TDs (0 and 500 ms) and two gaps (300% and 450% of slice thickness) to evaluate their roles in quantifying aCBV. Comparison studies using our technique and an existing method termed arterial volume using arterial spin tagging (AVAST) were also separately performed in five subjects. At 300% gap or 500-ms TD, significant tissue perfusion signals were demonstrated, while tissue perfusion signals were minimized and arterial signals were maximized at 450% gap and 0-ms TD. ALADDIN has an advantage of visualizing bi-directional flow effects (ascending/descending) in a single experiment. Labeling efficiency (α) of inter-slice blood flow effects could be measured in the superior sagittal sinus (SSS) (20.8±3.7%.) and was used for aCBV quantification. As a result of fitting to the proposed model, aCBV values in gray matter (1.4–2.3 mL/100 mL) were in good agreement with those from literature. Our technique showed high correlation with AVAST, especially when arterial signals were accentuated (i.e., when TD = 0 ms) (r = 0

  12. Endotracheal cuff pressure and tracheal mucosal blood flow: endoscopic study of effects of four large volume cuffs.

    OpenAIRE

    Archer, P; Brooker, J

    1984-01-01

    Large volume, low pressure endotracheal tube cuffs are claimed to have less deleterious effect on tracheal mucosa than high pressure, low volume cuffs. Low pressure cuffs, however, may easily be overinflated to yield pressures that will exceed capillary perfusion pressure. Various large volume cuffed endotracheal tubes were studied, including Portex Profile, Searle Sensiv, Mallinkrodt Hi-Lo, and Lanz. Tracheal mucosal blood flow in 40 patients undergoing surgery was assessed using an endoscop...

  13. Arterial pressure variations as parameters of brain perfusion in response to central blood volume depletion and repletion

    OpenAIRE

    Bronzwaer, Anne-Sophie G. T.; Stok, Wim J.; Westerhof, Berend E.; Johannes J. van Lieshout

    2014-01-01

    Rationale: A critical reduction in central blood volume (CBV) is often characterized by hemodynamic instability. Restoration of a volume deficit may be established by goal-directed fluid therapy guided by respiration-related variation in systolic- and pulse pressure (SPV and PPV). Stroke volume index (SVI) serves as a surrogate end-point of a fluid challenge but tissue perfusion itself has not been addressed. Objective: To delineate the relationship between arterial pressure variations, SVI a...

  14. Arterial pressure variations as parameters of brain perfusion in response to central blood volume depletion and repletion

    OpenAIRE

    Anne-SophieG.T.Bronzwaer; WimJ.Stok; BerendE.Westerhof; JohannesJ.Van Lieshout

    2014-01-01

    Rationale: A critical reduction in central blood volume (CBV) is often characterized by hemodynamic instability. Restoration of a volume deficit may be established by goal-directed fluid therapy guided by respiration-related variation in systolic- and pulse pressure (SPV and PPV). Stroke volume index (SVI) serves as a surrogate end-point of a fluid challenge but tissue perfusion itself has not been addressed. Objective: To delineate the relationship between arterial pressure variations, SVI ...

  15. Atrial natriuretic peptide decreases blood volume in intact and anephric rats

    International Nuclear Information System (INIS)

    Atrial natriuretic peptide (ANP) reportedly lowers atrial pressure and increases hematocrit, suggesting venodilation and/or decreased blood volume (BV). To examine these possibilities, rat ANP (99-126) was administered to Inactinanesthetized rats (313 +/- 9 g, +/- SE) at 0.5 μg/kg/min for 30 minutes. Urine flow increased by 0.05 ml/min (p 51Cr-RBC) decreased by 3.4 ml/kg (p < 0.001). Mean circulatory filling pressure, measured by inflating an intracardiac balloon to briefly stop the circulation, did not change. Distribution of BV between the thoracic and spanchnic organs (whole-animal freezing in liquid nitrogen) was not measurably altered. The results suggest that the decrease in CVP was related more to decreased BV than to venodilation. To investigate possible mechanisms for the decreased BV, the same dose of ANP was administered to anephric rats. MAP decreased by 8 mmHg (p < 0.001); hematocrit increased by 2.4 units (p < 0.001) and BV decreased by 1.7 ml/kg (p < 0.05). The results indicate that short-term administration of ANP decreases blood volume by causing intravascular fluid to shift into the interstitium as well as by inducing diuresis

  16. Blood Volume Changes Induced By Low-Intensity Intradialytic Exercise in Long-Term Hemodialysis Patients.

    Science.gov (United States)

    Ookawara, Susumu; Miyazawa, Haruhisa; Ito, Kiyonori; Ueda, Yuichiro; Kaku, Yoshio; Hirai, Keiji; Hoshino, Taro; Mori, Honami; Yoshida, Izumi; Morishita, Yoshiyuki; Tabei, Kaoru

    2016-01-01

    Intradialytic exercise-induced blood volume (BV) reduction may cause intradialytic hypotension in hemodialysis (HD) patients. However, BV recovery time after intradialytic exercise remains unknown. Hemodialysis patients were recruited, and their relative BV change (%ΔBV) were measured with intradialytic exercise (n = 12). After confirming the linearity of %ΔBV for 30 min, patients exercised using a stationary cycle in the supine position. The target exercise intensity was a 10% increase in heart rate (HR), corresponding to relatively low-intensity exercise. Baseline %ΔBV (assumed baseline) were calculated for the 30 min before exercise using linear regression analysis. The mean intradialytic exercise start and end times after HD initiation were 93.0 ± 8.4 and 116.4 ± 8.3 min, respectively, a mean exercise duration of 23.5 ± 2.6 min. Percentage change in blood volume declined rapidly upon exercise initiation and gradually increased above the assumed baseline throughout HD. At the end of HD, %ΔBV in the exercise group was significantly higher than the assumed baseline (measured - assumed baseline %ΔBV: 2.17 ± 0.62%; p = 0.02). Intradialytic exercise with low intensity in the supine position attenuated ultrafiltration-induced BV reduction at the end of HD. Therefore, intradialytic exercise may prevent intradialytic hypotension during later HD, although its intensity was relatively low level. PMID:26720736

  17. The role of blood vessels in high-resolution volume conductor head modeling of EEG.

    Science.gov (United States)

    Fiederer, L D J; Vorwerk, J; Lucka, F; Dannhauer, M; Yang, S; Dümpelmann, M; Schulze-Bonhage, A; Aertsen, A; Speck, O; Wolters, C H; Ball, T

    2016-03-01

    Reconstruction of the electrical sources of human EEG activity at high spatio-temporal accuracy is an important aim in neuroscience and neurological diagnostics. Over the last decades, numerous studies have demonstrated that realistic modeling of head anatomy improves the accuracy of source reconstruction of EEG signals. For example, including a cerebro-spinal fluid compartment and the anisotropy of white matter electrical conductivity were both shown to significantly reduce modeling errors. Here, we for the first time quantify the role of detailed reconstructions of the cerebral blood vessels in volume conductor head modeling for EEG. To study the role of the highly arborized cerebral blood vessels, we created a submillimeter head model based on ultra-high-field-strength (7T) structural MRI datasets. Blood vessels (arteries and emissary/intraosseous veins) were segmented using Frangi multi-scale vesselness filtering. The final head model consisted of a geometry-adapted cubic mesh with over 17×10(6) nodes. We solved the forward model using a finite-element-method (FEM) transfer matrix approach, which allowed reducing computation times substantially and quantified the importance of the blood vessel compartment by computing forward and inverse errors resulting from ignoring the blood vessels. Our results show that ignoring emissary veins piercing the skull leads to focal localization errors of approx. 5 to 15mm. Large errors (>2cm) were observed due to the carotid arteries and the dense arterial vasculature in areas such as in the insula or in the medial temporal lobe. Thus, in such predisposed areas, errors caused by neglecting blood vessels can reach similar magnitudes as those previously reported for neglecting white matter anisotropy, the CSF or the dura - structures which are generally considered important components of realistic EEG head models. Our findings thus imply that including a realistic blood vessel compartment in EEG head models will be helpful to

  18. Improved motion robustness of remote-PPG by using the blood volume pulse signature

    International Nuclear Information System (INIS)

    Remote photoplethysmography (rPPG) enables contact-free monitoring of the blood volume pulse using a color camera. Essentially, it detects the minute optical absorption changes caused by blood volume variations in the skin. In this paper, we show that the different absorption spectra of arterial blood and bloodless skin cause the variations to occur along a very specific vector in a normalized RGB-space. The exact vector can be determined for a given light spectrum and for given transfer characteristics of the optical filters in the camera. We show that this ‘signature’ can be used to design an rPPG algorithm with a much better motion robustness than the recent methods based on blind source separation, and even better than the chrominance-based methods we published earlier. Using six videos recorded in a gym, with four subjects exercising on a range of fitness devices, we confirm the superior motion robustness of our newly proposed rPPG methods. A simple peak detector in the frequency domain returns the correct pulse-rate for 68% of total measurements compared to 60% for the best previous method, while the SNR of the pulse-signal improves from  − 5 dB to  − 4 dB. For a large population of 117 stationary subjects we prove that the accuracy is comparable to the best previous method, although the SNR of the pulse-signal drops from  + 8.4 dB to  + 7.6 dB. We expect the improved motion robustness to significantly widen the application scope of the rPPG-technique. (paper)

  19. Mechanisms of proximal tubule sodium transport regulation that link extracellular fluid volume and blood pressure.

    Science.gov (United States)

    McDonough, Alicia A

    2010-04-01

    One-hundred years ago, Starling articulated the interdependence of renal control of circulating blood volume and effective cardiac performance. During the past 25 years, the molecular mechanisms responsible for the interdependence of blood pressure (BP), extracellular fluid volume (ECFV), the renin-angiotensin system (RAS), and sympathetic nervous system (SNS) have begun to be revealed. These variables all converge on regulation of renal proximal tubule (PT) sodium transport. The PT reabsorbs two-thirds of the filtered Na(+) and volume at baseline. This fraction is decreased when BP or perfusion pressure is increased, during a high-salt diet (elevated ECFV), and during inhibition of the production of ANG II; conversely, this fraction is increased by ANG II, SNS activation, and a low-salt diet. These variables all regulate the distribution of the Na(+)/H(+) exchanger isoform 3 (NHE3) and the Na(+)-phosphate cotransporter (NaPi2), along the apical microvilli of the PT. Natriuretic stimuli provoke the dynamic redistribution of these transporters along with associated regulators, molecular motors, and cytoskeleton-associated proteins to the base of the microvilli. The lipid raft-associated NHE3 remains at the base, and the nonraft-associated NaPi2 is endocytosed, culminating in decreased Na(+) transport and increased PT flow rate. Antinatriuretic stimuli return the same transporters and regulators to the body of the microvilli associated with an increase in transport activity and decrease in PT flow rate. In summary, ECFV and BP homeostasis are, at least in part, maintained by continuous and acute redistribution of transporter complexes up and down the PT microvilli, which affect regulation of PT sodium reabsorption in response to fluctuations in ECFV, BP, SNS, and RAS. PMID:20106993

  20. Optical oximetry of volume-oscillating vascular compartments: contributions from oscillatory blood flow.

    Science.gov (United States)

    Kainerstorfer, Jana M; Sassaroli, Angelo; Fantini, Sergio

    2016-10-01

    We present a quantitative analysis of dynamic diffuse optical measurements to obtain oxygen saturation of hemoglobin in volume oscillating compartments. We used a phasor representation of oscillatory hemodynamics at the heart rate and respiration frequency to separate the oscillations of tissue concentrations of oxyhemoglobin (O) and deoxyhemoglobin (D) into components due to blood volume (subscript V V ) and blood flow (subscript F F ): O=O V +O F O=OV+OF , D=D V +D F D=DV+DF . This is achieved by setting the phase angle Arg(O F )−Arg(O) Arg(OF)−Arg(O) , which can be estimated by a hemodynamic model that we recently developed. We found this angle to be −72  deg −72  deg for the cardiac pulsation at 1 Hz, and −7  deg −7  deg for paced breathing at 0.1 Hz. Setting this angle, we can obtain the oxygen saturation of hemoglobin of the volume-oscillating vascular compartment, S V =|O V |/(|O V |+|D V |) SV=|OV|/(|OV|+|DV|) . We demonstrate this approach with cerebral near-infrared spectroscopy measurements on healthy volunteers at rest (n=4 n=4 ) and during 0.1 Hz paced breathing (n=3 n=3 ) with a 24-channel system. Rest data at the cardiac frequency were used to calculate the arterial saturation, S (a) S(a) ; over all subjects and channels, we found ⟨S V ⟩=⟨S (a) ⟩=0.96±0.02 ⟨SV⟩=⟨S(a)⟩=0.96±0.02 . In the case of paced breathing, we found ⟨S V ⟩=0.66±0.14 ⟨SV⟩=0.66±0.14 , which reflects venous-dominated hemodynamics at the respiratory frequency. PMID:26926870

  1. Radionuclide assessment of peripheral hemodynamics: a new technique for measurement of forearm blood volume and flow

    Energy Technology Data Exchange (ETDEWEB)

    Todo, Y.; Tanimoto, M.; Yamamoto, T.; Iwasaki, T.

    1986-02-01

    A new peripheral hemodynamic measurement system using /sup 99m/Tc-labeled red blood cells has been developed. This method was carried out on 22 normal subjects, 29 with coronary artery disease, and two with dilated cardiomyopathy. Peripheral hemodynamic indices obtained from this method included forearm blood volume (FBV), venous capacity (FVC), venous capacity index (VCI), blood flow (FBF), and vascular resistance (FVR), and were compared with the central hemodynamic parameters of left ventricular filling pressure (LVFP), cardiac output (CO), and total systemic vascular resistance (TSVR) obtained with an invasive technique. The normal values were FBV 8.54 +/- 2.04 ml/100 ml; FVC 4.54 +/- 1.23 ml/100 ml; VCI 65.5 +/- 3.8%; FBF 4.26 +/- 0.56 ml/100 ml/min; and FVR 20.9 +/- 4.4 mmHg/ml/100 ml/min. These values were in good agreement with the values reported using conventional plethysmography. The 16 patients with congestive heart failure (NYHA Class II or III) showed significantly lower FBV, FVC, and FBF values and significantly higher VCI and FVR values than the healthy subjects. Capacitance vessel parameters (FBV, FVC, and VCI) and LVFP, FBF and CO, and FVR and TSVR each showed significant correlation; reproducibility was also good. The advantages of this method are (a) the detector does not come in contact with the region being measured; (b) it is possible to ascertain the absolute quantity of blood in the tissue; (c) extravasation of the plasma component can be ignored; and (d) data processing is simple.

  2. Radionuclide assessment of peripheral hemodynamics: a new technique for measurement of forearm blood volume and flow

    International Nuclear Information System (INIS)

    A new peripheral hemodynamic measurement system using /sup 99m/Tc-labeled red blood cells has been developed. This method was carried out on 22 normal subjects, 29 with coronary artery disease, and two with dilated cardiomyopathy. Peripheral hemodynamic indices obtained from this method included forearm blood volume (FBV), venous capacity (FVC), venous capacity index (VCI), blood flow (FBF), and vascular resistance (FVR), and were compared with the central hemodynamic parameters of left ventricular filling pressure (LVFP), cardiac output (CO), and total systemic vascular resistance (TSVR) obtained with an invasive technique. The normal values were FBV 8.54 +/- 2.04 ml/100 ml; FVC 4.54 +/- 1.23 ml/100 ml; VCI 65.5 +/- 3.8%; FBF 4.26 +/- 0.56 ml/100 ml/min; and FVR 20.9 +/- 4.4 mmHg/ml/100 ml/min. These values were in good agreement with the values reported using conventional plethysmography. The 16 patients with congestive heart failure (NYHA Class II or III) showed significantly lower FBV, FVC, and FBF values and significantly higher VCI and FVR values than the healthy subjects. Capacitance vessel parameters (FBV, FVC, and VCI) and LVFP, FBF and CO, and FVR and TSVR each showed significant correlation; reproducibility was also good. The advantages of this method are (a) the detector does not come in contact with the region being measured; (b) it is possible to ascertain the absolute quantity of blood in the tissue; (c) extravasation of the plasma component can be ignored; and (d) data processing is simple

  3. Plasma volume expansion does not increase maximal cardiac output or VO2 max in lowlanders acclimatized to altitude

    DEFF Research Database (Denmark)

    Calbet, José A L; Rådegran, Göran; Boushel, Robert Christopher;

    2004-01-01

    liter of 6% dextran 70 (BV = 6.32 +/- 0.34 liters). PV expansion had no effect on Qmax, maximal O2 consumption (VO2), and exercise capacity. Despite maximal systemic O2 transport being reduced 19% due to hemodilution after PV expansion, whole body VO2 was maintained by greater systemic O2 extraction (P...

  4. Cord Blood-Derived Hematopoietic Stem/Progenitor Cells: Current Challenges in Engraftment, Infection, and Ex Vivo Expansion

    OpenAIRE

    Katsuhiro Kita; Lee, Jong O; Finnerty, Celeste C.; Herndon, David N

    2011-01-01

    Umbilical cord blood has served as an alternative to bone marrow for hematopoietic transplantation since the late 1980s. Numerous clinical studies have proven the efficacy of umbilical cord blood. Moreover, the possible immaturity of cells in umbilical cord blood gives more options to recipients with HLA mismatch and allows for the use of umbilical cord blood from unrelated donors. However, morbidity and mortality rates associated with hematopoietic malignancies still remain relatively high, ...

  5. Does Preinterventional Flat-Panel Computer Tomography Pooled Blood Volume Mapping Predict Final Infarct Volume After Mechanical Thrombectomy in Acute Cerebral Artery Occlusion?

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Marlies, E-mail: marlies.wagner@kgu.de [Hospital of Goethe University, Institute of Neuroradiology (Germany); Kyriakou, Yiannis, E-mail: yiannis.kyriakou@siemens.com [Siemens AG, Health Care Sector (Germany); Mesnil de Rochemont, Richard du, E-mail: mesnil@em.uni-frankfurt.de [Hospital of Goethe University, Institute of Neuroradiology (Germany); Singer, Oliver C., E-mail: o.singer@em.uni-frankfurt.de [Hospital of Goethe University, Department of Neurology (Germany); Berkefeld, Joachim, E-mail: berkefeld@em.uni-frankfurt.de [Hospital of Goethe University, Institute of Neuroradiology (Germany)

    2013-08-01

    PurposeDecreased cerebral blood volume is known to be a predictor for final infarct volume in acute cerebral artery occlusion. To evaluate the predictability of final infarct volume in patients with acute occlusion of the middle cerebral artery (MCA) or the distal internal carotid artery (ICA) and successful endovascular recanalization, pooled blood volume (PBV) was measured using flat-panel detector computed tomography (FPD CT).Materials and MethodsTwenty patients with acute unilateral occlusion of the MCA or distal ACI without demarcated infarction, as proven by CT at admission, and successful Thrombolysis in cerebral infarction score (TICI 2b or 3) endovascular thrombectomy were included. Cerebral PBV maps were acquired from each patient immediately before endovascular thrombectomy. Twenty-four hours after recanalization, each patient underwent multislice CT to visualize final infarct volume. Extent of the areas of decreased PBV was compared with the final infarct volume proven by follow-up CT the next day.ResultsIn 15 of 20 patients, areas of distinct PBV decrease corresponded to final infarct volume. In 5 patients, areas of decreased PBV overestimated final extension of ischemia probably due to inappropriate timing of data acquisition and misery perfusion.ConclusionPBV mapping using FPD CT is a promising tool to predict areas of irrecoverable brain parenchyma in acute thromboembolic stroke. Further validation is necessary before routine use for decision making for interventional thrombectomy.

  6. Does Preinterventional Flat-Panel Computer Tomography Pooled Blood Volume Mapping Predict Final Infarct Volume After Mechanical Thrombectomy in Acute Cerebral Artery Occlusion?

    International Nuclear Information System (INIS)

    PurposeDecreased cerebral blood volume is known to be a predictor for final infarct volume in acute cerebral artery occlusion. To evaluate the predictability of final infarct volume in patients with acute occlusion of the middle cerebral artery (MCA) or the distal internal carotid artery (ICA) and successful endovascular recanalization, pooled blood volume (PBV) was measured using flat-panel detector computed tomography (FPD CT).Materials and MethodsTwenty patients with acute unilateral occlusion of the MCA or distal ACI without demarcated infarction, as proven by CT at admission, and successful Thrombolysis in cerebral infarction score (TICI 2b or 3) endovascular thrombectomy were included. Cerebral PBV maps were acquired from each patient immediately before endovascular thrombectomy. Twenty-four hours after recanalization, each patient underwent multislice CT to visualize final infarct volume. Extent of the areas of decreased PBV was compared with the final infarct volume proven by follow-up CT the next day.ResultsIn 15 of 20 patients, areas of distinct PBV decrease corresponded to final infarct volume. In 5 patients, areas of decreased PBV overestimated final extension of ischemia probably due to inappropriate timing of data acquisition and misery perfusion.ConclusionPBV mapping using FPD CT is a promising tool to predict areas of irrecoverable brain parenchyma in acute thromboembolic stroke. Further validation is necessary before routine use for decision making for interventional thrombectomy

  7. Subtleties in the calculation of the pressure and pressure tensor of anisotropic particles from volume-perturbation methods and the apparent asymmetry of the compressive and expansive contributions

    OpenAIRE

    Brumby, Paul E; Haslam, Andrew J.; de Miguel, Enrique; Jackson, George

    2010-01-01

    Abstract An effcient and versatile method to calculate the components of the pressure tensor for hard-body fluids of generic shape from the perspective of molecular simulation is presented. After due consideration of all the possible repulsive contributions exerted by molecules upon their surroundings during an anisotropic system expansion, it is observed that such a volume changevcan, for non-spherical molecules, give rise to configurations where overlaps occur. This feature of an...

  8. The Role of Amnion Membrane-Derived Mesenchymal Stem Cells on Differentiation and Expansion of Natural Killer Cell Progenitors Originated From Umbilical Cord Blood Mononuclear Cells

    Directory of Open Access Journals (Sweden)

    Ahmadi

    2015-11-01

    Full Text Available Background Natural killer (NK cells are members of the innate immune system. Their unique properties, including recognition of viral infected and tumor cells without major histocompatibility complex (MHC restriction or prior sensitization, make them a suitable choice for immunotherapy. Low numbers of NK cells in circulating blood is the most important obstacle for this goal. Objectives The aim of this study was to make an optimum in vitro condition to proliferate and differentiate cord blood (CB-NK cell progenitors to mature NK cells, which can be used for cell therapy. Materials and Methods In our study, CB-Mononuclear Cells’ (MNCs CD3+ lymphocytes were positive depleted using immunomagnetic microbeads. This CD3-depleted (CD3-dep CB - MNCs compartment was used for in vitro expansion with or without a layer of amnion membrane mesenchymal stem cells (MSCs in combination with cytokines that are essential for NK cells expansion (IL-2, IL-3, IL-15, and FLT3 ligand. The expansion period lasted for one week. On day seven, immunophenotype and fold expansion of differentiated cells were measured. Results Combination of cytokines and MSC layer yielded significant fold expansion in comparison with cytokines without feeder conditions (day 7: 5.2 ± 1.12 and 2 ± 0.78, respectively, P < 0.05. CD3-/CD56+ cells percentage increased during the culture period in MSCs/with cytokine and cytokine/without feeder, respectively (day 0: 4.4 ± 0.42% and day 7: 22.9 ± 3.6% and 13.9 ± 1.92 % for MSC/with cytokine and cytokine without feeder, respectively. Conclusions Our results suggested that CB-NK cells progenitors could proliferate and differentiate on feeder layer of amnion membrane MSCs in combination with specific cytokines to produce NK cells for immunotherapy.

  9. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B;

    1996-01-01

    to be in accordance with results obtained by other methods. Noncontrast functional MR (fMR) imaging showed signal increases in gray matter, but also inconsistent changes in some white matter regions. CONCLUSION: In this experiment, contrast-enhanced imaging seemed to show a somewhat higher sensitivity towards changes......PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...... by fitting a gamma-variate function to the data. The tissue concentration vs time curves were deconvoluted using an input function obtained by arterial sampling. RESULTS: The ratio of gray to white matter CBV (1.9-2.5) as well as the fractional increase in rCBV during hypercapnia (about 30%) was found...

  10. Reference values for total blood volume and cardiac output in humans

    Energy Technology Data Exchange (ETDEWEB)

    Williams, L.R. [Indiana Univ., South Bend, IN (United States). Division of Liberal Arts and Sciences

    1994-09-01

    Much research has been devoted to measurement of total blood volume (TBV) and cardiac output (CO) in humans but not enough effort has been devoted to collection and reduction of results for the purpose of deriving typical or {open_quotes}reference{close_quotes} values. Identification of normal values for TBV and CO is needed not only for clinical evaluations but also for the development of biokinetic models for ultra-short-lived radionuclides used in nuclear medicine (Leggett and Williams 1989). The purpose of this report is to offer reference values for TBV and CO, along with estimates of the associated uncertainties that arise from intra- and inter-subject variation, errors in measurement techniques, and other sources. Reference values are derived for basal supine CO and TBV in reference adult humans, and differences associated with age, sex, body size, body position, exercise, and other circumstances are discussed.

  11. Loss of alveolar membrane diffusing capacity and pulmonary capillary blood volume in pulmonary arterial hypertension

    Directory of Open Access Journals (Sweden)

    Farha Samar

    2013-01-01

    Full Text Available Abstract Background Reduced gas transfer in patients with pulmonary arterial hypertension (PAH is traditionally attributed to remodeling and progressive loss of pulmonary arterial vasculature that results in decreased capillary blood volume available for gas exchange. Methods We tested this hypothesis by determination of lung diffusing capacity (DL and its components, the alveolar capillary membrane diffusing capacity (Dm and lung capillary blood volume (Vc in 28 individuals with PAH in comparison to 41 healthy individuals, and in 19 PAH patients over time. Using single breath simultaneous measure of diffusion of carbon monoxide (DLCO and nitric oxide (DLNO, DL and Dm were respectively determined, and Vc calculated. Dm and Vc were evaluated over time in relation to standard clinical indicators of disease severity, including brain natriuretic peptide (BNP, 6-minute walk distance (6MWD and right ventricular systolic pressure (RVSP by echocardiography. Results Both DLCO and DLNO were reduced in PAH as compared to controls and the lower DL in PAH was due to loss of both Dm and Vc (all p CO of PAH patients did not change over time, DLNO decreased by 24 ml/min/mmHg/year (p = 0.01. Consequently, Dm decreased and Vc tended to increase over time, which led to deterioration of the Dm/Vc ratio, a measure of alveolar-capillary membrane functional efficiency without changes in clinical markers. Conclusions The findings indicate that lower than normal gas transfer in PAH is due to loss of both Dm and Vc, but that deterioration of Dm/Vc over time is related to worsening membrane diffusion.

  12. Effect of Model Type on the Accuracy of Polarization and Nephelometric Measurements of Red-Blood-Cell Volume

    Science.gov (United States)

    Kugeiko, M. M.; Smunev, D. A.

    2016-05-01

    The effect of using different mathematical models of a red blood cell on the accuracy of the measured average volume for a population of red blood cells was evaluated. The accuracy was estimated based on regression equations between the retrieved microphysical and measured optical properties. Models of a sphere, oblate spheroid, and biconcave discoid represented as a disc with rounded edges and concavities in the middle were analyzed. It was shown that the error of the regression equations when determining the average red-blood-cell volume using the biconcave discoid model was 1%; spheroid, ~8%; and sphere, ~21%. The error of the average volume due to the model is a few percent for the spheroid and ~20% for the sphere.

  13. Cerebral blood flow in temporal lobe epilepsy: a partial volume correction study

    International Nuclear Information System (INIS)

    Previous studies in temporal lobe epilepsy (TLE) have shown that, owing to brain atrophy, positron emission tomography (PET) can overestimate deficits in measures of cerebral function such as glucose metabolism (CMRglu) and neuroreceptor binding. The magnitude of this effect on cerebral blood flow (CBF) is unexplored. The aim of this study was to assess CBF deficits in TLE before and after magnetic resonance imaging-based partial volume correction (PVC). Absolute values of CBF for 21 TLE patients and nine controls were computed before and after PVC. In TLE patients, quantitative CMRglu measurements also were obtained. Before PVC, regional values of CBF were significantly (pglu in middle and inferior temporal cortex, fusiform gyrus and hippocampus both before and after PVC. A significant positive relationship between disease duration and AIs for CMRglu, but not CBF, was detected in hippocampus and amygdala, before but not after PVC. PVC should be used for PET CBF measurements in patients with TLE. Reduced blood flow, in contrast to glucose metabolism, is mainly due to structural changes. (orig.)

  14. Influence of regional cerebral blood volume on voxel-based morphometry.

    Science.gov (United States)

    Zheng, Lei; Cleppien, Dirk; Gass, Natalia; Falfan-Melgoza, Claudia; Vollmayr, Barbara; Hesser, Jürgen; Weber-Fahr, Wolfgang; Sartorius, Alexander

    2016-06-01

    The investigation of structural brain alterations is one focus in research of brain diseases like depression. Voxel-based morphometry (VBM) based on high-resolution 3D MRI images is a widely used non-invasive tool for such investigations. However, the result of VBM might be sensitive to local physiological parameters such as regional cerebral blood volume (rCBV) changes. In order to investigate whether rCBV changes may contribute to variation in VBM, we performed analyses in a study with the congenital learned helplessness (cLH) model for long-term findings. The 3D structural and rCBV data were acquired with T2 -weighted rapid acquisition with relaxation enhancement (RARE) pulse sequences. The group effects were determined by standard statistical parametric mapping (SPM) and biological parametric mapping (BPM) and examined further using atlas-based regions. In our genetic animal model of depression, we found co-occurrence of differences in gray matter volume and rCBV, while there was no evidence of significant interaction between both. However, the multimodal analysis showed similar gray matter differences compared with the standard VBM approach. Our data corroborate the idea that two group VBM differences might not be influenced by rCBV differences in genetically different strains. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27074152

  15. Relationship of blood pressure variability and heart rate variability with prostatic volume in patients with benign prostatic hyperplasia

    Institute of Scientific and Technical Information of China (English)

    金江丽

    2014-01-01

    Objective To investigate the relationship of blood pressure variability(BPV)and heart rate variability(HRV)with prostatic volume(PV)in patients with benign prostatic hyperplasia(BPH).Methods A total of133 patients admitted to our department between January2011 and April 2013 were analyzed retrospectively.The patients were divided into BPH group and non-BPH group according to the PV value.The ambulatory blood

  16. Functional Response of Tumor Vasculature to PaCO2: Determination of Total and Microvascular Blood Volume by MRI

    Directory of Open Access Journals (Sweden)

    Scott D. Packard

    2003-07-01

    Full Text Available In order to identify differences in functional activity, we compared the reactivity of glioma vasculature and the native cerebral vasculature to both dilate and constrict in response to altered PaCO2. Gliomas were generated by unilateral implantation of U87MGdEGFR human glioma tumor cells into the striatum of adult female athymic rats. Relative changes in total and microvascular cerebral blood volume were determined by steady state contrast agent-enhanced magnetic resonance imaging for transitions from normocarbia to hypercarbia and hypocarbia. Although hypercarbia induced a significant increase in both total and microvascular blood volume in normal brain and glioma, reactivity of glioma vasculature was significantly blunted in comparison to normal striatum; glioma total CBV increased by 0.6±0.1%/mm Hg CO2 whereas normal striatum increased by 1.5±0.2%/mm Hg CO2, (P < .0001, group t-test. Reactivity of microvascular blood volume was also significantly blunted. In contrast, hypocarbia decreased both total and microvascular blood volumes more in glioma than in normal striatum. These results indicate that cerebral blood vessels derived by tumor-directed angiogenesis do retain reactivity to CO2. Furthermore, reduced reactivity of tumor vessels to a single physiological perturbation, such as hypercarbia, should not be construed as a generalized reduction of functional activity of the tumor vascular bed.

  17. Reduction in cerebral blood flow volume in infants complicated with hypoxic ischemic encephalopathy resulting in cerebral palsy.

    Science.gov (United States)

    Fukuda, Sumio; Mizuno, Keisuke; Kawai, Satomi; Kakita, Hiroki; Goto, Tatenobu; Hussein, Mohamed Hamed; Daoud, Ghada A; Ito, Tetsuya; Kato, Ineko; Suzuki, Satoshi; Togari, Hajime

    2008-04-01

    Hypoxic ischemic brain can result in cerebral palsy, mental retardation, and learning disabilities in surviving children. The purpose of this study was to elucidate the cerebral blood flow volume in infants complicated with brain damage after the birth. Nine term infants with hypoxic ischemic encephalopathy and 41 normal term infants were studied. Four infants with HIE suffered from CP or mental retardation, and the other five infants exhibited normal neurodevelopment. The mean blood flow velocity and diameter of the internal carotid artery and the vertebral artery were measured for 28 days. The intravascular flow volume was determined by calculating the flow velocity and the cross-sectional area. The ejection fraction and cardiac output were obtained, and the mean blood pressures were recorded. The summed flow volumes in both the ICA and VA, and the total CBFV increased after the birth in both the normal infants and the infants diagnosed with HIE with no disability complications. The total blood flow volume was significantly lower in infants with HIE and CP than in normal infants on days 0, 2, 5, 7, 10, 21, and 28, and significantly lower in infants with HIE and CP than in normal infants with HIE on days 2, 4, and 7. The ejection fraction was significantly lower in infants with HIE than in normal infants only on day 0. Our results suggest that the total cerebral blood supply is decreased in infants with HIE in those complicated with brain damage. PMID:17950550

  18. Evolution, expansion and expression of the Kunitz/BPTI gene family associated with long-term blood feeding in Ixodes Scapularis

    Directory of Open Access Journals (Sweden)

    Dai Shao-Xing

    2012-01-01

    Full Text Available Abstract Background Recent studies of the tick saliva transcriptome have revealed the profound role of salivary proteins in blood feeding. Kunitz/BPTI proteins are abundant in the salivary glands of ticks and perform multiple functions in blood feeding, such as inhibiting blood coagulation, regulating host blood supply and disrupting host angiogenesis. However, Kunitz/BPTI proteins in soft and hard ticks have different functions and molecular mechanisms. How these differences emerged and whether they are associated with the evolution of long-term blood feeding in hard ticks remain unknown. Results In this study, the evolution, expansion and expression of Kunitz/BPTI family in Ixodes scapularis were investigated. Single- and multi-domain Kunitz/BPTI proteins have similar gene structures. Single-domain proteins were classified into three groups (groups I, II and III based on their cysteine patterns. Group I represents the ancestral branch of the Kunitz/BPTI family, and members of this group function as serine protease inhibitors. The group I domain was used as a module to create multi-domain proteins in hard ticks after the split between hard and soft ticks. However, groups II and III, which evolved from group I, are only present and expanded in the genus Ixodes. These lineage-specific expanded genes exhibit significantly higher expression during long-term blood feeding in Ixodes scapularis. Interestingly, functional site analysis suggested that group II proteins lost the ability to inhibit serine proteases and evolved a new function of modulating ion channels. Finally, evolutionary analyses revealed that the expansion and diversification of the Kunitz/BPTI family in the genus Ixodes were driven by positive selection. Conclusions These results suggest that the differences in the Kunitz/BPTI family between soft and hard ticks may be linked to the evolution of long-term blood feeding in hard ticks. In Ixodes, the lineage-specific expanded genes

  19. Determination of the volume of circulating blood by means of in vivo labelled red blood cells with 99mTc pertechnetate and use of a Bulgarian kit

    International Nuclear Information System (INIS)

    A method was proposed for determination of the circulating blood volume (CBV) by means of in vivo labelled red blood cells, which was compared to the routine method with 51Cr-sodium chromate. To the patients concecutively was given 1 g of potassium perchlorate (for blocking of the organs, which actively absorbed the perchnetate ion) and 500 mkg of tin pyrophosphate (Bulgarian kit) with subsequent labelling of the red blood cells with 99mTc-pertechnate (1,8 - 3,7 MBq). The volume of the red blood cells, and hence also CBV, was measured with the use of a modified by the authors formula, in which correction for the individual effectiveness of the cell labelling was done. In comparison with the standard method for in vitro labelling of the red blood cells with 51Cr sodium chromate, the method proposed gave an insignificant difference of 4,16%, but when compared to the commercial tin pyrophosphate (of the firm Mallinckrot - Holland), the Bulgarian kit displayed equivalent qualities. It was concluded that the method has a high accuracy and was easy for execution, cause a low radiation burden of the patient and is suitable for application in nuclear cardiology and radionuclide angiography

  20. Rapid and Efficient Generation of Transgene-Free iPSC from a Small Volume of Cryopreserved Blood.

    Science.gov (United States)

    Zhou, Hongyan; Martinez, Hector; Sun, Bruce; Li, Aiqun; Zimmer, Matthew; Katsanis, Nicholas; Davis, Erica E; Kurtzberg, Joanne; Lipnick, Scott; Noggle, Scott; Rao, Mahendra; Chang, Stephen

    2015-08-01

    Human peripheral blood and umbilical cord blood represent attractive sources of cells for reprogramming to induced pluripotent stem cells (iPSCs). However, to date, most of the blood-derived iPSCs were generated using either integrating methods or starting from T-lymphocytes that have genomic rearrangements thus bearing uncertain consequences when using iPSC-derived lineages for disease modeling and cell therapies. Recently, both peripheral blood and cord blood cells have been reprogrammed into transgene-free iPSC using the Sendai viral vector. Here we demonstrate that peripheral blood can be utilized for medium-throughput iPSC production without the need to maintain cell culture prior to reprogramming induction. Cell reprogramming can also be accomplished with as little as 3000 previously cryopreserved cord blood cells under feeder-free and chemically defined Xeno-free conditions that are compliant with standard Good Manufacturing Practice (GMP) regulations. The first iPSC colonies appear 2-3 weeks faster in comparison to previous reports. Notably, these peripheral blood- and cord blood-derived iPSCs are free of detectable immunoglobulin heavy chain (IGH) and T cell receptor (TCR) gene rearrangements, suggesting they did not originate from B- or T- lymphoid cells. The iPSCs are pluripotent as evaluated by the scorecard assay and in vitro multi lineage functional cell differentiation. Our data show that small volumes of cryopreserved peripheral blood or cord blood cells can be reprogrammed efficiently at a convenient, cost effective and scalable way. In summary, our method expands the reprogramming potential of limited or archived samples either stored at blood banks or obtained from pediatric populations that cannot easily provide large quantities of peripheral blood or a skin biopsy. PMID:25951995

  1. Suitable image parameters and analytical method for quantitatively measuring cerebral blood flow volume with phase-contrast magnetic resonance imaging

    International Nuclear Information System (INIS)

    The aim of this study was to determine suitable image parameters and an analytical method for phase-contrast magnetic resonance imaging (PC-MRI) as a means of measuring cerebral blood flow volume. This was done by constructing an experimental model and applying the results to a clinical application. The experimental model was constructed from the aorta of a bull and circulating isotonic saline. The image parameters of PC-MRI (repetition time, flip angle, matrix, velocity rate encoding, and the use of square pixels) were studied with percent flow volume (the ratio of actual flow volume to measured flow volume). The most suitable image parameters for accurate blood flow measurement were as follows: repetition time, 50 msec; flip angle, 20 degrees; and a 512 x 256 matrix without square pixels. Furthermore, velocity rate encoding should be set ranging from the maximum flow velocity in the vessel to five times this value. The correction in measuring blood flow was done with the intensity of the region of interest established in the background. With these parameters for PC-MRI, percent flow volume was greater than 90%. Using the image parameters for PC-MRI and the analytical method described above, we evaluated cerebral blood flow volume in 12 patients with occlusive disease of the major cervical arteries. The results were compared with conventional xenon computed tomography. The values found with both methods showed good correlation. Thus, we concluded that PC-MRI was a noninvasive method for evaluating cerebral blood flow in patients with occlusive disease of the major cervical arteries. (author)

  2. Left ventricular volume unloading with axial and centrifugal rotary blood pumps.

    Science.gov (United States)

    Giridharan, Guruprasad A; Koenig, Steven C; Soucy, Kevin G; Choi, Young; Pirbodaghi, Tohid; Bartoli, Carlo R; Monreal, Gretel; Sobieski, Michael A; Schumer, Erin; Cheng, Allen; Slaughter, Mark S

    2015-01-01

    Axial (AX) and centrifugal (CFG) rotary blood pumps have gained clinical acceptance for the treatment of advanced heart failure. Differences between AX and CFG designs and mechanism of blood flow delivery may offer clinical advantages. In this study, pump characteristics, and acute physiologic responses during support with AX (HeartMate II) and CFG (HVAD) left ventricular assist devices (LVAD) were investigated in mock loop and chronic ischemic heart failure bovine models. In the mock loop model, pump performance was characterized over a range of pump speeds (HeartMate II: 7,000-11,000 rpm, HVAD: 2,000-3,600 rpm) and fluid viscosities (2.7 cP, 3.2 cP, 3.7 cP). In the ischemic heart failure bovine model, hemodynamics, echocardiography, and end-organ perfusion were investigated. CFG LVAD had a flatter HQ curve, required less power, and had a more linear flow estimation relation than AX LVAD. The flow estimation error for the AX LVAD (±0.9 L/min at 2.7 cP, ±0.7 L/min at 3.2 cP, ±0.8 L/min at 3.7 cP) was higher than the CFG LVAD (±0.5 L/min at 2.7 cP, ±0.2 L/min at 3.2 cP, ±0.5 L/min at 3.7 cP). No differences in acute hemodynamics, echocardiography, or end-organ perfusion between AX and CFG LVAD over a wide range of support were statistically discernible. These findings suggest no pronounced acute differences in LV volume unloading between AX and CFG LVAD. PMID:25635936

  3. Cerebral blood flow in temporal lobe epilepsy: a partial volume correction study

    Energy Technology Data Exchange (ETDEWEB)

    Giovacchini, Giampiero [University Milano-Bicocca, Milan (Italy); Bonwetsch, Robert; Theodore, William H. [National Institute of Neurological Diseases and Strokes, Clinical Epilepsy Section, Bethesda, MD (United States); Herscovitch, Peter [National Institutes of Health, PET Department, Clinical Center, Bethesda, MD (United States); Carson, Richard E. [Yale PET Center, New Haven, CT (United States)

    2007-12-15

    Previous studies in temporal lobe epilepsy (TLE) have shown that, owing to brain atrophy, positron emission tomography (PET) can overestimate deficits in measures of cerebral function such as glucose metabolism (CMR{sub glu}) and neuroreceptor binding. The magnitude of this effect on cerebral blood flow (CBF) is unexplored. The aim of this study was to assess CBF deficits in TLE before and after magnetic resonance imaging-based partial volume correction (PVC). Absolute values of CBF for 21 TLE patients and nine controls were computed before and after PVC. In TLE patients, quantitative CMR{sub glu} measurements also were obtained. Before PVC, regional values of CBF were significantly (p<0.05) lower in TLE patients than in controls in all regions, except the fusiform gyrus contralateral to the epileptic focus. After PVC, statistical significance was maintained in only four regions: ipsilateral inferior temporal cortex, bilateral insula and contralateral amygdala. There was no significant difference between patients and controls in CBF asymmetry indices (AIs) in any region before or after PVC. In TLE patients, AIs for CBF were significantly smaller than for CMR{sub glu} in middle and inferior temporal cortex, fusiform gyrus and hippocampus both before and after PVC. A significant positive relationship between disease duration and AIs for CMR{sub glu}, but not CBF, was detected in hippocampus and amygdala, before but not after PVC. PVC should be used for PET CBF measurements in patients with TLE. Reduced blood flow, in contrast to glucose metabolism, is mainly due to structural changes. (orig.)

  4. A study on the pulmonary mean transit time and the pulmonary blood volume by RI-cardiogram

    International Nuclear Information System (INIS)

    The pulmonary mean transit time and the pulmonary blood volume in cases of cardio-pulmonary disease were measured using Giuntini's method which is considered the most appropriate among radiocardiographic methods. The errors in this method were confirmed to be almost negligible. The results obtained were as follows: 1) The pulmonary mean transit time was related to the systemic mean transit time and markedly prolonged in left heart failure. On the other hand, it was markedly shortened in some cases of chronic pulmonary disease, particularly pulmonary emphysema. 2) The pulmonary blood volume tended to increase in left heart disorders and mitral valve disease and tended to decrease in the chronic pulmonary disease. The decrease was conspicuous particularly in some cases of pulmonary emphysema. 3) A structural change of the pulmonary vascular system in the chronic pulmonary disease appeared to bring about shortening of the pulmonary mean transit time and a decrease in the pulmonary blood volume. The pathophysiology of cardio-pulmonary disease can be more clarified by the RI-cardiogram used in this study, in which the pulmonary mean transit time and the pulmonary blood volume are used as the indicator. (author)

  5. Quantitative measurement of human tissue hepatic blood volume by C{sup 15}O inhalation with positron-emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Hiroki; Masuyama, Mamoru; Koyama, Hiroshi; Oguro, Atsushi; Takahashi, Toshio [Kyoto Prefectural Univ. of Medicine, First Dept. of Surgery, Kyoto (Japan)

    1996-08-01

    In order to estimate the tissue liver function, tissue hepatic blood volume was measured quantitatively and non-invasively using C{sup 15}0 inhalation in conjunction with positron-emission tomography. Fifty-eight patients with normal liver function, 14 patients with chronic hepatitis, 28 patients with hepatic cirrhosis, and 4 patients with obstructive jaundice were studied by positron-emission tomography scan after the single breath inhalation of 20 mCi of high specific activity {sup 1}25O-labeled carbon monoxide. The mean tissue hepatic blood volume was significantly grater in patients with normal livers in patients with chronic hepatitis or hepatic cirrhosis (mean: 20.5, 18.2, and 16.1 ml per 100 cm{sup 3}, respectively, p=8.6x10{sup -8}). Tissue hepatic blood volume (tHBV) correlated with the reaction of the mesenchymal system and protein synthesis, because there was a potent correlation between tHBV and hepatic fibrosis. In normal livers, we were able to demonstrate significant differences in tissue hepatic blood volume among liver segments. (au) 8 refs.

  6. MR-based cerebral blood volume maps as a diagnostic tool for brain tumours

    International Nuclear Information System (INIS)

    Today contrast enhanced MR imaging is a reliable method for detecting mostly distinguishing between different histological types of tumours. In this study we use a MR-based method to measure the regional cerebral blood volume (rCBV). Using this technique we try to judge the grading and vitality of the tumours. 26 patients with various types of brain tumours were examined. 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 into rCBV images. For the tumours rCBV-ratios were calculated relative to the corresponding area in the contralateral hemisphere. In the investigated group all tumours were detected on the basis of a raised rCBV-ratio. Since only vital parts of the tumour are perfused, the rCBV maps may be used to determine the place of biopsy. (orig./MG)

  7. Pulmonary blood volume imaging with dual-energy computed tomography: Spectrum of findings

    Energy Technology Data Exchange (ETDEWEB)

    Hagspiel, K.D., E-mail: kdh2n@virginia.edu [Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, Virginia (United States); Flors, L.; Housseini, A.M.; Phull, A. [Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, Virginia (United States); Ali Ahmad, E. [Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, Virginia (United States); Department of Radiology, Minia University, Minia (Egypt); Bozlar, U.; Norton, P.T. [Department of Radiology and Medical Imaging, University of Virginia Health System, Charlottesville, Virginia (United States); Bonatti, H.J.R. [Department of Surgery, University of Virginia Health System, Charlottesville, Virginia (United States)

    2012-01-15

    Dual-energy (DE) pulmonary blood volume (PBV) computed tomography (CT) has recently become available on clinical CT systems. The underlying physical principle of DECT is the fact that the photoelectric effect is strongly dependent on the CT energies resulting in different degrees of x-ray attenuation for different materials at different energy levels. DECT thus enables the characterization and quantification of iodine within tissues via imaging at different x-ray energies and analysis of attenuation differences. Technical approaches to DECT include dual-source scanners acquiring two scans with different energy levels simultaneously, and single-source CT scanners using sandwich detectors or rapid voltage switching. DE PBV CT enables the creation of iodine maps of the pulmonary parenchyma. Experience to date shows that these studies can provide additional physiological information in patients with acute or chronic pulmonary embolism beyond the pure morphological assessment a standard CT pulmonary angiography (CTPA) provides. It appears also to be promising for the evaluation of patients with obstructive airways disease. This article reviews the physics and technical aspects of DE PBV CT as well as the appearance of normal and abnormal lung tissue on these studies. Special consideration is given to pitfalls and artefacts.

  8. Comparison of pathogen DNA isolation methods from large volumes of whole blood to improve molecular diagnosis of bloodstream infections.

    Directory of Open Access Journals (Sweden)

    Anne J M Loonen

    Full Text Available For patients suffering from bloodstream infections (BSI molecular diagnostics from whole blood holds promise to provide fast and adequate treatment. However, this approach is hampered by the need of large blood volumes. Three methods for pathogen DNA isolation from whole blood were compared, i.e. an enzymatic method (MolYsis, 1-5 ml, the novel non-enzymatic procedure (Polaris, 1-5 ml, and a method that does not entail removal of human DNA (Triton-Tris-EDTA EasyMAG, 200 µl. These methods were evaluated by processing blood spiked with 0-1000 CFU/ml of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. Downstream detection was performed with real-time PCR assays. Polaris and MolYsis processing followed by real-time PCRs enabled pathogen detection at clinically relevant concentrations of 1-10 CFU/ml blood. By increasing sample volumes, concurrent lower cycle threshold (Ct values were obtained at clinically relevant pathogen concentrations, demonstrating the benefit of using larger blood volumes. A 100% detection rate at a concentration of 10 CFU/ml for all tested pathogens was obtained with the Polaris enrichment, whereas comparatively lower detection rates were measured for MolYsis (50-67% and EasyMAG (58-79%. For the samples with a concentration of 1 CFU/ml Polaris resulted in most optimal detection rates of 70-75% (MolYsis 17-50% and TTE-EasyMAG 20-36%. The Polaris method was more reproducible, less labour intensive, and faster (45 minutes (including Qiagen DNA extraction vs. 2 hours (MolYsis. In conclusion, Polaris and MolYsis enrichment followed by DNA isolation and real-time PCR enables reliable and sensitive detection of bacteria and fungi from 5 ml blood. With Polaris results are available within 3 hours, showing potential for improved BSI diagnostics.

  9. Blood Volume, Plasma Volume and Circulation Time in a High-Energy-Demand Teleost, the Yellowfin Tuna (Thunnus Albacares)

    DEFF Research Database (Denmark)

    Brill, R.W.; Cousins, K.L.; Jones, D.R.;

    1998-01-01

    We measured red cell space with 51Cr-labeled red blood cells, and dextran space with 500 kDa fluorescein-isothiocyanate-labeled dextran (FITC-dextran), in two groups of yellowfin tuna (Thunnus albacares). Red cell space was 13.8+/-0.7 ml kg-1 (mean +/- s.e.m.) Assuming a whole- body hematocrit eq...

  10. Pharmacological inhibition of caspase and calpain proteases: a novel strategy to enhance the homing responses of cord blood HSPCs during expansion.

    Directory of Open Access Journals (Sweden)

    V M Sangeetha

    Full Text Available BACKGROUND: Expansion of hematopoietic stem/progenitor cells (HSPCs is a well-known strategy employed to facilitate the transplantation outcome. We have previously shown that the prevention of apoptosis by the inhibition of cysteine proteases, caspase and calpain played an important role in the expansion and engraftment of cord blood (CB derived HSPCs. We hypothesize that these protease inhibitors might have maneuvered the adhesive and migratory properties of the cells rendering them to be retained in the bone marrow for sustained engraftment. The current study was aimed to investigate the mechanism of the homing responses of CB cells during expansion. METHODOLOGY/PRINCIPAL FINDINGS: CB derived CD34(+ cells were expanded using a combination of growth factors with and without Caspase inhibitor -zVADfmk or Calpain 1 inhibitor- zLLYfmk. The cells were analyzed for the expression of homing-related molecules. In vitro adhesive/migratory interactions and actin polymerization dynamics of HSPCs were assessed. In vivo homing assays were carried out in NOD/SCID mice to corroborate these observations. We observed that the presence of zVADfmk or zLLYfmk (inhibitors caused the functional up regulation of CXCR4, integrins, and adhesion molecules, reflecting in a higher migration and adhesive interactions in vitro. The enhanced actin polymerization and the RhoGTPase protein expression complemented these observations. Furthermore, in vivo experiments showed a significantly enhanced homing to the bone marrow of NOD/SCID mice. CONCLUSION/SIGNIFICANCE: Our present study reveals another novel aspect of the regulation of caspase and calpain proteases in the biology of HSPCs. The priming of the homing responses of the inhibitor-cultured HSPCs compared to the cytokine-graft suggests that the modulation of these proteases may help in overcoming the major homing defects prevalent in the expansion cultures thereby facilitating the manipulation of cells for transplant

  11. Analysis of decrease in lung perfusion blood volume with occlusive and non-occlusive pulmonary embolisms

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Yohei, E-mail: ypfranky1@ybb.ne.jp [Department of Radiology, Niigata University Graduate School of Medical and Dental Science (Japan); Yoshimura, Norihiko [Department of Radiology, Niigata University Graduate School of Medical and Dental Science (Japan); Hori, Yoshiro [Department of Radiology, Showa University Fujigaoka Hospital (Japan); Horii, Yosuke; Ishikawa, Hiroyuki [Department of Radiology, Niigata University Graduate School of Medical and Dental Science (Japan); Yamazaki, Motohiko [Department of Radiology, Niigata City General Hospital (Japan); Noto, Yoshiyuki [Department of Radiology, Niigata University Medical and Dental Hospital (Japan); Aoyama, Hidefumi [Department of Radiology, Niigata University Graduate School of Medical and Dental Science (Japan)

    2014-12-15

    Highlights: • The proportion of preserved PE lesions in the non-occlusive group was 76.7% (33/43). • HUs of the iodine map were significantly higher in the non-occlusive group than in the occlusive group. • There was no significant difference in HUs between the non-occlusive and corresponding normal group. - Abstract: Purpose: The aim of this study was to determine if lung perfusion blood volume (lung PBV) with non-occlusive pulmonary embolism (PE) differs quantitatively and visually from that with occlusive PE and to investigate if lung PBV with non-occlusive PE remains the same as that without PE. Materials and methods: Totally, 108 patients suspected of having acute PE underwent pulmonary dual-energy computed tomography angiography (DECTA) between April 2011 and January 2012. Presence of PE on DECTA was evaluated by one radiologist. Two radiologists visually evaluated the PE distribution (segmental or subsegmental) and its nature (occlusive or non-occlusive) on DECTA and classified perfusion in lung PBV as “decreased,” “slightly decreased,” and “preserved”. Two radiologists used a lung PBV application to set a region of interest (ROI) in the center of the lesion and measured HU values of an iodine map. In the same slice as the ROI of the lesion and close to the lesion, another ROI was set in the normal perfusion area without PE, and HUs were measured. The proportion of lesions was compared between the occlusive and non-occlusive groups. HUs were compared among the occlusive, non-occlusive, and corresponding normal groups. Results: Twenty-five patients had 80 segmental or subsegmental lesions. There were 37 and 43 lesions in the occlusive and non-occlusive groups, respectively. The proportion of decreased lesions was 73.0% (27/37) in the occlusive group, while that of preserved lesions in the non-occlusive group was 76.7% (33/43). There was a significant difference in the proportion of lesions (P < 0.001) between the two groups. HUs of the

  12. Analysis of decrease in lung perfusion blood volume with occlusive and non-occlusive pulmonary embolisms

    International Nuclear Information System (INIS)

    Highlights: • The proportion of preserved PE lesions in the non-occlusive group was 76.7% (33/43). • HUs of the iodine map were significantly higher in the non-occlusive group than in the occlusive group. • There was no significant difference in HUs between the non-occlusive and corresponding normal group. - Abstract: Purpose: The aim of this study was to determine if lung perfusion blood volume (lung PBV) with non-occlusive pulmonary embolism (PE) differs quantitatively and visually from that with occlusive PE and to investigate if lung PBV with non-occlusive PE remains the same as that without PE. Materials and methods: Totally, 108 patients suspected of having acute PE underwent pulmonary dual-energy computed tomography angiography (DECTA) between April 2011 and January 2012. Presence of PE on DECTA was evaluated by one radiologist. Two radiologists visually evaluated the PE distribution (segmental or subsegmental) and its nature (occlusive or non-occlusive) on DECTA and classified perfusion in lung PBV as “decreased,” “slightly decreased,” and “preserved”. Two radiologists used a lung PBV application to set a region of interest (ROI) in the center of the lesion and measured HU values of an iodine map. In the same slice as the ROI of the lesion and close to the lesion, another ROI was set in the normal perfusion area without PE, and HUs were measured. The proportion of lesions was compared between the occlusive and non-occlusive groups. HUs were compared among the occlusive, non-occlusive, and corresponding normal groups. Results: Twenty-five patients had 80 segmental or subsegmental lesions. There were 37 and 43 lesions in the occlusive and non-occlusive groups, respectively. The proportion of decreased lesions was 73.0% (27/37) in the occlusive group, while that of preserved lesions in the non-occlusive group was 76.7% (33/43). There was a significant difference in the proportion of lesions (P < 0.001) between the two groups. HUs of the

  13. Radionuclide left ventricular absolute volume determination by ejection fraction measurement data and a left posterior oblique blood pool image

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Shinichiro (Saitama Medical School, Moroyama (Japan))

    1989-09-01

    A new method for the calculation of left ventricular volumes called the 'semi-geometric' method, was reported by Nichols et al in 1984. This method, however, still had certain limitations for practical use. This paper describes a modified semi-geometric method in which the left ventricular volume was obtained from conventional left ventricular ejection fraction measurement data collected from the modified left anterior oblique position with a caudal tilt of 10 degrees or more and a left posterior oblique blood pool image. The left ventricular end-diastolic volumes obtained by this method were compared with those calculated by combining the thermodilution cardiac output and the left ventricular ejection fraction. The correlation coefficient was r=0.93 (n=20). In the phantom experiment, the true volumes and those obtained by this method showed an excellent correlation (r=0.99). This method is considered accurate and practical. (author).

  14. Expansion of CD34+ cells from human umbilical cord blood by FL and/or TPO gene transfected human marrow stromal cell lines

    Institute of Scientific and Technical Information of China (English)

    张毅; 唐佩弦; 金滢; 李秀森; 张双喜; 吴英; 毛宁

    2001-01-01

    To elucidate the effect of gene transfected marrow stromal cell on expansion of human cord blood CD34+ cells, a culture system was established in which FL and TPO genes were transfected into human stromal cell line HFCL. To establish gene transfected stromal cells co-culture system, cord blood CD34+ cells were purified by using a magnetic beads sorting system. The number of all cells and the number of CD34+ cells and CFC (CFU-GM and BFU-E) were counted in different culture systems. The results showed that in all 8 culture systems, SCF+IL-3+HFT manifested the most potent combination, with the number of total nucleated cells increasing by (893.3±52.1)-fold, total progenitor cells (CFC) by (74.5±5.2)-fold and CD34+ cells by 15.7-fold.Maximal expansions of CFC and CD34+ cells were observed at the end of the second week of culture. Within 14 days of culture, (78.1 ± 5.5)-fold and (57.0 ± 19.7)-fold increases in CFU-GM and BFU-E were obtained. Moreover, generation of LTC-IC from amplified CD34+ cells within 28 days was found only in two combinations, I.e. SCF+IL-3+FL+TPO and SCF+IL-3+HFT, and there was no significant difference between these two groups statistically. These results suggest that human umbilical cord blood CD34+ cells can be extensively expanded ex vivo by using gene transfected stromal cells along with cytokines.

  15. Correlation between stroke volume variation and blood volume during hypovolemia%低血容量状态下患者每搏量变异度与血容量的相关性

    Institute of Scientific and Technical Information of China (English)

    李文静; 李健; 彭科

    2014-01-01

    Objective To investigate the correlation between stroke volume variation (SVV) and blood volume during hypovolemia.Methods Twenty ASA Ⅰ or Ⅱ patients,aged 20-64 years,with body mass index (BMI) of 20-30 kg/m2,scheduled for elective orthopedic operation were enrolled in this study.Anesthesia was induced with dexamethasone,midazolam,propofol,fentanyl and cisatracurium,and maintained with sevoflurane,fentanyl and cisatracurium.Then the patients received endotracheal intubation and mechanical ventilation.Heart rate (HR),mean arterial blood pressure (MAP),central venous pressure (CVP),arterial pressure-based cardiac output (APCO),SW,systemic vascular resistance (SVR) and cardiac index (Cl) were recorded 5 minutes after endotracheal intubation.Blood was taken from the central vein at a rate of 30-50 ml/min and the volume was 5% of the whole blood volume,and then haemodynamic parameters mentioned above were recorded after the haemodynamics were kept stable for 5 minutes.Blood was taken again with the method mentioned above and the haemodynamic parameters were recorded.Then 6% hydroxyethyl starch (HES) 130/0.4 was infused at 50-70 ml/min via the right internal jugular vein,and the volume was equal to 5% of the whole blood volume,and then haemodynamic parameters were recorded after the haemodynamics was kept stable for 5 minutes.Fluid replacement was performed again using the method mentioned above and the haemodynamic parameters were recorded.Linear correlation of the changes in blood volume (difference between the blood volume at each time point and the baseline value) with dSVV (difference between the value monitored at each time point and the baseline value) was analyzed.Results Significant changes were found in SW,APCO and Cl after each change in blood volume (P < 0.05 or 0.01),while no significant changes were found in HR,MAP,CVP and SVR after each change in blood volume.The change in blood volume was negatively correlated with dSVV (r =-0.875,P < 0

  16. Positron emission tomography in cerebrovascular disease: The relationship between regional cerebral blood flow, blood volume and oxygen metabolism

    International Nuclear Information System (INIS)

    Positron emission tomography in cerebrovascular disease has demonstrated the importance of the relationship between regional cerebral blood flow and the cerebral metabolic activity. In acute stroke it has been found that within the first hours after the onset of symptoms cerebral blood flow in the affected area is more depressed than cerebral oxygen utilisation. This relative preservation of oxygen utilisation results from an increase in the oxygen extraction ratio far above its normal value. However, the oxygen extraction fraction subsequently falls in the following days indicating the transition from a situation of possibly reversible ischaemia to irreversible infarction. In patients with carotid occlusive disease an increase in the oxygen extraction ratio has been observed only in very few cases. It has been shown, however, that at an earlier stage the relationship between CBF and CBV (as CBF/CBV-ratio) provides a sensitive measure of diminished perfusion pressure which could be helpful for the selection of patients for EC-IC bypass surgery. In patients with sickle cell anaemia it has been found that oxygen delivery to the brain is maintained by an increase in cerebral blood flow, whereas the oxygen extraction ratio is not increased despite the presence of a low oxygen affinity haemoglobin. Preliminary observations in classical migraine suggest an ischaemic situation during the attack. (orig.)

  17. Irradiation of blood, blood compounds and cell culture in equipment of radiotherapy of clinical usage. Study about volume and ideal dose

    International Nuclear Information System (INIS)

    The irradiation of blood bags with the objective of minimizing the graft-versus-host disease in the proceedings of blood transfusion has been consolidated as an indispensable step in the advances of hematopoietic system diseases therapeutics. This practice performed in the great oncological treatment centers requires appropriate equipment (cell irradiators), that due to the high coast, is inaccessible to the majority of the services. The main objective of this work is the show the technique developed by the Radiological Physics Service of the Hospital A. C. Camargo Radiation Department, using the teletherapy equipment of clinical usage available at the Institution. The literature shows that a total dose of 2000 to 3500 c Gy must be administered to all target volume to get an ideal dose/volume relation that proportionates better therapeutic results, neutralizing the cells which are causative of post transfusion reactions of rejection, without prejudicing the other cells that are necessary to the maintenance and preservation of the transplanted person's hematopoietic system functions. With the technic developed for optimization of the irradiation. it is possible to conclude that the utilization of radiotherapy equipment of clinical usage for blood irradiation, substituting cells irradiators, is a good option, permitting safe transfusion of products irradiated with adequate dose. (author)

  18. The measurement of red blood cell volume change induced by Ca2+ based on full field quantitative phase microscopy

    Science.gov (United States)

    Lee, Seungrag; Lee, Ji Yong; Yang, Wenzhong; Kim, Dug Young

    2009-02-01

    We present the measurement of red blood cell (RBC) volume change induced by Ca2+ for a live cell imaging with full field quantitative phase microscopy (FFQPM). FFQPM is based on the Mach-Zehnder interferometer combined with an inverted microscopy system. We present the effective method to obtain a clear image and an accurate volume of the cells. An edge detection technique is used to accurately resolve the boundary between the cell line and the suspension medium. The measurement of the polystyrene bead diameter and volume has been demonstrated the validity of our proposed method. The measured phase profile can be easily converted into thickness profile. The measured polystyrene bead volume and the simulated result are about 14.74 μm3 and 14.14 μm3, respectively. The experimental results of our proposed method agree well with the simulated results within less than 4 %. We have also measured the volume variation of a single RBC on a millisecond time scale. Its mean volume is 54.02 μm3 and its standard deviation is 0.52 μm3. With the proposed system, the shape and volume changes of RBC induced by the increased intracellular Ca2+ are measured after adding ionophore A23187. A discocyte RBC is deformed to a spherocyte due to the increased intracellular Ca2+ in RBC. The volume of the spherocyte is 47.88 μm3 and its standard deviation is 0.19 μm3. We have demonstrated that the volume measurement technique is easy, accurate, and robust method with high volume sensitivity (<0.0000452 μm3) and this provides the ability to study a biological phenomenon in Hematology.

  19. V1a vasopressin receptors maintain normal blood pressure by regulating circulating blood volume and baroreflex sensitivity

    OpenAIRE

    Koshimizu, Taka-aki; Nasa, Yoshihisa; Tanoue, Akito; Oikawa, Ryo; Kawahara, Yuji; Kiyono, Yasushi; ADACHI, TETSUYA; Tanaka, Toshiki; Kuwaki, Tomoyuki; Mori, Toyoki; Takeo, Satoshi; Okamura, Hitoshi; Tsujimoto, Gozoh

    2006-01-01

    Arginine-vasopressin (AVP) is a hormone that is essential for both osmotic and cardiovascular homeostasis, and exerts important physiological regulation through three distinct receptors, V1a, V1b, and V2. Although AVP is used clinically as a potent vasoconstrictor (V1a receptor-mediated) in patients with circulatory shock, the physiological role of vasopressin V1a receptors in blood pressure (BP) homeostasis is ill-defined. In this study, we investigated the functional roles of the V1a recept...

  20. The alveolar-capillary membrane diffusing capacity and the pulmonary capillary blood volume in heart transplant candidates

    OpenAIRE

    Al-Rawas, O; Carter, R.; Stevenson, R; Naik, S; Wheatley, D

    2000-01-01

    OBJECTIVES—To determine the mechanism of impairment of pulmonary transfer factor for carbon monoxide (TLCO) in heart transplant candidates, as this is the most common lung function abnormality.
SETTING—Regional cardiopulmonary transplant centre.
METHODS—TLCO and its components (the diffusing capacity of the alveolar-capillary membrane (DM) and the pulmonary capillary blood volume (VC)) were measured using the Roughton and Forster method and the single breath technique in 38 patients with seve...

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

    OpenAIRE

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

    2012-01-01

    OBJECTIVES: The aim of the current study was to describe a method that assesses the hyperemic microvascular blood plasma volume of the calf musculature. The reversibly albumin binding contrast agent gadofosveset was used in dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) to assess the microvascular status in patients with peripheral arterial disease (PAD) and healthy controls. In addition, the reproducibility of this method in healthy controls was determined. MATERIALS AND METH...

  2. Specificity of Compensatory Reserve and Tissue Oxygenation as Early Predictors of Tolerance to Progressive Reductions in Central Blood Volume.

    Science.gov (United States)

    Howard, Jeffrey T; Janak, Jud C; Hinojosa-Laborde, Carmen; Convertino, Victor A

    2016-09-01

    We previously reported that measurements of muscle oxygen saturation (SmO2) and the compensatory reserve index (CRI) provided earlier indication of reduced central blood volume than standard vital signs (e.g., blood pressure, heart rate, arterial oxygen saturation). In the present study, we hypothesized that the CRI would provide greater sensitivity and specificity to detect progressive decrease in central circulating blood volume compared with SmO2. Continuous noninvasive measures of CRI (calculated from feature changes in the photoplethysmographic arterial waveforms) were collected from 55 healthy volunteer subjects before and during stepwise lower body negative pressure (LBNP) to the onset of hemodynamic decompensation. Near infrared spectroscopy was used on the forearm to obtain deep SmO2, hydrogen ion concentration ([H]), and hemoglobin volume (HbT; decreases reflect vasoconstriction). CRI decreased by 97% in a linear fashion across progressive blood volume loss, with no clinically significant alterations in vital signs. The receiver operating characteristic (ROC) area under the curve (AUC) for the CRI was 0.91, with a sensitivity of 0.87 and specificity of 0.80, when predicting decompensation at progressive levels of LBNP. In comparison, SmO2, [H], and HbT had significantly lower ROC AUC, sensitivity and specificity values for detecting the same outcome. Consistent with our hypothesis, CRI detected central hypovolemia with significantly greater specificity than measures of tissue metabolism. Single measurement of CRI may enable more accurate triage, while CRI monitoring may allow for earlier detection of casualty deterioration. PMID:27058052

  3. Perfusion MRI (dynamic susceptibility contrast imaging) with different measurement approaches for the evaluation of blood flow and blood volume in human gliomas

    DEFF Research Database (Denmark)

    Thomsen, Henrik; Larsson, Elna-Marie; Steffensen, Elena

    2012-01-01

    Background: Perfusion magnetic resonance imaging (MRI) is increasingly used in the evaluation of brain tumors. Relative cerebral blood volume (rCBV) is usually obtained by dynamic susceptibility contrast (DSC) MRI using normal appearing white matter as reference region. The emerging perfusion...... glioblastomas. Results: rCBF and rCBV measurements obtained with the maximum perfusion method were correlated when normalized to white matter (r ¼ 0.60) and to the cerebellum (r ¼ 0.49). Histogram analyses of rCBF and rCBV showed that mean and median values as well as skewness and peak position were correlated...

  4. Application for approval of the Cold Lake Expansion Project: volume 3: environmental impact assessment: socio-economic assessment

    International Nuclear Information System (INIS)

    Anticipated social and economic effects from the construction and operation of the proposed Cold Lake Expansion Project in Alberta were described. The regions and communities that would be directly affected by the project were identified and project impacts with respect to the following areas were analyzed: population and demographics, local economy and labour force, education, health, social and recreational services, protective and emergency services, physical community infrastructure, real estate, and current community planning and land use initiatives. The main sources of information used for the analysis were public statistical data compiled by Statistics Canada, provincial government statistics and municipal planning documents. The overall social impact of the project was expected to range from low to medium. 50 refs., 44 tabs., 6 figs

  5. Effects of intravascular volume expansion on the cardiovascular response to naloxone in a canine model of severe endotoxin shock.

    OpenAIRE

    Evans, S. F.; Hinds, C J; Varley, J. G.

    1984-01-01

    The specific opiate receptor antagonist, naloxone, can produce haemodynamic improvement and increased survival in experimental shock. The efficacy of naloxone therapy in a canine model of endotoxin shock has been evaluated both with and without intravascular volume replacement. Animals were anaesthetized with alpha-chloralose and allowed to breathe spontaneously. A large bolus dose of endotoxin was followed by a continuous infusion and treatment was instituted one hour after the endotoxin bol...

  6. Identification and expansion of cancer stem cells in tumor tissues and peripheral blood derived from gastric adenocarcinoma patients

    Institute of Scientific and Technical Information of China (English)

    Tie Chen; Xinzu Chen; Fang Wang; Fan Zeng; Hong Xu; Jiankun Hu; Xianming Mo; Kun Yang; Jianhua Yu; Wentong Meng; Dandan Yuan; Feng Bi; Fang Liu; Jie Liu; Bing Dai

    2012-01-01

    Gastric cancer is the fourth most common cancer worldwide,with a high rate of death and low 5-year survival rate.To date,there is a lack of efficient therapeutic protocols for gastric cancer.Recent studies suggest that cancer stem cells (CSCs) are responsible for tumor initiation,invasion,metastasis,and resistance to anticancer therapies.Thus,therapies that target gastric CSCs are attractive.However,CSCs in human gastric adenocarcinoma (GAC)have not been described.Here,we identify CSCs in tumor tissues and peripheral blood from GAC patients.CSCs of human GAC (GCSCs) that are isolated from tumor tissues and peripheral blood of patients carried CD44 and CD54 surface markers,generated tumors that highly resemble the original human tumors when injected into immunodeficient mice,differentiated into gastric epithelial cells in vitro,and self-renewed in vivo and in vitro.Our findings suggest that effective therapeutic protocols must target GCSCs.The capture of GCSCs from the circulation of GAC patients also shows great potential for identification of a critical cell population potentially responsible for tumor metastasis,and provides an effective protocol for early diagnosis and longitudinal monitoring of gastric cancer.

  7. Expansion of Cord Blood CD34+ Cells in Presence of zVADfmk and zLLYfmk Improved Their In Vitro Functionality and In Vivo Engraftment in NOD/SCID Mouse

    OpenAIRE

    M, Sangeetha V.; Kale, Vaijayanti P.; Limaye, Lalita S.

    2010-01-01

    Background Cord blood (CB) is a promising source for hematopoietic stem cell transplantations. The limitation of cell dose associated with this source has prompted the ex vivo expansion of hematopoietic stem and progenitor cells (HSPCs). However, the expansion procedure is known to exhaust the stem cell pool causing cellular defects that promote apoptosis and disrupt homing to the bone marrow. The role of apoptotic machinery in the regulation of stem cell compartment has been speculated in mo...

  8. Effects of 5-HT1B/1D receptor agonist rizatriptan on cerebral blood flow and blood volume in normal circulation.

    Science.gov (United States)

    Okazawa, Hidehiko; Tsuchida, Tatsuro; Pagani, Marco; Mori, Tetsuya; Kobayashi, Masato; Tanaka, Fumiko; Yonekura, Yoshiharu

    2006-01-01

    To investigate the vasoconstrictor effect of 5-hydroxytryptamine (5-HT1B/1D) receptor agonists for migraine treatment, changes in cerebral blood flow (CBF) and blood volume induced by rizatriptan were assessed by positron emission tomography (PET). Eleven healthy volunteers underwent PET studies before and after rizatriptan administration. Dynamic PET data were acquired after bolus injection of H2(15)O to analyze CBF and arterial-to-capillary blood volume (V0) images using the three-weighted integral method. After a baseline scan, three further acquisitions were performed at 40 to 50, 60 and 70 to 80 mins after drug administration. Global and regional differences in CBF and V0 between conditions were compared using absolute values in the whole brain and cortical regions, as well as statistical parametric mapping (SPM) analysis. The global and regional values for CBF and V0 decreased significantly after rizatriptan administration compared with the baseline condition. However, both values recovered to baseline within 80 mins after treatment. The maximal reduction in global CBF and V0 was approximately 13% of baseline value. The greatest decrease in CBF was observed approximately 60 mins after drug administration, whereas the maximal reduction in V0 was observed approximately 5 mins earlier. Statistical parametric mapping did not highlight any regional differences between conditions. Thus, in brain circulation, rizatriptan caused significant CBF and V0 decreases, which are consistent with the vasoconstrictor effect of triptans on the large cerebral arteries. The gradual recovery in the late phase from the maximal CBF and V0 decrease suggests that rizatriptan does not affect the cerebral autoregulatory response in small arteries induced by CBF reduction. PMID:15944648

  9. Application for approval of the Cold Lake Expansion Project: volume 2: environmental impact assessment: Part 1: biophysical and resource use assessment. Part 2: impact model descriptions

    International Nuclear Information System (INIS)

    An environmental assessment of the Cold Lake Expansion Project has been conducted to identify major issues of concern by public and government agencies, to determine means to eliminate or reduce those impacts, and to recommend any further efforts required to obtain missing information or monitor impacts. Volume 2 of the environmental impact assessment is divided into two parts. Part 1 (biophysical and resource use assessment) constitutes the primary environmental impact assessment document for the Cold Lake expansion project. It includes technical support documentation in regard to: (1) an assessment of noise impacts, (2) an assessment of greenhouse gas emissions, (3) a conceptual conservation and reclamation plan, (4) a historical resource impact assessment, and (5) a description of effects of oil spills on fish. Part 2 (impact model description) serves a reference document for part 1. It describes the approach taken in developing and assessing the impact models, discusses proposed methods for mitigation and management of residual impacts, and the recommended monitoring requirements for each of the major resource disciplines. The impact models describe the specific pathways through which impacts will occur as a result of interactions between project-related activities and important environmental components. 476 refs., 58 tabs., 23 figs

  10. The effect of amniotic membrane extract on umbilical cord blood mesenchymal stem cell expansion: is there any need to save the amniotic membrane besides the umbilical cord blood?

    Science.gov (United States)

    Vojdani, Zahra; Babaei, Ali; Vasaghi, Attiyeh; Habibagahi, Mojtaba; Talaei-Khozani, Tahereh

    2016-01-01

    Objective(s): Umbilical cord blood is a good source of the mesenchymal stem cells that can be banked, expanded and used in regenerative medicine. The objective of this study was to test whether amniotic membrane extract, as a rich source of growth factors such as basic-fibroblast growth factor, can promote the proliferation potential of the umbilical cord mesenchymal stem cells. Materials and Methods: The study design was interventional. Umbilical cord mesenchymal stem cells were isolated from voluntary healthy infants from hospitals in Shiraz, Iran, cultured in the presence of basic-fibroblast growth factor and amniotic membrane extracts (from pooled - samples), and compared with control cultures. Proliferation assay was performed and duplication number and time were calculated. The expression of stem cell’s specific markers and the differentiation capacity toward osteogenic and adipogenic lineages were evaluated. Results: Amniotic membrane extract led to a significant increase in the proliferation rate and duplication number and a decrease in the duplication time without any change in the cell morphology. Both amniotic membrane extract and basic-fibroblast growth factor altered the expressing of CD44 and CD105 in cell population. Treating basic-fibroblast growth factor but not the amniotic membrane extract favored the differentiation potential of the stem cells toward osteogenic lineage. Conclusion: The amniotic membrane extract administration accelerated cell proliferation and modified the CD marker characteristics which may be due to the induction of differentiation toward a specific lineage. Amniotic membrane extract may enhance the proliferation rate and duplication number of the stem cell through changing the duplication time. PMID:27096069

  11. Successful In Vitro Expansion and Differentiation of Cord Blood Derived CD34+ Cells into Early Endothelial Progenitor Cells Reveals Highly Differential Gene Expression

    Science.gov (United States)

    Topcic, Denijal; Haviv, Izhak; Merivirta, Ruusu-Maaria; Agrotis, Alexander; Leitner, Ephraem; Jowett, Jeremy B.; Bode, Christoph; Lappas, Martha; Peter, Karlheinz

    2011-01-01

    Endothelial progenitor cells (EPCs) can be purified from peripheral blood, bone marrow or cord blood and are typically defined by a limited number of cell surface markers and a few functional tests. A detailed in vitro characterization is often restricted by the low cell numbers of circulating EPCs. Therefore in vitro culturing and expansion methods are applied, which allow at least distinguishing two different types of EPCs, early and late EPCs. Herein, we describe an in vitro culture technique with the aim to generate high numbers of phenotypically, functionally and genetically defined early EPCs from human cord blood. Characterization of EPCs was done by flow cytometry, immunofluorescence microscopy, colony forming unit (CFU) assay and endothelial tube formation assay. There was an average 48-fold increase in EPC numbers. EPCs expressed VEGFR-2, CD144, CD18, and CD61, and were positive for acetylated LDL uptake and ulex lectin binding. The cells stimulated endothelial tube formation only in co-cultures with mature endothelial cells and formed CFUs. Microarray analysis revealed highly up-regulated genes, including LL-37 (CAMP), PDK4, and alpha-2-macroglobulin. In addition, genes known to be associated with cardioprotective (GDF15) or pro-angiogenic (galectin-3) properties were also significantly up-regulated after a 72 h differentiation period on fibronectin. We present a novel method that allows to generate high numbers of phenotypically, functionally and genetically characterized early EPCs. Furthermore, we identified several genes newly linked to EPC differentiation, among them LL-37 (CAMP) was the most up-regulated gene. PMID:21858032

  12. Integrated analysis of halogenated organic pollutants in sub-millilitre volumes of venous and umbilical cord blood sera

    Energy Technology Data Exchange (ETDEWEB)

    Grimalt, Joan O.; Carrizo, Daniel; Otero, Raquel; Vizcaino, Esther [Institute of Environmental Assessment and Water Research (IDAeA-CSIC), Department of Environmental Chemistry, Barcelona, Catalonia (Spain); Howsam, Mike [Universite de Lille 2, Centre Universitaire de Mesure et d' Analyse, Faculte de Pharmacie, Lille (France); Rodrigues de Marchi, Mary Rosa [Institute of Chemistry UNESP, Department of Analytical Chemistry, Araraquara, SP (Brazil)

    2010-03-15

    A rapid, robust and economical method for the analysis of persistent halogenated organic compounds in small volumes of human serum and umbilical cord blood is described. The pollutants studied cover a broad range of molecules of contemporary epidemiological and legislative concern, including polychlorobiphenyls (PCBs), polychlorobenzenes (CBs), hexachlorocyclohexanes (HCHs), DDTs, polychlorostyrenes (PCSs) and polybromodiphenyl ethers (PBDEs). Extraction and clean-up with n-hexane and concentrated sulphuric acid was followed with analysis by gas chromatography coupled to electron capture (GC-ECD) and GC coupled to negative ion chemical ionisation mass spectrometry (GC-NICI-MS). The advantages of this method rest in the broad range of analytes and its simplicity and robustness, while the use of concentrated sulphuric acid extraction/clean-up destroys viruses that may be present in the samples. Small volumes of reference serum between 50 and 1000{mu}L were extracted and the limits of detection/quantification and repeatability were determined. Recoveries of spiked compounds for the extraction of small volumes ({>=}300 {mu}L) of the spiked reference serum were between 90% and 120%. The coefficients of variation of repeatability ranged from 0.1-14%, depending on the compound. Samples of 4-year-old serum and umbilical cord blood (n=73 and 40, respectively) from a population inhabiting a village near a chloro-alkali plant were screened for the above-mentioned halogenated pollutants using this method and the results are briefly described. (orig.)

  13. Detecting variations of blood volume shift due to heart beat from respiratory inductive plethysmography measurements in man

    International Nuclear Information System (INIS)

    The simultaneous study of the cardiac and respiratory activities and their interactions is of great physiological and clinical interest. For this purpose, we want to investigate if respiratory inductive plethysmography (RIP) can be used for cardiac functional exploration. We propose a system, based on RIP technology and time-scale approaches of signal processing, for the extraction of cardiac information. This study focuses on the monitoring of blood volume shift due to heart beat, noted ▵Vtrc and investigates RIP for the detection of ▵Vtrc variations by comparison to stroke volume (SV) variations estimated by impedance cardiography (IMP). We proposed a specific respiratory protocol assumed to induce significant variations of the SV. Fifteen healthy volunteers in the seated and supine positions were asked to alternate rest respiration and maneuvers, consisting in blowing into a manometer. A multi-step treatment including a variant of empirical mode decomposition was applied on RIP signals to extract cardiac volume signals and estimate beat-to-beat ▵Vtrc. These were averaged in quasi-stationary states at rest and during the respiratory maneuvers, and analysed in view of SV estimations from IMP signals simultaneously acquired. Correlation and statistical tests over the data show that RIP can be used to detect variations of the cardiac blood shift in healthy young subjects. (paper)

  14. Carotid blood flow measured by an ultrasonic volume flowmeter in carotid stenosis and patients with dementia.

    OpenAIRE

    UEMATSU, S.; Folstein, M F

    1985-01-01

    The volume flowmeter is a simple, noninvasive Doppler ultrasound technique that provides accurate measurement of carotid artery diameter and flow. The device provides a useful laboratory test that can aid significantly in diagnosis of carotid stenosis and dementia.

  15. Intraprocedural blood volume measurement using C-arm CT as a predictor for treatment response of malignant liver tumours undergoing repetitive transarterial chemoembolization (TACE)

    International Nuclear Information System (INIS)

    To evaluate feasibility of measuring parenchymal blood volume (PBV) of malignant hepatic tumours using C-arm CT, test the changes in PBV following repeated transarterial chemoembolization (TACE) and correlate these changes with the change in tumour size in MRI. 111 patients with liver malignancy were included. Patients underwent MRI and TACE in a 4- to 6-week interval. During intervention C-arm CT was performed. Images were post-processed to generate PBV maps. Blood volume data in C-arm CT and change in size in MRI were evaluated. The correlation between PBV and size was tested using Spearman rank test. Pre-interventional PBV maps showed a mean blood volume of 84.5 ml/1000 ml ± 62.0, follow-up PBV maps after multiple TACE demonstrated 61.1 ml/1000 ml ± 57.5. The change in PBV was statistically significant (p = 0.02). Patients with initial tumour blood volume >100 ml/1000 ml dropped 7.1 % in size and 47.2 % in blood volume; 50-100 ml/1000 ml dropped 4.6 % in size and 25.7 % in blood volume; and <50 ml/1000 ml decreased 2.8 % in size and increased 82.2 % in blood volume. PBV measurement of malignant liver tumours using C-arm CT is feasible. Following TACE PBV decreased significantly. Patients with low initial PBV show low local response rates and further increase in blood volume, whereas high initial tumour PBV showed better response to TACE. (orig.)

  16. Intraprocedural blood volume measurement using C-arm CT as a predictor for treatment response of malignant liver tumours undergoing repetitive transarterial chemoembolization (TACE)

    Energy Technology Data Exchange (ETDEWEB)

    Vogl, Thomas J.; Schaefer, Patrik; Lehnert, Thomas; Mbalisike, Emmanuel; Hammerstingl, Renate; Eichler, Katrin; Zangos, Stephan [Johann Wolfgang Goethe-University Frankfurt, Institute for Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Nour-Eldin, Nour-Eldin A. [Johann Wolfgang Goethe-University Frankfurt, Institute for Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Cairo University, Department of Radiology, Faculty of Medicine (Kasr Al-Ainy), Cairo (Egypt); Ackermann, Hanns [Johann Wolfgang Goethe-University Frankfurt, Department of Biomedical Statistics, Frankfurt am Main (Germany); Naguib, Nagy N.N. [Johann Wolfgang Goethe-University Frankfurt, Institute for Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Alexandria University, Department of Radiology, Faculty of Medicine, Alexandria (Egypt)

    2016-03-15

    To evaluate feasibility of measuring parenchymal blood volume (PBV) of malignant hepatic tumours using C-arm CT, test the changes in PBV following repeated transarterial chemoembolization (TACE) and correlate these changes with the change in tumour size in MRI. 111 patients with liver malignancy were included. Patients underwent MRI and TACE in a 4- to 6-week interval. During intervention C-arm CT was performed. Images were post-processed to generate PBV maps. Blood volume data in C-arm CT and change in size in MRI were evaluated. The correlation between PBV and size was tested using Spearman rank test. Pre-interventional PBV maps showed a mean blood volume of 84.5 ml/1000 ml ± 62.0, follow-up PBV maps after multiple TACE demonstrated 61.1 ml/1000 ml ± 57.5. The change in PBV was statistically significant (p = 0.02). Patients with initial tumour blood volume >100 ml/1000 ml dropped 7.1 % in size and 47.2 % in blood volume; 50-100 ml/1000 ml dropped 4.6 % in size and 25.7 % in blood volume; and <50 ml/1000 ml decreased 2.8 % in size and increased 82.2 % in blood volume. PBV measurement of malignant liver tumours using C-arm CT is feasible. Following TACE PBV decreased significantly. Patients with low initial PBV show low local response rates and further increase in blood volume, whereas high initial tumour PBV showed better response to TACE. (orig.)

  17. Imaging changes in blood volume and oxygenation in the newborn infant brain using three-dimensional optical tomography

    International Nuclear Information System (INIS)

    Induced haemodynamic and blood oxygenation changes occurring within the brain of a ventilated newborn infant have been imaged in three dimensions using optical tomography. Noninvasive measurements of the flight times of transmitted light were acquired during illumination of the brain by laser pulses at wavelengths of 780 nm and 815 nm. The oxygen and carbon dioxide partial pressures were adjusted through alterations to the ventilator settings, resulting in changes to the cerebral blood volume and oxygenation. Three-dimensional images were generated using the physiologically associated differences in the measured data, obviating the need for data calibration using a separate reference measurement. The results exhibit large changes in absorption coefficient at both wavelengths. Images corresponding to differences in concentrations of oxy- and deoxyhaemoglobin are in qualitative agreement with known physiological data

  18. Spatiotemporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    Science.gov (United States)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shanbin; Cheng, Haiying; Zeng, Shaoqun

    2003-07-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%) 2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  19. Simultaneous evaluation of brain tumour metabolism, structure and blood volume using [(18)F]-fluoroethyltyrosine (FET) PET/MRI

    DEFF Research Database (Denmark)

    Henriksen, Otto M; Larsen, Vibeke A; Muhic, Aida; Hansen, Adam E; Larsson, Henrik B W; Poulsen, Hans S; Law, Ian

    2016-01-01

    at least one modality for any pair of modalities. In 56 % of the patients susceptibility artefacts in DSC BV maps overlapped the tumour on MRI. CONCLUSION: The study demonstrated that although tumour volumes determined by BV MRI and FET PET were quantitatively correlated, their spatial congruence in......PURPOSE: Both [(18)F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of...... simultaneous structural MRI, BV MRI and FET PET of gliomas using an integrated PET/MRI scanner and to assess the spatial and quantitative agreement in tumour imaging between BV MRI and FET PET. METHODS: A total of 32 glioma patients underwent a 20-min static simultaneous PET/MRI acquisition on a Siemens m...

  20. Effect of Buddhist meditation on serum cortisol and total protein levels, blood pressure, pulse rate, lung volume and reaction time.

    Science.gov (United States)

    Sudsuang, R; Chentanez, V; Veluvan, K

    1991-09-01

    Serum cortisol and total protein levels, blood pressure, heart rate, lung volume, and reaction time were studied in 52 males 20-25 years of age practicing Dhammakaya Buddhist meditation, and in 30 males of the same age group not practicing meditation. It was found that after meditation, serum cortisol levels were significantly reduced, serum total protein level significantly increased, and systolic pressure, diastolic pressure and pulse rate significantly reduced. Vital capacity, tidal volume and maximal voluntary ventilation were significantly lower after meditation than before. There were also significant decreases in reaction time after mediation practice. The percentage decrease in reaction time during meditation was 22%, while in subjects untrained in meditation, the percentage decrease was only 7%. Results from these studies indicate that practising Dhammakaya Buddhist meditation produces biochemical and physiological changes and reduces the reaction time. PMID:1801007

  1. Volume Tracking: A new method for quantitative assessment and visualization of intracardiac blood flow from three-dimensional, time-resolved, three-component magnetic resonance velocity mapping

    International Nuclear Information System (INIS)

    Functional and morphological changes of the heart influence blood flow patterns. Therefore, flow patterns may carry diagnostic and prognostic information. Three-dimensional, time-resolved, three-directional phase contrast cardiovascular magnetic resonance (4D PC-CMR) can image flow patterns with unique detail, and using new flow visualization methods may lead to new insights. The aim of this study is to present and validate a novel visualization method with a quantitative potential for blood flow from 4D PC-CMR, called Volume Tracking, and investigate if Volume Tracking complements particle tracing, the most common visualization method used today. Eight healthy volunteers and one patient with a large apical left ventricular aneurysm underwent 4D PC-CMR flow imaging of the whole heart. Volume Tracking and particle tracing visualizations were compared visually side-by-side in a visualization software package. To validate Volume Tracking, the number of particle traces that agreed with the Volume Tracking visualizations was counted and expressed as a percentage of total released particles in mid-diastole and end-diastole respectively. Two independent observers described blood flow patterns in the left ventricle using Volume Tracking visualizations. Volume Tracking was feasible in all eight healthy volunteers and in the patient. Visually, Volume Tracking and particle tracing are complementary methods, showing different aspects of the flow. When validated against particle tracing, on average 90.5% and 87.8% of the particles agreed with the Volume Tracking surface in mid-diastole and end-diastole respectively. Inflow patterns in the left ventricle varied between the subjects, with excellent agreement between observers. The left ventricular inflow pattern in the patient differed from the healthy subjects. Volume Tracking is a new visualization method for blood flow measured by 4D PC-CMR. Volume Tracking complements and provides incremental information compared to particle

  2. Comparative evaluation of cerebral blood volume and cerebral blood flow in acute ischemic stroke by using perfusion-weighted MR imaging and SPECT

    International Nuclear Information System (INIS)

    Purpose: To investigate the relationship between relative cerebral blood volume (CBV) measured with perfusion-weighted (PW) MR imaging and relative cerebral blood flow (CBF) measured with SPECT in acute ischemic stroke. Material and Methods: Fifteen patients who had acute unilateral middle cerebral artery occlusion underwent both PW MR imaging and 99mTc-HMPAO SPECT with an interval less than 20 minutes between the two examinations within 6 hours after stroke onset. Lesion-to-contralateral relative CBV and CBF ratios measured in multiple regions of interest were compared to evaluate the relationship of the two parameters. Results: An overall linear relationship was found between relative CBV and relative CBF ratios (R2=0.54, p0.05). Regions with evolving infarction had more severe hypoperfusion (mean relative CBF ratio, 0.38±0.22) than regions without (mean relative CBF ratio, 0.70±0.13) (p<0.0001). Conclusion: A significant linear relationship existed between relative CBV and relative CBF in acute ischemic stroke, although relative CBV did not change linearly to relative CBF in mild hypoperfusion. Relative CBV can be used as an alternative to relative CBF within 6 hours after stroke onset, particularly in regions with severe hypoperfusion proceeding to infarction

  3. Elevated HbA1c Levels Are Associated with the Blunted Autonomic Response Assessed by Heart Rate Variability during Blood Volume Reduction.

    Science.gov (United States)

    Kamakura, Miho; Maruyama, Ryoko

    2016-01-01

    A high glycemic status increases the risk for autonomic dysfunction and cardiovascular failure. The aim of this study was to investigate time-dependent changes in the autonomic response and cardiovascular dynamics and the association between the level of hemoglobin A1c (HbA1c) and autonomic response during blood volume reduction. The study population consisted of 26 preoperative participants who were scheduled for autologous blood donation (200-400 mL of whole blood) for intraoperative or postoperative use. These participants without circulatory, respiratory, or brain disease and diabetes mellitus were grouped according to their HbA1c levels: rate variability (HRV) to quantify cardiac autonomic regulation throughout blood donation. During blood volume reduction, which was about 10% of the circulating blood volume, the BP and heart rate varied within normal ranges in both groups. The high-frequency (HF) component, an index of parasympathetic nerve activity, and the ratio of low-frequency (LF) to HF components (LF/HF), an index of sympathetic nerve activity, significantly decreased and increased with the progression of blood volume reduction, respectively, in the HbA1c < 6.5% group. In contrast, in the HbA1c ≥ 6.5% group, the HF component did not significantly change, and the increase in the LF/HF ratio was delayed. Time-dependent changes in HRV were related to blood volume reduction only in the HbA1c < 6.5% group. Thus, elevated HbA1c levels are associated with the decrease in the autonomic response induced by blood volume reduction. PMID:27615262

  4. Comparison of blood volume pulse and skin conductance responses to mental and affective stimuli at different anatomical sites

    International Nuclear Information System (INIS)

    Measurements of blood volume pulse (BVP) and skin conductance are commonly used as indications of psychological arousal in affective computing and human–machine interfaces. To date, palmar surfaces remain the primary site for these measurements. Placement of sensors on palmar surfaces, however, is undesirable when recordings are fraught with motion and pressure artifacts. These artifacts are frequent when the human participant has involuntary movements as in hyperkinetic cerebral palsy. This motivates the use of alternative measurement sites. The present study examined the correlation between measurements of blood volume pulse and skin conductance obtained from three different sites on the body (fingers, toes and ear for BVP; fingers, toes and arch of the foot for skin conductance) in response to cognitive and affective stimuli. The results of this pilot study indicated significant inter-site correlation among signal features derived from different sites, with the exception of BVP amplitude, the number of electrodermal reactions and the slope of the electrodermal activity response. We attribute these differences in part to inter-site discrepancies in local skin conditions, such as skin temperature. Despite these differences, significant changes from baseline were present in the responses to the cognitive and affective stimuli at non-palmar sites, suggesting that these sites may provide viable signal measurements for use in affective computing and human–machine interface applications

  5. Peripheral arterial volume distensibility: significant differences with age and blood pressure measured using an applied external pressure

    International Nuclear Information System (INIS)

    A new arterial distensibility measurement technique was assessed in 100 healthy normotensive subjects. Arterial transmural pressures on the whole right arm were reduced with a 50 cm long cuff inflated to 10, 20, 30 and 40 mmHg. The electrocardiogram, and finger and ear photoplethysmograms were recorded simultaneously. Arm pulse propagation time, pulse wave velocity (PWV) and arterial volume distensibility were determined. With a 40 mmHg reduction in transmural pressure, arm pulse propagation time increased from 61 to 83 ms, PWV decreased from 12 to 8 m s−1 and arterial distensibility increased from 0.102% to 0.232% per mmHg (all P < 0.0001). At all cuff pressures, arterial distensibility was significantly related to resting mean arterial pressure (MAP), diastolic blood pressure (DBP) and age, and for systolic blood pressure at 30 and 40 mmHg (all P < 0.05). At 40 mmHg cuff pressure, arterial distensibility fell by 54% for a MAP increase from 75 to 105 mmHg, 57% for a DBP increase from 60 to 90 mmHg and 47% for an age increase from 20 to 70 years. These changes were more than double than those without cuff pressure. Our technique showed that systemic volume distensibility of the peripheral arm artery reduced with age, with a greater effect at higher external and lower transmural pressures

  6. Macrophages regulate salt-dependent volume and blood pressure by a vascular endothelial growth factor-C-dependent buffering mechanism.

    Science.gov (United States)

    Machnik, Agnes; Neuhofer, Wolfgang; Jantsch, Jonathan; Dahlmann, Anke; Tammela, Tuomas; Machura, Katharina; Park, Joon-Keun; Beck, Franz-Xaver; Müller, Dominik N; Derer, Wolfgang; Goss, Jennifer; Ziomber, Agata; Dietsch, Peter; Wagner, Hubertus; van Rooijen, Nico; Kurtz, Armin; Hilgers, Karl F; Alitalo, Kari; Eckardt, Kai-Uwe; Luft, Friedrich C; Kerjaschki, Dontscho; Titze, Jens

    2009-05-01

    In salt-sensitive hypertension, the accumulation of Na(+) in tissue has been presumed to be accompanied by a commensurate retention of water to maintain the isotonicity of body fluids. We show here that a high-salt diet (HSD) in rats leads to interstitial hypertonic Na(+) accumulation in skin, resulting in increased density and hyperplasia of the lymphcapillary network. The mechanisms underlying these effects on lymphatics involve activation of tonicity-responsive enhancer binding protein (TonEBP) in mononuclear phagocyte system (MPS) cells infiltrating the interstitium of the skin. TonEBP binds the promoter of the gene encoding vascular endothelial growth factor-C (VEGF-C, encoded by Vegfc) and causes VEGF-C secretion by macrophages. MPS cell depletion or VEGF-C trapping by soluble VEGF receptor-3 blocks VEGF-C signaling, augments interstitial hypertonic volume retention, decreases endothelial nitric oxide synthase expression and elevates blood pressure in response to HSD. Our data show that TonEBP-VEGF-C signaling in MPS cells is a major determinant of extracellular volume and blood pressure homeostasis and identify VEGFC as an osmosensitive, hypertonicity-driven gene intimately involved in salt-induced hypertension. PMID:19412173

  7. Effect of heparin addition on expansion of cord blood hematopoietic progenitor cells in three-dimensional coculture with stromal cells in nonwoven fabrics.

    Science.gov (United States)

    Okamoto, Toru; Takagi, Mutsumi; Soma, Toshihiro; Ogawa, Hiroyasu; Kawakami, Manabu; Mukubo, Masaaki; Kubo, Kazusuke; Sato, Reiko; Toma, Kazunori; Yoshida, Toshiomi

    2004-01-01

    Primary human cord blood mononuclear cells (CB MNCs) were inoculated into layers of primary human bone marrow stromal cells prepared in a nonwoven fabric porous carrier [three dimensional (3-D)] or on a dish [two dimensional (2-D)] using a cytokine-free medium and were cultured for 7 days with or without the addition of heparin. The number of progenitor cells increased threefold during the 3-D coculture, whereas it decreased in the 2-D culture. Heparin addition to the 3-D coculture further increased the number of progenitors twofold, whereas the addition of desulfated heparin had no effect. The heparin effect was also observed in a 3-D culture of CB MNCs without stromal cells when conditioned medium was employed. The coating of the carrier with N-(O-beta-(6-O-sulfogalactopyranosyl)-6-oxyhexyl)-3,5-bis (dodecyloxy)-benzamide instead of heparin addition also increased the number of progenitor cells in the 3-D culture of CB MNCs without stromal cells when the conditioned medium was employed. The 3-D coculture constructed with nonwoven fabrics and stromal cells was clearly superior to the 2-D culture because of the expansion of CB hematopoietic progenitor cells without cytokine addition. Heparin addition to the 3-D coculture further increased the number of progenitor cells, which may result from a synergistic effect of soluble cytokines produced by stromal cells with the sulfur group of heparin. PMID:15739052

  8. Association between cell-bound blood amyloid-β(1–40) levels and hippocampus volume

    OpenAIRE

    Sotolongo-Grau, Oscar; Pesini, Pedro; Valero, Sergi; Lafuente, Asunción; Buendía, Mar; Pérez-Grijalba, Virginia; José, Itziar San; Ibarria, Marta; Tejero, Miguel A; Giménez, Joan; Hernández, Isabel; Tárraga, Lluís; Ruiz, Agustín; Boada, Mercé; Sarasa, Manuel

    2014-01-01

    Introduction The identification of early, preferably presymptomatic, biomarkers and true etiologic factors for Alzheimer’s disease (AD) is the first step toward establishing effective primary and secondary prevention programs. Consequently, the search for a relatively inexpensive and harmless biomarker for AD continues. Despite intensive research worldwide, to date there is no definitive plasma or blood biomarker indicating high or low risk of conversion to AD. Methods Magnetic resonance imag...

  9. Model estimation of cerebral hemodynamics between blood flow and volume changes: a data-based modeling approach.

    Science.gov (United States)

    Wei, Hua-Liang; Zheng, Ying; Pan, Yi; Coca, Daniel; Li, Liang-Min; Mayhew, J E W; Billings, Stephen A

    2009-06-01

    It is well known that there is a dynamic relationship between cerebral blood flow (CBF) and cerebral blood volume (CBV). With increasing applications of functional MRI, where the blood oxygen-level-dependent signals are recorded, the understanding and accurate modeling of the hemodynamic relationship between CBF and CBV becomes increasingly important. This study presents an empirical and data-based modeling framework for model identification from CBF and CBV experimental data. It is shown that the relationship between the changes in CBF and CBV can be described using a parsimonious autoregressive with exogenous input model structure. It is observed that neither the ordinary least-squares (LS) method nor the classical total least-squares (TLS) method can produce accurate estimates from the original noisy CBF and CBV data. A regularized total least-squares (RTLS) method is thus introduced and extended to solve such an error-in-the-variables problem. Quantitative results show that the RTLS method works very well on the noisy CBF and CBV data. Finally, a combination of RTLS with a filtering method can lead to a parsimonious but very effective model that can characterize the relationship between the changes in CBF and CBV. PMID:19174333

  10. Are you bleeding? Validation of a machine-learning algorithm for determination of blood volume status: application to remote triage.

    Science.gov (United States)

    Rickards, Caroline A; Vyas, Nisarg; Ryan, Kathy L; Ward, Kevin R; Andre, David; Hurst, Gennifer M; Barrera, Chelsea R; Convertino, Victor A

    2014-03-01

    Due to limited remote triage monitoring capabilities, combat medics cannot currently distinguish bleeding soldiers from those engaged in combat unless they have physical access to them. The purpose of this study was to test the hypothesis that low-level physiological signals can be used to develop a machine-learning algorithm for tracking changes in central blood volume that will subsequently distinguish central hypovolemia from physical activity. Twenty-four subjects underwent central hypovolemia via lower body negative pressure (LBNP), and a supine-cycle exercise protocol. Exercise workloads were determined by matching heart rate responses from each LBNP level. Heart rate and stroke volume (SV) were measured via Finometer. ECG, heat flux, skin temperature, galvanic skin response, and two-axis acceleration were obtained from an armband (SenseWear Pro2) and used to develop a machine-learning algorithm to predict changes in SV as an index of central blood volume under both conditions. The algorithm SV was retrospectively compared against Finometer SV. A model was developed to determine whether unknown data points could be correctly classified into these two conditions using leave-one-out cross-validation. Algorithm vs. Finometer SV values were strongly correlated for LBNP in individual subjects (mean r = 0.92; range 0.75-0.98), but only moderately correlated for exercise (mean r = 0.50; range -0.23-0.87). From the first level of LBNP/exercise, the machine-learning algorithm was able to distinguish between LBNP and exercise with high accuracy, sensitivity, and specificity (all ≥90%). In conclusion, a machine-learning algorithm developed from low-level physiological signals could reliably distinguish central hypovolemia from exercise, indicating that this device could provide battlefield remote triage capabilities. PMID:24408992

  11. Effects of CO2 pneumoperitoneum on blood flow vol-ume of abdominal organs of rabbits with controlled hem-orrhagic shock and liver impact injuries

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lian-yang; ZHAO Song; LI Yong; MA Xiao-lin

    2009-01-01

    Objective: To investigate the effects of CO2 pneumo-peritoneum on blood flow volume of abdominal organs of rabbits with controlled hemorrhagic shock model and liver impact injuries.Methods: After controlled hemorrhagic shock and liver impact injuries, the rabbit model was established. Eighteen rabbits subjected to hemorrhagic shock and liver impact inju-ries were divided into 3 groups randomly according to the volume of lost blood: light hemorrhagic shock (blood loss volume was 10%, 6 ml/kg), moderate hemorrhagic shock (20%, 12 ml/kg) and severe hemorrhagic shock (40%, 22 ml/kg). Intraabdominal pressures of CO2 pneumoperitoneum was 10 mmHg. Color-labeled microspheres were used to mea-sure the blood flow volume of the liver, kidney and stomach before pneumoperitoneum at 30 minutes and 2 hours after pneumoperitoneum and 30 minutes after deflation. And the mortality and hepatic traumatic condition of rabbits were recorded.Results: Of the 18 rabbits, there were 9 with liver impact injuries at Grade Ⅰ, 8 at Grade Ⅱ and Ⅰ at Grade Ⅲ (according to AIS-2005). The mortality rate in light hemorrhagic shock group was 33.33%, and that in moderate or severe hemor-rhagic shock group was 100% within 30 minutes and 2 hours after pneumoperitoneum, respectively. The blood flow vol-ume in the organs detected decreased at 30 minutes under pneumoperitoneum in light and moderate hemorrhagic shock groups. At the same time, the blood flow volume of the liver in moderate hemorrhagic shock group decreased more sig-nificantly than that in light hemorrhagic shock group.Conclusions: The blood flow volume of abdominal organs in rabbits is decreased obviously under CO2 pneumoperitoneum, with fairly high mortality rate. It is be-lieved that CO2 pneumoperitoneum should cautiously be used in abdominal injury accompanied with hemorrhagic shock, especially under non-resuscitation conditions.

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

    OpenAIRE

    Bernstein, Donald P.

    2010-01-01

    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 (&Omega...

  13. Initial study of 3D perfused blood volume imaging using 64-detector CT in hyperacute cerebral infarction

    International Nuclear Information System (INIS)

    Objective: To evaluate the value of three dimensional CT whole brain perfused blood volume (3D-PBV) based on CTA row data in hyperacute cerebral infarction. Methods: 38 patients with stroke within 12 hours performed plain CT and CTA scans. 3D software Neuro PBV was applied to process the CTA row data and 3D-PBV of brain was obtained. MR examinations were performed within 2 hours after CT scans. The numbers of ischemic lesions on plain CT, 3D-PBV and MRI-DWI were recorded. The volumes of ischemic lesions on 3D-PBV and MR -DWI were measured. Results: In 38 patients, the number of infarct lesion detected by MRI-DWI, PBV, and plain CT was 45, 41, and 16 respectively. Kappa test showed a substantial agreement (κ=0.78) between 3D-PBV and MRI-DWI in detecting ischemic lesions. The detectability of plain CT showed fair or slight agreements to 3D-PBV and MR-DWI (κ=0.24, 0.18, respectively). The lesion volumes did not differ on 3D-PBV and MR-DWI (t=7.249, P>0.05). Conclusion: 3D-PBV combined with CTA can detect ischemic lesion and evaluate perfusion. It had important value in diagnosing hyperacute cerebral infarction. (authors)

  14. Higher blood volumes improve the sensitivity of direct PCR diagnosis of blood stream tuberculosis among HIV-positive patients: an observation study

    OpenAIRE

    Bwanga, Freddie; Disqué, Claudia; Lorenz, Michael G.; Allerheiligen, Vera; Worodria, William; Luyombya, Allan; Najjingo, Irene; Weizenegger, Michael

    2015-01-01

    Background Blood stream tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB) is common among HIV-positive patients, turning rapidly fatal unless detected and treated promptly. Blood culture is currently the standard test for the detection of MTB in whole blood but results take weeks; patients deteriorate markedly and often die before a diagnosis of blood stream TB is made. Rapid molecular tests on whole blood, with potential for same day diagnosis of blood stream TB usually show low ...

  15. Imaging transient blood vessel fusion events in zebrafish by correlative volume electron microscopy.

    Directory of Open Access Journals (Sweden)

    Hannah E J Armer

    Full Text Available The study of biological processes has become increasingly reliant on obtaining high-resolution spatial and temporal data through imaging techniques. As researchers demand molecular resolution of cellular events in the context of whole organisms, correlation of non-invasive live-organism imaging with electron microscopy in complex three-dimensional samples becomes critical. The developing blood vessels of vertebrates form a highly complex network which cannot be imaged at high resolution using traditional methods. Here we show that the point of fusion between growing blood vessels of transgenic zebrafish, identified in live confocal microscopy, can subsequently be traced through the structure of the organism using Focused Ion Beam/Scanning Electron Microscopy (FIB/SEM and Serial Block Face/Scanning Electron Microscopy (SBF/SEM. The resulting data give unprecedented microanatomical detail of the zebrafish and, for the first time, allow visualization of the ultrastructure of a time-limited biological event within the context of a whole organism.

  16. Blood Pressure Quiz

    Science.gov (United States)

    ... page please turn Javascript on. Feature: High Blood Pressure Blood Pressure Quiz Past Issues / Fall 2011 Table of Contents ... About High Blood Pressure / Treatment: Types of Blood Pressure Medications / Blood Pressure Quiz Fall 2011 Issue: Volume 6 Number ...

  17. Dynamic contrast-enhanced MRI assessment of hyperemic fractional microvascular blood plasma volume in peripheral arterial disease: initial findings.

    Directory of Open Access Journals (Sweden)

    Bas Versluis

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

  18. 每搏量变异度与患者血容量变化的相关性%Correlation between stroke volume variation and blood volume

    Institute of Scientific and Technical Information of China (English)

    王合梅; 贾慧群; 雍芳芳; 李超; 王勇; 赵伟

    2010-01-01

    Objective To evaluate the correlation between stroke volume variation (SVV) and the blood volume. Methods Forty-eight ASA Ⅱ male patients, aged 50-60 yr, scheduled for elective radical operation for gastric cancer, were studied. Anesthesia was induced with fentanyl 4 μg/kg, propofol 2 mg/kg and cis-atracurium 0.15 mg/kg and maintained with inhalation of 2%-3% sevoflurane. 6% HES 130/0.4 was infused intravenously at a rate of 0.67 ml· kg - 1 · min - 1 30 min after induction. SVV,cardiac output (CO),SV and cardiac index (CI) were monitored and recorded using the FloTrac/Vigileo (Edwards Lifesciences, USA) system before HES was infused and when the dose of HES reached 2, 4, 6, 8, 10, 12, 14, 16 and 18 ml/kg. CVP was also recorded at the corresponding time points. Spearman's rank sum correlation coefficient was used to analyze the data. Results Correlation coefficients between the amount of HES infused and CO, SV, CI or CVP were rSVV = - 0.91 ± 0.06,rCO = 0.83 ± 0.04, rSV = 0.86 ± 0.09, rCI = 0.86 ± 0.09 and rCVP = 0.90 ± 0.03. Among the 5 correlation coefficients, rSVV was the highest, rCVP was significantly higher than rCO, rSV and rCI (P < 0.05), and there was no significant difference among rCO, rSV and r CI (P > 0. 05). Conclusion SVV is highly correlated with the blood volume and can be used to guide volume therapy.%目的 评价每搏量变异度(SVV)与患者血容量变化的相关性.方法 择期胃癌根治术男性患者48例,年龄50~60岁,ASA分级Ⅱ级.麻醉诱导后30 min静脉输注6%羟乙基淀粉130/0.40.67 ml·kg-1·min-1,分别于输注前、输注羟乙基淀粉剂量达2、4、6、8、10、12、14、16、18 ml/kg时,记录SVV、CO、SV、CI和CVP.SVV、CO、SV、CI和CVP与羟乙基淀粉输注量行Spearman等级相关分析.结果 SVV、CO、SV、CI和CVP与羟乙基淀粉输注量之间的相关系数分别为:rSVV=-0.91±0.06,rCO=0.83±0.04,rSV=0.86±0.09,rCI=0.86±0.09,rCVP=0.90±0.03.5个相关系数中,rSVV最高,r

  19. Factors affecting the lung perfused blood volume in patients with intrapulmonary clots after anti-coagulation therapy

    International Nuclear Information System (INIS)

    Highlights: • Dual-energy CT can provide morphological and functional lung images in the same examination. • The subsequent dual-energy CT demonstrates the increased whole lung perfused blood volume (V120) despite the residual intrapulmonary clots after treatment in one examination. • The increased whole lung perfusion (V120) and a decreased low perfusion volume (V5) result in the improvement in the low perfusion rate (%V5) in the patients with acute pulmonary embolism after treatment. - Abstract: Objectives: Factors affecting the improvement in the lung perfused blood volume (LPBV) were evaluated based on the presence of intrapulmonary clots (IPCs) after anti-coagulation therapy using 64-slice dual-energy CT. Materials and methods: 96 patients exhibiting venous thromboembolism underwent initial and repeated LPBV examinations between December 2008 and July 2014. Fifteen patients were excluded due to pulmonary comorbidities, and a total of 81 patients were included in this study. Acute pulmonary embolism (PE) was diagnosed in 46 of the patients (56.7%). LPBV images were three-dimensionally reconstructed with two threshold ranges: 1–120 HU (V120) and 1–5 HU (V5), and the relative value of V5 per V120 expressed as %V5. These values were subsequently compared with indicators of the severity of PE, such as the D-dimer level, heart rate and CT measurements. This study was approved by the local ethics committee. Results: In patients with IPCs, the D-dimer, V5 and %V5values were significantly larger (p ≤ 0.01) in the initial LPBV, although these differences disappeared in subsequent LPBV after treatment. The right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio and %V5 values were also significantly reduced, whereas the V5 value did not significantly decrease (p = 0.07), but V120 value significantly increased (p < 0.001) after treatment. However, in patients with IPCs the change rate in %V5 [(subsequent-initial)/initial %V5] showed a

  20. Factors affecting the lung perfused blood volume in patients with intrapulmonary clots after anti-coagulation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Masuda, Yu [4th Grade of 6-year Medicine Doctor Program, Department of Medicine, Yamaguchi University Faculty of Medicine and Health Sciences 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi; Nakao, Sei [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Kido, Shoji [Computer-aided Diagnosis and Biomedical Imaging Research Biomedical Engineering, Applied Medical Engineering Science Graduate School of Medicine, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

    2015-08-15

    Highlights: • Dual-energy CT can provide morphological and functional lung images in the same examination. • The subsequent dual-energy CT demonstrates the increased whole lung perfused blood volume (V{sub 120}) despite the residual intrapulmonary clots after treatment in one examination. • The increased whole lung perfusion (V{sub 120}) and a decreased low perfusion volume (V{sub 5}) result in the improvement in the low perfusion rate (%V{sub 5}) in the patients with acute pulmonary embolism after treatment. - Abstract: Objectives: Factors affecting the improvement in the lung perfused blood volume (LPBV) were evaluated based on the presence of intrapulmonary clots (IPCs) after anti-coagulation therapy using 64-slice dual-energy CT. Materials and methods: 96 patients exhibiting venous thromboembolism underwent initial and repeated LPBV examinations between December 2008 and July 2014. Fifteen patients were excluded due to pulmonary comorbidities, and a total of 81 patients were included in this study. Acute pulmonary embolism (PE) was diagnosed in 46 of the patients (56.7%). LPBV images were three-dimensionally reconstructed with two threshold ranges: 1–120 HU (V{sub 120}) and 1–5 HU (V{sub 5}), and the relative value of V{sub 5} per V{sub 120} expressed as %V{sub 5}. These values were subsequently compared with indicators of the severity of PE, such as the D-dimer level, heart rate and CT measurements. This study was approved by the local ethics committee. Results: In patients with IPCs, the D-dimer, V{sub 5} and %V{sub 5}values were significantly larger (p ≤ 0.01) in the initial LPBV, although these differences disappeared in subsequent LPBV after treatment. The right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio and %V{sub 5} values were also significantly reduced, whereas the V{sub 5} value did not significantly decrease (p = 0.07), but V{sub 120} value significantly increased (p < 0.001) after treatment. However, in

  1. Alginate/PEG based microcarriers with cleavable crosslinkage for expansion and non-invasive harvest of human umbilical cord blood mesenchymal stem cells.

    Science.gov (United States)

    Li, Chunge; Qian, Yufeng; Zhao, Shuang; Yin, Yuji; Li, Junjie

    2016-07-01

    Porous microcarriers are increasingly used to expand and harvest stem cells. Generally, the cells are harvested via proteolytic enzyme treatment, which always leads to damages to stem cells. To address this disadvantage, a series of alginate/PEG (AL/PEG) semi-interpenetrating network microcarriers are prepared in this study. In this AL/PEG system, the chemically cross-linked alginate networks are formed via the reaction between carboxylic acid group of alginate and di-terminated amine groups of cystamine. PEG is introduced to modulate the degradation of microcarriers, which does not participate in this cross-linked reaction, while it interpenetrates in alginate network via physical interactions. In addition, chitosan are coated on the surface of AL/PEG to improve the mechanical strength via the electrostatic interactions. Biocompatible fibronectin are also coated on these microcarriers to modulate the biological behaviors of cells seeded in microcarriers. Results suggest that the size of AL/PEG microcarriers can be modulated via adjusting the contents and molecular weight of PEG. Moreover, the microcarriers are designed to be degraded with cleavage of disulfide crosslinkage. By changing the type and concentration of reductant, the ratio of AL to PEG, and the magnitude of chitosan coating, the degradation ability of AL/PEG microcarriers can be well controlled. In addition, AL/PEG microcarriers can support the attachment and proliferation of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs). More importantly, the expanded hUCB-MSCs can be detached from microcarriers after addition of reductant, which indeed reduce the cell damage caused by proteolytic enzyme treatment. Therefore, it is convinced that AL/PEG based microcarriers will be a promising candidate for large-scale expansion of hUCB-MSCs. PMID:27127027

  2. Blood characteristics, tracheal volume and heart mass of burrowing owls (Athene cunicularia) and bobwhite (Colinus virginianus).

    Science.gov (United States)

    Boggs, D F; Birchard, G F; Kilgore, D L

    1983-01-01

    1. Measurements of certain hematological and morphological characteristics were made in burrowing owls and bobwhite in search of features that could be associated with the previously described ventilatory adaptations of the burrowing owl to hypoxia and hypercarbia. 2. Values for burrowing owls and bobwhite, respectively, were: P50 = 44.9, 46.0 torr; Hct = 36.6, 38.8 vol%, Hb = 12, 12.3 (g/100 ml); RBC = 2.72 X 10(6), 3.02 X 10(6); log P50/pH = -0.412, -0.485; delta log PCO2/delta pH = -1.39, -1.585. 3. The owls had greater heart weights and smaller tracheal volumes than the bobwhite or the predicted value. 4. No hematological characteristics of the burrowing bird distinguish it from the non-burrowing bird. PMID:6132713

  3. Real-time contrast-enhanced ultrasound determination of microvascular blood volume in abdominal subcutaneous adipose tissue in man. Evidence for adipose tissue capillary recruitment

    DEFF Research Database (Denmark)

    Tobin, L; Simonsen, L; Bülow, J

    2010-01-01

    The adipose tissue metabolism is dependent on its blood perfusion. During lipid mobilization e.g. during exercise and during lipid deposition e.g. postprandial, adipose tissue blood flow is increased. This increase in blood flow may involve capillary recruitment in the tissue. We investigated the...... basic and postprandial microvascular volume in adipose tissue using real-time contrast-enhanced ultrasound (CEU) imaging in healthy normal weight subjects. In nine subjects, CEU was performed in abdominal subcutaneous adipose tissue and in the underlying skeletal muscle after a bolus injection of...... ultrasound contrast agent to establish the reproducibility of the technique. In nine subjects, the effect of an oral glucose load on blood flow and microvascular volume was measured in abdominal subcutaneous adipose tissue and forearm skeletal muscle. ¹³³Xe washout and venous occlusion strain...

  4. Influence of Resting Venous Blood Volume Fraction on Dynamic Causal Modeling and System Identifiability.

    Science.gov (United States)

    Hu, Zhenghui; Ni, Pengyu; Wan, Qun; Zhang, Yan; Shi, Pengcheng; Lin, Qiang

    2016-01-01

    Changes in BOLD signals are sensitive to the regional blood content associated with the vasculature, which is known as V0 in hemodynamic models. In previous studies involving dynamic causal modeling (DCM) which embodies the hemodynamic model to invert the functional magnetic resonance imaging signals into neuronal activity, V0 was arbitrarily set to a physiolog-ically plausible value to overcome the ill-posedness of the inverse problem. It is interesting to investigate how the V0 value influences DCM. In this study we addressed this issue by using both synthetic and real experiments. The results show that the ability of DCM analysis to reveal information about brain causality depends critically on the assumed V0 value used in the analysis procedure. The choice of V0 value not only directly affects the strength of system connections, but more importantly also affects the inferences about the network architecture. Our analyses speak to a possible refinement of how the hemody-namic process is parameterized (i.e., by making V0 a free parameter); however, the conditional dependencies induced by a more complex model may create more problems than they solve. Obtaining more realistic V0 information in DCM can improve the identifiability of the system and would provide more reliable inferences about the properties of brain connectivity. PMID:27389074

  5. Blood volume-monitored regulation of ultrafiltration in fluid-overloaded hemodialysis patients: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Hecking Manfred

    2012-06-01

    Full Text Available Abstract Background Data generated with the body composition monitor (BCM, Fresenius show, based on bioimpedance technology, that chronic fluid overload in hemodialysis patients is associated with poor survival. However, removing excess fluid by lowering dry weight can be accompanied by intradialytic and postdialytic complications. Here, we aim at testing the hypothesis that, in comparison to conventional hemodialysis, blood volume-monitored regulation of ultrafiltration and dialysate conductivity (UCR and/or regulation of ultrafiltration and temperature (UTR will decrease complications when ultrafiltration volumes are systematically increased in fluid-overloaded hemodialysis patients. Methods/design BCM measurements yield results on fluid overload (in liters, relative to extracellular water (ECW. In this prospective, multicenter, triple-arm, parallel-group, crossover, randomized, controlled clinical trial, we use BCM measurements, routinely introduced in our three maintenance hemodialysis centers shortly prior to the start of the study, to recruit sixty hemodialysis patients with fluid overload (defined as ≥15% ECW. Patients are randomized 1:1:1 into UCR, UTR and conventional hemodialysis groups. BCM-determined, ‘final’ dry weight is set to normohydration weight −7% of ECW postdialysis, and reached by reducing the previous dry weight, in steps of 0.1 kg per 10 kg body weight, during 12 hemodialysis sessions (one study phase. In case of intradialytic complications, dry weight reduction is decreased, according to a prespecified algorithm. A comparison of intra- and post-dialytic complications among study groups constitutes the primary endpoint. In addition, we will assess relative weight reduction, changes in residual renal function, quality of life measures, and predialysis levels of various laboratory parameters including C-reactive protein, troponin T, and N-terminal pro-B-type natriuretic peptide, before and after the first study

  6. Arterial pressure variations as parameters of brain perfusion in response to central blood volume depletion and repletion

    Directory of Open Access Journals (Sweden)

    Anne-SophieG.T.Bronzwaer

    2014-04-01

    Full Text Available Rationale:\tA critical reduction in central blood volume (CBV is often characterized by hemodynamic instability. Restoration of a volume deficit may be established by goal-directed fluid therapy guided by respiration-related variation in systolic- and pulse pressure (SPV and PPV. Stroke volume index (SVI serves as a surrogate end-point of a fluid challenge but tissue perfusion itself has not been addressed. Objective: To delineate the relationship between arterial pressure variations, SVI and regional brain perfusion during CBV depletion and repletion in spontaneously breathing volunteers. Methods: This study quantified in 14 healthy subjects (11 male the effects of CBV depletion (by 30 and 70 degrees passive head-up tilt (HUT and a fluid challenge (by tilt back on CBV (thoracic admittance, mean middle cerebral artery (MCA blood flow velocity (Vmean, SVI, cardiac index (CI , PPV and SPV. Results: PPV (103±89%, p< 0.05 and SPV (136±117%, p< 0.05 increased with progression of central hypovolemia manifested by a reduction in thoracic admittance (11±5%, p< 0.001, SVI (28±6%, p< 0.001, CI (6±8%, p< 0.001 and MCAVmean (17±7%, p< 0.05 but not in arterial pressure. The reduction in MCAVmean correlated to the fall in SVI (R2=0.52, p< 0.0001 and inversely to PPV and SPV (R2=0.46 (p< 0.0001 and R2=0.45 (p< 0.0001, respectively. PPV and SPV predicted a ≥15% reduction in MCAVmean and SVI with comparable sensitivity (67%/ 67% vs. 63%/ 68% respectively and specificity (89%/94% vs. 89%/94%, respectively. A rapid fluid challenge by tilt-back restored all parameters to baseline values within one minute. Conclusion: In spontaneously breathing subjects, a reduction in MCAVmean was related to an increase in PPV and SPV during graded CBV depletion and repletion. Specifically, PPV and SPV predicted changes in both SVI and MCAVmean with comparable sensitivity and specificity, however the predictive value is limited in spontaneously breathing subjects.

  7. The Pilot Study of Evaluating Fluctuation in the Blood Flow Volume of the Radial Artery, a Site for Traditional Pulse Diagnosis

    Directory of Open Access Journals (Sweden)

    Masashi Watanabe

    2016-05-01

    Full Text Available Background: Radial artery (RA pulse diagnosis has been used in traditional Asian medicine. Blood pressure (BP and pulse rate related to heart rate variability (HRV can be monitored via the RA. The fluctuation in these parameters has been assessed using fast Fourier transform (FFT analytical methods that calculate power spectra. Methods: We measured blood flow volume (Volume in the RA and evaluated its fluctuations. Normal participants (n = 34 were enrolled. We measured the hemodynamics of the right RA for approximately 50 s using ultrasonography. Results: The parameters showed the center frequency (CF of the power spectrum at low frequency (LF and high frequency (HF. More than one spectral component indicated that there were fluctuations. The CF at LF for Volume was significantly different from that for vessel diameter (VD; however, it was significantly correlated with blood flow velocity (Velocity. On the other hand, the CF at HF for Volume was significantly different from that for Velocity; however, it was significantly correlated with VD. Conclusion: It is suggested that fluctuation in the Volume at LF of RA is influenced by the fluctuation in Velocity; on the other hand, fluctuation in the Volume at HF is influenced by the fluctuation in VD.

  8. Curvas pressão-volume e expansão foliar em cultivares de algodoeiro submetidos à défcit hídrico Pressure-volume curves and leaf expansion in cotton cultivars under water deficit

    Directory of Open Access Journals (Sweden)

    Celso Jamil Marur

    1999-07-01

    Full Text Available Foi avaliado o comportamento de dois cultivares de algodoeiro em resposta ao déficit hídrico, utilizando-se a expansão foliar como parâmetro discriminatório, bem como a metodologia das curvas pressão-volume para comparar suas habilidades com relação ao ajustamento osmótico. Nos tratamentos estressados, os valores dos Ys em plena turgescência e em turgescência zero obtidos para 'IAC 13-1' foram 0,1 MPa menores do que os obtidos para 'IAC 20'. O ajustamento osmótico em plena turgescência foi de 0.15 e 0.03 MPa, e em turgescência zero foi de 0.18 e 0.07 MPa, respectivamente para os dois cultivares. Os menores valores obtidos para o cultivar 'IAC 13-1' parecem indicar que seus tecidos suportam o estresse por um tempo maior antes das células atingirem o estado de plasmólise. Os valores do módulo volumétrico de elasticidade aumentaram quando os dois cultivares foram submetidos ao estresse hídrico, sendo que o cultivar 'IAC 13-1' parece apresentar paredes celulares com maior elasticidade. Os valores de Ya, antes do amanhecer, em que ocorreu a paralização do crescimento da folha foram -1,04 MPa e -0,98 MPa para os cultivares 'IAC 13-1' e 'IAC 20', respectivamente, mas não detectou-se diferenças significativas entre os dois cultivares.The response of two cotton cultivars to water deficit was studied using leaf expansion and pressure-volume curves method to compare their ability in relation to osmotic adjustment. The osmotic potential at full saturation and at the turgor loss point, for 'IAC 13-1', were 0.1 MPa lower than for `IAC 20' under later stress. Osmotic adjustment at full saturation was 0.15 and 0.03 MPa, and at turgor loss point was 0.18 and 0.07 MPa for 'IAC 13-1'and 'IAC 20', respectively. The low osmotic potential values observed for 'IAC 13-1' suggests that the tissues support water deficit longer, before cells reach plasmolysis. The values for bulk modulus of elasticity were higher when both cultivars were under water

  9. Volume Tracking: A new method for quantitative assessment and visualization of intracardiac blood flow from three-dimensional, time-resolved, three-component magnetic resonance velocity mapping

    Directory of Open Access Journals (Sweden)

    Arheden Håkan

    2011-04-01

    Full Text Available Abstract Background Functional and morphological changes of the heart influence blood flow patterns. Therefore, flow patterns may carry diagnostic and prognostic information. Three-dimensional, time-resolved, three-directional phase contrast cardiovascular magnetic resonance (4D PC-CMR can image flow patterns with unique detail, and using new flow visualization methods may lead to new insights. The aim of this study is to present and validate a novel visualization method with a quantitative potential for blood flow from 4D PC-CMR, called Volume Tracking, and investigate if Volume Tracking complements particle tracing, the most common visualization method used today. Methods Eight healthy volunteers and one patient with a large apical left ventricular aneurysm underwent 4D PC-CMR flow imaging of the whole heart. Volume Tracking and particle tracing visualizations were compared visually side-by-side in a visualization software package. To validate Volume Tracking, the number of particle traces that agreed with the Volume Tracking visualizations was counted and expressed as a percentage of total released particles in mid-diastole and end-diastole respectively. Two independent observers described blood flow patterns in the left ventricle using Volume Tracking visualizations. Results Volume Tracking was feasible in all eight healthy volunteers and in the patient. Visually, Volume Tracking and particle tracing are complementary methods, showing different aspects of the flow. When validated against particle tracing, on average 90.5% and 87.8% of the particles agreed with the Volume Tracking surface in mid-diastole and end-diastole respectively. Inflow patterns in the left ventricle varied between the subjects, with excellent agreement between observers. The left ventricular inflow pattern in the patient differed from the healthy subjects. Conclusion Volume Tracking is a new visualization method for blood flow measured by 4D PC-CMR. Volume Tracking

  10. Smart fast blood counting of trace volumes of body fluids from various mammalian species using a compact custom-built microscope cytometer (Conference Presentation)

    Science.gov (United States)

    Smith, Zachary J.; Gao, Tingjuan; Lin, Tzu-Yin; Carrade-Holt, Danielle; Lane, Stephen M.; Matthews, Dennis L.; Dwyre, Denis M.; Wachsmann-Hogiu, Sebastian

    2016-03-01

    Cell counting in human body fluids such as blood, urine, and CSF is a critical step in the diagnostic process for many diseases. Current automated methods for cell counting are based on flow cytometry systems. However, these automated methods are bulky, costly, require significant user expertise, and are not well suited to counting cells in fluids other than blood. Therefore, their use is limited to large central laboratories that process enough volume of blood to recoup the significant capital investment these instruments require. We present in this talk a combination of a (1) low-cost microscope system, (2) simple sample preparation method, and (3) fully automated analysis designed for providing cell counts in blood and body fluids. We show results on both humans and companion and farm animals, showing that accurate red cell, white cell, and platelet counts, as well as hemoglobin concentration, can be accurately obtained in blood, as well as a 3-part white cell differential in human samples. We can also accurately count red and white cells in body fluids with a limit of detection ~3 orders of magnitude smaller than current automated instruments. This method uses less than 1 microliter of blood, and less than 5 microliters of body fluids to make its measurements, making it highly compatible with finger-stick style collections, as well as appropriate for small animals such as laboratory mice where larger volume blood collections are dangerous to the animal's health.

  11. Densities, excess molar volume, isothermal compressibility, and isobaric expansivity of (dimethyl carbonate + n-hexane) systems at temperatures (293.15 to 313.15) K and pressures from 0.1 MPa up to 40 MPa

    International Nuclear Information System (INIS)

    The densities of dimethyl carbonate, n-hexane and their mixtures were measured for 12 compositions at five different temperatures varying from (293.15 to 313.15) K and over the pressure range of (0.1 to 40) MPa. The densities of pure substances and their mixtures at atmospheric pressure were measured by a vibrating-tube densimeter. The densities at high pressures were measured by a variable-volume autoclave and precise analytical balance. The excess molar volume, isothermal compressibility, and isobaric expansivity were derived from the experimental densities.

  12. Cleavage of endogenous γENaC and elevated abundance of αENaC are associated with increased Na+ transport in response to apical fluid volume expansion in human H441 airway epithelial cells

    OpenAIRE

    Tan, Chong D.; Selvanathar, Indusha A.; Baines, Deborah L.

    2011-01-01

    Using human H441 airway epithelial cells cultured at air–liquid interface (ALI), we have uniquely correlated the functional response to apical fluid volume expansion with the abundance and cleavage of endogenous α- and γENaC proteins in the apical membrane. Monolayers cultured at ALI rapidly elevated I sc when inserted into fluid-filled Ussing chambers. The increase in I sc was not significantly augmented by the apical addition of trypsin, and elevation was abolished by the protease inhibitor...

  13. Blood pressure levels, left ventricular mass and function are correlated with left atrial volume in mild to moderate hypertensive patients.

    Science.gov (United States)

    Milan, A; Caserta, M A; Dematteis, A; Naso, D; Pertusio, A; Magnino, C; Puglisi, E; Rabbia, F; Pandian, N G; Mulatero, P; Veglio, F

    2009-11-01

    Arterial hypertension is associated with an increased risk of atrial fibrillation (AF), and leads to a pronounced increase in morbidity and mortality. Left atrial volume (LAV) is an important prognostic marker in the older populations. The aim of our study was to identify the clinical and echocardiographic determinants of LAV in middle-aged (<70 years old) essential hypertensive patients.We evaluated cardiac structure and function in 458 patients, 394 treated and untreated mild to moderate essential hypertensives patients (mean+/-s.d. age 48.4+/-11.1 years) with no associated clinical condition and 64 normotensive control participants (age 45.7+/-12.8 years; P=0.12). A multivariate analysis was performed to calculate the relative weight of each of the variables considered able to predict LAV. The LAV index (LAVi) was significantly increased in the essential hypertensive group vs the control group and was significantly dependent on blood pressure levels (SBP and DBP, P<0.05 for both) and body mass index (BMI) (P<0.0001). Considering the left ventricular (LV) variables, the LV mass index (LVMI) (R(2)=0.19, P<0.001) and LAV were increased in essential hypertensive patients with left ventricular hypertrophy (LVH), and patients with enlarged LAV showed lower systolic and diastolic function and an increased LVMI. The LAVi is dependent on blood pressure levels and anthropometric variables (age and BMI). Further structural (LVMI) and functional (systolic and diastolic) variables are related to the LAVi; LVMI is the most important variable associated with LAV in mild to moderate essential hypertensive adult patients. These findings highlight the importance of left atrium evaluation in adult, relatively young, essential hypertensive patients. PMID:19262581

  14. Effect of saline infusion for the maintenance of blood volume on pulmonary gas exchange during temporary abdominal aortic occlusion

    Directory of Open Access Journals (Sweden)

    F.F. Amorim

    2007-03-01

    Full Text Available We analyzed the effects of saline infusion for the maintenance of blood volume on pulmonary gas exchange in ischemia-reperfusion syndrome during temporary abdominal aortic occlusion in dogs. We studied 20 adult mongrel dogs weighing 12 to 23 kg divided into two groups: ischemia-reperfusion group (IRG, N = 10 and IRG submitted to saline infusion for the maintenance of mean pulmonary arterial wedge pressure between 10 and 20 mmHg (IRG-SS, N = 10. All animals were anesthetized and maintained on spontaneous ventilation. After obtaining baseline measurements, occlusion of the supraceliac aorta was performed by the inflation of a Fogarty catheter. After 60 min of ischemia, the balloon was deflated and the animals were observed for another 60 min of reperfusion. The measurements were made at 10 and 45 min of ischemia, and 5, 30, and 60 min of reperfusion. Pulmonary gas exchange was impaired in the IRG-SS group as demonstrated by the increase of the alveolar-arterial oxygen difference (21 ± 14 in IRG-SS vs 11 ± 8 in IRG after 60 min of reperfusion, P = 0.004 in IRG-SS in relation to baseline values and the decrease of oxygen partial pressure in arterial blood (58 ± 15 in IRG-SS vs 76 ± 15 in IRG after 60 min of reperfusion, P = 0.001 in IRG-SS in relation to baseline values, which was correlated with the highest degree of pulmonary edema in morphometric analysis (0.16 ± 0.06 in IRG-SS vs 0.09 ± 0.04 in IRG, P = 0.03 between groups. There was also a smaller ventilatory compensation of metabolic acidosis after the reperfusion. We conclude that infusion of normal saline worsened the gas exchange induced by pulmonary reperfusion injury in this experimental model.

  15. Evaluation of the cardiac performance in patients with coronary arterty disease by the pulmonary blood volume change in exercise testing

    International Nuclear Information System (INIS)

    Evaluation of the cardiac performance was studied by the change of the pulmonary blood volume (PBV) during the exercise testing in 17 normal subjects (group N), 18 patients with angina pectoris (group A) and 25 with both old myocardial infarction and angina pectoris (group M). The exercise testing was performed by bicycle ergometer in supine position. Blood pressure, heart rate, cardiac output measured by dye dilution method, left ventricular ejection fraction (EF) by multi-gate method, pulmonary artery pressure by Swan-Ganz catheter and PBV was measured during exercise. PBV was estimated by the radioactivity of the systemically administered Tc-99m labeled RBC in the lung field. ROI was adjusted over the right upper and lower lung field. And also the effect of the nitroglycerin was examined. In the result, (1) EF at the peak exercise increased in group N but decreased in Groups A and M. (2) Increased pulmonary artery diastolic pressure at the peak exercise (PAd at exercise) was remarkably higher in groups A and M than group M. (3) PBV was unchanged in group N; however, increased 9.6% in group A and 10.9% in group M. (4) Increased rate of PBV revealed good correlation with ΔEF (r=-0.68, p<0.01) and PAd at exercise (r=0.83, p<0.01), and was considered as the pulmonary congestion due to left ventricular dysfunction. (5) After the sublingual administration of nitroglycerin, the increased PAd and PBV at the peak exercise was suppressed. Particularly, it was remarkable in group A. Thus it was concluded that the noninvasive measurement of PBV during exercise could suggest the extent of the pulmonary congestion and was very useful for evaluation of the cardiac performance in coronary artery disease. (author)

  16. Blood-retinal barrier glycerol permeability in diabetic macular edema and healthy eyes: estimations from macular volume changes after peroral glycerol

    DEFF Research Database (Denmark)

    Thornit, Dorte Nellemann; Vinten, Carl Martin; Sander, Birgit;

    2010-01-01

    PURPOSE: To compare the changes in macular volume (MV) between healthy subjects and patients with diabetic macular edema (DME) after an osmotic load and to determine the glycerol permeability (P(gly)) of the blood-retinal barrier (BRB). METHODS: In this unmasked study, 13 patients with DME and 5...

  17. Validation of quantitative estimation of tissue oxygen extraction fraction and deoxygenated blood volume fraction in phantom and in vivo experiments by using MRI.

    Science.gov (United States)

    Sedlacik, Jan; Reichenbach, Jürgen R

    2010-04-01

    The blood oxygenation level dependent signal of cerebral tissue can be theoretically derived using a network model formed by randomly oriented infinitely long cylinders. The validation of this model by phantom and in vivo experiments is still an object of research. A network phantom was constructed of solid polypropylene strings immersed in silicone oil, which essentially eliminated the effect of spin diffusion. The volume fraction and magnetic property of the string network was predetermined by independent methods. Ten healthy volunteers were measured for in vivo demonstration. The gradient echo sampled spin echo signal was evaluated with the cylinder network model. We found a strong interdependency between the two network characterizing parameters deoxygenated blood volume and oxygen extraction fraction. Here, different sets of deoxygenated blood volume/oxygen extraction fraction values were able to describe the measured signal equally well. However, by setting one parameter constant to a predetermined value, reasonable estimates of the other parameter were obtained. The same behavior was found for the in vivo demonstration. The signal theory of the cylinder network was validated by a well-characterized phantom. However, the found interdependency that was found between deoxygenated blood volume and oxygen extraction fraction requires an independent estimation of one variable to determine reliable values of the other parameter. PMID:20373392

  18. The evolution of the cerebral blood volume abnormality in patients with ischemic stroke: a CT perfusion study

    Energy Technology Data Exchange (ETDEWEB)

    D' Esterre, Christopher D.; Lee, Ting Yim (Lawson Health Research Inst., London (Canada); Robarts Research Inst., London (Canada)), email: tlee@robarts.ca; Aviv, Richard I. (Sunnybrook Health Sciences Centre, Toronto (Canada))

    2012-05-15

    Background: Accurate identification of the acute infarct core abnormality is important for guiding acute stroke treatment. Abnormality volumes from diffusion-weighted MRI (DWI) and CT perfusion (CTP)-cerebral blood volume (CBV) are highly correlated. DWI lesions have been shown to be reversible at 24 h. Purpose: To examine the temporal profile of the CT perfusion (CTP)-derived CBV abnormality out to 7 days post ischemic stroke. Material and Methods: Twenty-six patients were included. Group A (n = 13) underwent a noncontrast CT (NCCT), CTP/CT angiography (CTA) within 6 h of stroke onset, CTP/CTA at 24 h, and CTP/NCCT at 5-7 days post stroke. Group B (n = 13) underwent a NCCT, CTP/CTA within 6 h of stroke onset, and NCCT at 5-7 days. Recanalization status was established in all patients. For both groups, infarct volumes were traced on 5-7 day NCCT images and superimposed onto all CTP-CBV functional maps to determine CBV. Group B (n = 13) admission images were used to define CBV infarct thresholds for gray and white matter. CBV-lesion overestimation was determined for Group A using the thresholds from Group B. Results: CBV (ml x 100g- 1; mean +- stdev) for gray/white matter, within confirmed infarcted regions (CBVI) at admission, 24 h, and 5-7 days were 1.82 +- 0.56, 1.56 +- 0.42, 1.75 +- 0.31, and 1.38 +- 0.65, 1.13 +- 0.31, 1.32 +- 0.44, respectively, when averaged over all patients (P > 0.05). Four patients had tissue time-density curves from ischemic lesions (TDCi) with an incomplete contrast medium wash-out phase (truncation) at admission and/or 24 h. Compared to admission, gray matter CBVI was higher at 5-7 days for patients with TDCi truncation (P < 0.05). There were no significant CBVI increases for the eight patients without truncation (P > 0.05). Over-estimation of acute CBV lesion was present in 3/4 (75%) and 1/9 (11%) of patients with/without TDCi truncation, respectively. Conclusion: CTP-derived CBV lesion reversal is associated with TDCi truncation

  19. The safest parameters for FUS-induced blood-brain barrier opening without effects on the opening volume

    Science.gov (United States)

    Tung, Yao-Sheng; Olumolade, Yemi; Wang, Shutao; Wu, Shih-Ying; Konofagou, Elisa E.

    2012-11-01

    Acoustic cavitation has been identified as the main physical mechanism for the focused ultrasound (FUS) induced blood-brain barrier (BBB) opening. In this paper, the mechanism of stable cavitation (SC) and inertial cavitation (IC) responsible for BBB opening was investigated. Thirty-three (n=33) mice were intravenously injected with bubbles of 4-5 μm in diameter. The right hippocampus was then sonicated using focused 1.5-MHz ultrasound and three different studies were carried out. First, pulse lengths (PLs) of 0.1, 0.5, 2, and 5 ms at 0.18- MPa peak rarefactional pressure with 5-Hz pulse repetition frequency (PRF) and 5-minute duration were used to identify the threshold of PL using SC. Second, the effects of the duty cycle and exposure time were investigated. Third, the BBB opening size was compared between the SC and the IC. In the case of IC-induced BBB opening, a burst sequence (3-cycles PL; 5-Hz burst repetition frequency (BRF); 30 s duration) at 0.45 MPa was applied. Passive cavitation detection was performed with each sonication to detect whether a broadband response was obtained, i.e., if IC occurred, during BBB opening. The properties of BBB opening were measured through MRI. The threshold of PL for BBB opening was identified between 0.1 and 0.5 ms using SC, but the BBB can be opened in few cycles using IC. The BBB opening volume and normalized intensity increased with the PL, but reached saturation when the PL was above 2 ms. Once the PL threshold was reached, the same exposure time induced a similar BBB opening volume, but longer sonication duration induced higher MR intensity. The duty cycle was found not to play an important role on the BBB opening. Comparable BBB opening volume (20-25 mm3) could be reached between long PL (7500 cycles, i.e., 5 ms) at 0.18 MPa and 3 cycles at 0.45 MPa. 3-kDa fluorescently tagged dextran may be able to diffuse to the parenchyma after IC-induced BBB opening at 0.45 MPa but not after SC-induced BBB opening at 0.18 MPa.

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

    International Nuclear Information System (INIS)

    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)

  1. Non-invasive estimation of the human pulmonary blood volume with gamma camera and RI-angiocardiography

    International Nuclear Information System (INIS)

    A new, non-invasive method for the estimation of the human pulmonary blood volume (PBV), existing between the pulmonary artery bifurcation (PAB) and the left atrium (LA), has been developed in this laboratory, in the form of PBV = PPT sub(RCG) x 0.77 x CO, equation (6), given in Appendix. This was an extension of the classical Stewart-Hamilton method of indicator dilution, applied to radioisotope angiocardiography. Using a gamma-camera, the radio-isotope (99 m Tc-albumin) dilution curves were recorded externally at the region of PAB, LA and LV (left ventricle), among other things, in human subjects in supine position. The mean transit time (MTT) was determined for each region, and the difference in MTT, e.g., ΔMTT sub(PAB-LA), was measured. We calculated PBV between PAB and LA as PBV = ΔMTT sub(PAB-LA) x CO, equation (1) given in Appendix. Empirical time relations between ΔMTT sub(PAB-LA) and PPT sub(RCG) were examined in mechanical models and human subjects, through several steps represented by equations (2) to (5), given in Appendix, and our tentatively final formula was equation (6). The values of PBV estimated in this way were in good agreement with those of PBV measured invasively in the past, using two injection sites (PA and LA) and one sampling site (artery). (author)

  2. Perfusion computed tomography of intracranial meningiomas: In vivo correlation of cerebral blood volume and vascular permeability

    Science.gov (United States)

    Granata, Francesca; Morabito, Rosa; Alafaci, Concetta; Barresi, Valeria; Tomasello, Francesco; Vinci, Sergio; Calamuneri, Alessandro; Grasso, Giovanni; Salpietro, Francesco Maria; Longo, Marcello

    2015-01-01

    Background A noninvasive method to predict the grade of a meningioma would be desirable since it would anticipate information about tumour nature, recurrence and improve tumour management and outcomes. The aim of the present study was to assess the ability of perfusion computed tomography (PCT) technique in predicting the meningioma grade before surgery. Data from PCT, such as cerebral blood volume (CBV) and permeability surface (PS), were correlated with immunohistolopathological information. Methods Twenty-three patients with a diagnosis of intracranial meningioma underwent PCT for pre-surgical evaluation of CBV and PS. During surgery, samples from the centre and periphery of the tumour were obtained. Two correspondent regions of interest (ROIs) were drawn on CBV and PS maps. Central and peripheral CBV and PS mean values were calculated. PCT parameters were correlated to CD-34 and endoglin. Results There was a positive correlation between PS and CD-34. No correlation was found between PS values and endoglin, CBV values and CD-34 and endoglin values. Conclusion Our findings suggest that PCT may support conventional morphological imaging in predicting meningioma grading before surgery. PMID:26246100

  3. Influence of vascular enhancement, age and gender on pulmonary perfused blood volume quantified by dual-energy-CTPA

    Energy Technology Data Exchange (ETDEWEB)

    Meinel, Felix G., E-mail: felix.meinel@med.uni-muenchen.de; Graef, Anita, E-mail: anita.graef@med.uni-muenchen.de; Sommer, Wieland H., E-mail: wieland.sommer@uni-muenchen.de; Thierfelder, Kolja M., E-mail: kolja.thierfelder@uni-muenchen.de; Reiser, Maximilian F., E-mail: maximilian.reiser@med.uni-muenchen.de; Johnson, Thorsten R.C., E-mail: thorsten.johnson@med.uni-muenchen.de

    2013-09-15

    Objectives: To determine the influence of technical and demographic parameters on quantification of pulmonary perfused blood volume (PBV) in dual energy computed tomography pulmonary angiography (DE-CTPA). Materials and methods: Pulmonary PBV was quantified in 142 patients who underwent DE-CTPA for suspected pulmonary embolism but in whom no thoracic pathologies were detected. Multivariate linear regression analysis was performed to calculate the influence of age, gender, enhancement of pulmonary trunk and enhancement difference between pulmonary trunk and left atrium (as a measure of timing) on PBV values. The resulting regression coefficients were used to calculate age-specific ranges of normal for PBV values adjusted for vascular enhancement and timing. Results: Enhancement of the pulmonary trunk (β = −0.29, p = 0.001) and enhancement difference between pulmonary trunk and left atrium (β = −0.24, p = 0.003) were found to significantly influence PBV values. Age (β = −0.33, p < 0.001) but not gender (β = 0.14, p = 0.05) had a significant negative influence on pulmonary PBV values. There was a 20% relative decrease of pulmonary PBV from patients aged <30 to patients over 80 years of age. Conclusions: DE-CTPA derived PBV values need to be corrected for age, vascular enhancement and timing but not for gender. The age-specific ranges of normal derived from this study can be used as a reference in future studies of PBV in pulmonary pathologies.

  4. Pre-operative grading of intracranial glioma. Comparison of MR-determined cerebral blood volume maps with thallium-201 SPECT

    International Nuclear Information System (INIS)

    Aim: To compare the accuracy of MR-determined cerebral blood volume (CBV) maps with SPECT imaging with thallium-201 in pre-operative grading of intracranial glioma. Material and Methods: Nineteen patients (7 female and 12 male, mean age 46.8 years) with intracranial gliomas were examined with MR perfusion imaging pre-operatively. Sixteen of these patients were also examined with SPECT imaging with thallium-201. The tumour to contralateral white matter NI (negative integral) and tracer uptake ratios were evaluated. The ratios in high-grade and low-grade tumours were compared. Results: The maximum CBV ratios of grades I and II gliomas (2.958±2.217) were significantly lower than the maximum CBV ratio of grades III and IV (9.484±4.520), p<0.001. There was no statistical difference when CBV ratios of grades I and II (p=0.381), grades II and III (p=0.229) and grades III and IV (p=0.476) gliomas were compared. Thallium SPECT imaging showed no difference in tumour uptake ratio between low-grade and high-grade gliomas (p=0.299). Conclusion: MR-determined NI was useful for pre-operative grading of intracranial gliomas but SPECT thallium-201 imaging was not

  5. Partial volume correction of the microPET blood input function using ensemble learning independent component analysis

    International Nuclear Information System (INIS)

    Medical images usually suffer from a partial volume effect (PVE), which may degrade the accuracy of any quantitative information extracted from the images. Our aim was to recreate accurate radioactivity concentration and time-activity curves (TACs) by microPET R4 quantification using ensemble learning independent component analysis (EL-ICA). We designed a digital cardiac phantom for this simulation and in order to evaluate the ability of EL-ICA to correct the PVE, the simulated images were convoluted using a Gaussian function (FWHM = 1-4 mm). The robustness of the proposed method towards noise was investigated by adding statistical noise (SNR = 2-16). During further evaluation, another set of cardiac phantoms were generated from the reconstructed images, and Poisson noise at different levels was added to the sinogram. In real experiments, four rat microPET images and a number of arterial blood samples were obtained; these were used to estimate the metabolic rate of FDG (MRFDG). Input functions estimated using the FastICA method were used for comparison. The results showed that EL-ICA could correct PVE in both the simulated and real cases. After correcting for the PVE, the errors for MRFDG, when estimated by the EL-ICA method, were smaller than those when TACs were directly derived from the PET images and when the FastICA approach was used.

  6. Influence of vascular enhancement, age and gender on pulmonary perfused blood volume quantified by dual-energy-CTPA

    International Nuclear Information System (INIS)

    Objectives: To determine the influence of technical and demographic parameters on quantification of pulmonary perfused blood volume (PBV) in dual energy computed tomography pulmonary angiography (DE-CTPA). Materials and methods: Pulmonary PBV was quantified in 142 patients who underwent DE-CTPA for suspected pulmonary embolism but in whom no thoracic pathologies were detected. Multivariate linear regression analysis was performed to calculate the influence of age, gender, enhancement of pulmonary trunk and enhancement difference between pulmonary trunk and left atrium (as a measure of timing) on PBV values. The resulting regression coefficients were used to calculate age-specific ranges of normal for PBV values adjusted for vascular enhancement and timing. Results: Enhancement of the pulmonary trunk (β = −0.29, p = 0.001) and enhancement difference between pulmonary trunk and left atrium (β = −0.24, p = 0.003) were found to significantly influence PBV values. Age (β = −0.33, p < 0.001) but not gender (β = 0.14, p = 0.05) had a significant negative influence on pulmonary PBV values. There was a 20% relative decrease of pulmonary PBV from patients aged <30 to patients over 80 years of age. Conclusions: DE-CTPA derived PBV values need to be corrected for age, vascular enhancement and timing but not for gender. The age-specific ranges of normal derived from this study can be used as a reference in future studies of PBV in pulmonary pathologies

  7. Non-invasive laser Doppler perfusion measurements of large tissue volumes and human skeletal muscle blood RMS velocity

    International Nuclear Information System (INIS)

    This study proposes the implementation of an algorithm allowing one to derive absolute blood root-mean-square (RMS) velocity values from laser Doppler perfusion meter (LDP) data. The algorithm is based on the quasi-elastic light scattering theory and holds for multiple scattering. While standard LDP measurements are normally applicable to a small region of interest (∼1 mm2), the present method allows the analysis of both small and large tissue volumes with small and large interoptode spacings (e.g., 1.5 cm). The applicability and the limits of the method are demonstrated with measurements on human skeletal muscle using a custom-built near-infrared LDP meter. Human brachioradialis muscle RMS velocity values of 9.99 ± 0.01 and 5.58 ± 0.03 mm s-1 at 1.5 cm and of 5.18 ± 0.01 and 2.54 ± 0.09 mm s-1 at 2 cm were found when the arm was (a) at rest and (b) occluded, respectively. At very large optode spacings or very high moving particle densities, the theory developed here would need to be amended to take into account second-order effects

  8. Evaluation of absolute left ventricular volume by gated equilibrium blood pool scintigraphy using count-based method. Clinical study

    Energy Technology Data Exchange (ETDEWEB)

    Anno, Hirofumi; Takeuchi, Akira; Ejiri, Kazutaka

    1987-12-01

    In order to estimate the absolute left ventricular volume (LVV) and the cradiac output (CO), gated equilibrium blood pool scintigraphy was performed. CO by radionuclide (RN) method was compared with CO simultaneously measured by thermodilution method (TDM) using Swan-Ganz catheter in 22 patients with cardiac diseases. To improve these determinations by RN, LVV using the count-based method was corrected by each of four transmission factors (TF1 = 1, TF2 (water) = e/sup -0.15d/, TF3 = e/sup -0.13d/ and TF4 = 1 - (1 - e/sup -0.125d/)/sup 1.26/ d: depth). We compared CO by RN with by TDM. CO by RN was significantly correlated with TDM: TF1 (CO (RN) = 0.23 x CO (TDM) + 0.08, r = 0.628, p < 0.002), TF (CO (RN) = 1.10 x CO (TDM) - 0.47, r = 0.914, p < 0.001), TF3 (CO (RN) = 0.89 x CO (TDM) - 0.30, r = 0.912, p < 0.001), and TF4 (CO (RN) = 0.71 x CO (TDM) - 0.23, r = 0.911, p < 0.001), respectively. These results indicate that the linear sttenuation correction is necessary and sufficient for accurate measurement of LVV and CO by RN using count-based method in clinical use.

  9. Thermal expansion

    International Nuclear Information System (INIS)

    Thermal expansion of fuel pellet is an important property which limits the lifetime of the fuels in reactors, because it affects both the pellet and cladding mechanical interaction and the gap conductivity. By fitting a number of available measured data, recommended equations have been presented and successfully used to estimate thermal expansion coefficient of the nuclear fuel pellet. However, due to large scatter of the measured data, non-consensus data have been omitted in formulating the equations. Also, the equation is strongly governed by the lack of appropriate experimental data. For those reasons, it is important to develop theoretical methodologies to better describe thermal expansion behaviour of nuclear fuel. In particular, first-principles and molecular dynamics simulations have been certainly contributed to predict reliable thermal expansion without fitting the measured data. Furthermore, the two theoretical techniques have improved on understanding the change of fuel dimension by describing the atomic-scale processes associated with lattice expansion in the fuels. (author)

  10. In Vitro Mean Red Blood Cell Volume Change Induced by Diode Pump Solid State Low-Level Laser of 405 nm

    Science.gov (United States)

    Jafar, Mohamad Suhaimi; Al-Gailani, Bassam T.; Ahmed, Naser Mahmoud; Suhaimi, Fatanah Mohamad; Suardi, Nursakinah

    2016-01-01

    Abstract Objective: This study was conducted to investigate the effects of low-level laser (LLL) doses on human red blood cell volume. The effects of exposure to a diode pump solid state (DPSS) (λ = 405 nm) laser were observed. Background data: The response of human blood to LLL irradiation gives important information about the mechanism of interaction of laser light with living organisms. Materials and methods Blood samples were collected into ethylenediaminetetraacetic acid (EDTA)-containing tubes, and each sample was divided into two equal aliquots, one to serve as control and the other for irradiation. The aliquot was subjected to laser irradiation for 20, 30, 40, or 50 min at a fixed power density of 0.03 W/cm2. Mean cell volume (MCV) and red blood cell (RBC) counts were measured immediately after irradiation using a computerized hemtoanalyzer. Results: Significant decrease in RBC volume (p < 0.05, p < 0.0001, p < 0.0001, and p < 0.05, respectively) was induced with variation in laser doses.The highest response was observed with an exposure time of 40 min. This result was reproduced in RBCs suspended in a buffered NaCl solution. In contrast to this finding, laser-induced RBC volume change was completely abolished by suspending RBCs in a solution containing a higher concentration of EDTA. Conclusions: It was suggested that LLL can reduce RBC volume possibly because of the increased free intracellular Ca+2 concentrations, which activate Ca+2-dependent K+ channels with consequent K+ ion efflux and cell shrinkage. PMID:26966989

  11. The influence of hyperoxia on regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV) and cerebral blood flow velocity in the middle cerebral artery (CBFVMCA) in human volunteers.

    Science.gov (United States)

    Kolbitsch, Christian; Lorenz, Ingo H; Hörmann, Christoph; Hinteregger, Martin; Löckinger, Alexander; Moser, Patrizia L; Kremser, Christian; Schocke, Michael; Felber, Stephan; Pfeiffer, Karl P; Benzer, Arnulf

    2002-09-01

    Conflicting results reported on the effects of hyperoxia on cerebral hemodynamics have been attributed mainly to methodical and species differences. In the present study contrast-enhanced magnetic resonance imaging (MRI) perfusion measurement was used to analyze the influence of hyperoxia (fraction of inspired oxygen (FiO2) = 1.0) on regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) in awake, normoventilating volunteers (n = 19). Furthermore, the experiment was repeated in 20 volunteers for transcranial Doppler sonography (TCD) measurement of cerebral blood flow velocity in the middle cerebral artery (CBFV(MCA)). When compared to normoxia (FiO2 = 0.21), hyperoxia heterogeneously influenced rCBV (4.95 +/- 0.02 to 12.87 +/- 0.08 mL/100g (FiO2 = 0.21) vs. 4.50 +/- 0.02 to 13.09 +/- 0.09 mL/100g (FiO2 = 1.0). In contrast, hyperoxia diminished rCBF in all regions (68.08 +/- 0.38 to 199.58 +/- 1.58 mL/100g/min (FiO2 = 0.21) vs. 58.63 +/- 0.32 to 175.16 +/- 1.51 mL/100g/min (FiO2 = 1.0)) except in parietal and left frontal gray matter. CBFV(MCA) remained unchanged regardless of the inspired oxygen fraction (62 +/- 9 cm/s (FiO2 = 0.21) vs. 64 +/- 8 cm/s (FiO2 = 1.0)). Finding CBFV(MCA) unchanged during hyperoxia is consistent with the present study's unchanged rCBF in parietal and left frontal gray matter. In these fronto-parietal regions predominantly fed by the middle cerebral artery, the vasoconstrictor effect of oxygen was probably counteracted by increased perfusion of foci of neuronal activity controlling general behavior and arousal. PMID:12413599

  12. Correlation between stroke volume variation and blood volume during hypovolemia%低血容量状态下患者每搏量变异度与血容量的相关性

    Institute of Scientific and Technical Information of China (English)

    李文静; 李健; 彭科; 姜亚辉; 张慧娟; 嵇富海

    2012-01-01

    目的 探讨低血容量状态下患者每搏量变异度(SVV)与血容量的相关性.方法 择期骨科手术患者20例,年龄20 ~ 64岁,BMI 20 ~ 30 kg/m2,ASA分级Ⅰ或Ⅱ级.气管插管后,稳定5 min,记录HR、MAP、CVP、动脉压力波形监测的心排量(APCO)、SVV、全身血管阻力(SVR)和心脏指数(CI).以30 ~ 50 ml/min的速率从中心静脉取血,取血量为全身血容量的5%,待血液动力学稳定5 min后记录上述血液动力学指标;再次以上述方法采血并记录血液动力学指标;随后以50 ~ 70 ml/min的速率经右侧颈内静脉输注相当于全身血容量5%的6%羟乙基淀粉130/0.4,待血液动力学稳定5 min后记录血液动力学指标;再次以上述方法补液并记录血液动力学指标.血容量变化(各时点血容量与基础值的差值)与dSVV(各时点监测值与基础值的差值)行线性相关分析.结果 每次血容量变化后SVV、APCO和CI与前一状态比较差异均有统计学意义(P<0.05或0.01),每次血容量变化后HR、MAP、CVP和SVR与前一状态比较差异并非均有统计学意义;dSVV与血容量变化呈负相关(r=-0.875,P<0.01).结论 低容量状态下SVV与血容量的相关性较高,可准确反映血容量的变化,可用于指导低血量容状态下的容量治疗.%Objective To investigate the correlation between stroke volume variation (SVV) and blood volume during hypovolemia.Methods Twenty ASA Ⅰ or Ⅱ patients,aged 20-64 yr,with body mass index 20-30 kg/m2,scheduled for elective orthopedic operation,were studied.Anesthesia was induced with dexamethasone,midazolam,propofol,fentanyl and cisatracurium and maintained with sevoflurane,fentanyl and cisatracurium.The patients were tracheal intubated and mechanically ventilated.HR,MAP,CVP,arterial pressure-based cardiac output (APCO),SVV,systemic vascular resistance (SVR) and cardiac index (CI) were recorded 5 min after tracheal intubation.Blood was taken from central vein at a

  13. Quantification of serial changes in cerebral blood volume and metabolism in patients with recurrent glioblastoma undergoing antiangiogenic therapy

    International Nuclear Information System (INIS)

    Highlights: • Antiangiogenic therapy can lead to a decreased in CBV in normal brain tissue. • Responding and pseudoresponding lesions to AAT showed a similar CBV decrease. • Cho and NAA allowed for a distinction of responding and pseudoresponding lesions. • Cr ratios are not suited for evaluation of antiangiogenic therapy response. • Responders to AAT may have an increased risk for remote progression of the GBM. - Abstract: Objectives: To evaluate the usefulness of quantitative advanced magnetic resonance imaging (MRI) methods for assessment of antiangiogenic therapy (AAT) response in recurrent glioblastoma multiforme (GBM). Methods: Eighteen patients with recurrent GBM received bevacizumab and 18 patients served as control group. Baseline MRI and two follow-up examinations were acquired every 3–5 months using dynamic susceptibility-weighted contrast (DSC) perfusion MRI and 1H-MR spectroscopic imaging (1H-MRSI). Maps of absolute cerebral blood volume (aCBV) were coregistered with choline (Cho) and N-acetyl-aspartate (NAA) concentrations and compared to usually used relative parameters as well as controls. Results: Perfusion significantly decreased in responding and pseudoresponding GBMs but also in normal appearing brain after AAT onset. Cho and NAA concentrations were superior to Cr-ratios in lesion differentiation and showed a clear gap between responding and pseudoresponding lesions. Responders to AAT exceptionally frequently (6 out of 8 patients) showed remote GBM progression. Conclusions: Quantification of CBV reveals changes in normal brain perfusion due to AAT, which were not described so far. DSC perfusion MRI seems not to be suitable for differentiation between response and pseudoresponse to AAT. However, absolute quantification of brain metabolites may allow for distinction due to a clear gap at 6–9 months after therapy onset

  14. Do Sustained Lung Inflations during Neonatal Resuscitation Affect Cerebral Blood Volume in Preterm Infants? A Randomized Controlled Pilot Study.

    Directory of Open Access Journals (Sweden)

    Bernhard Schwaberger

    Full Text Available Sustained lung inflations (SLI during neonatal resuscitation may promote alveolar recruitment in preterm infants. While most of the studies focus on respiratory outcome, the impact of SLI on the brain hasn't been investigated yet.Do SLI affect cerebral blood volume (CBV in preterm infants?Preterm infants of gestation 28 weeks 0 days to 33 weeks 6 days with requirement for respiratory support (RS were included in this randomized controlled pilot trial. Within the first 15 minutes after birth near-infrared spectroscopy (NIRS measurements using 'NIRO-200-NX' (Hamamatsu, Japan were performed to evaluate changes in CBV and cerebral tissue oxygenation. Two groups were compared based on RS: In SLI group RS was given by applying 1-3 SLI (30 cmH2O for 15 s continued by respiratory standard care. Control group received respiratory standard care only.40 infants (20 in each group with mean gestational age of 32 weeks one day (±2 days and birth weight of 1707 (±470 g were included. In the control group ΔCBV was significantly decreasing, whereas in SLI group ΔCBV showed similar values during the whole period of 15 minutes. Comparing both groups within the first 15 minutes ΔCBV showed a tendency toward different overall courses (p = 0.051.This is the first study demonstrating an impact of SLI on CBV. Further studies are warranted including reconfirmation of the present findings in infants with lower gestational age. Future investigations on SLI should not only focus on respiratory outcome but also on the consequences on the developing brain.German Clinical Trials Register DRKS00005161 https://drks-neu.uniklinik-freiburg.de/drks_web/setLocale_EN.do.

  15. Added value of lung perfused blood volume images using dual-energy CT for assessment of acute pulmonary embolism

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Kunihiro, Yoshie [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Kudomi, Shohei; Yonezawa, Teppei [Department of Radiology, Yamaguchi University Hospital, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St. Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

    2015-01-15

    Purpose: To investigate the added value of lung perfused blood volume (LPBV) using dual-energy CT for the evaluation of intrapulmonary clot (IPC) in patients suspected of having acute pulmonary embolism (PE). Materials and methods: Institutional review board approval was obtained for this retrospective study. Eighty-three patients suspected of having PE who underwent CT pulmonary angiography (CTPA) using a dual-energy technique were enrolled in this study. Two radiologists who were blinded retrospectively and independently reviewed CTPA images alone and the combined images with color-coded LPBV over a 4-week interval, and two separate sessions were performed with a one-month interval. Inter- and intraobserver variability and diagnostic accuracy were evaluated for each reviewer with receiver operating characteristic (ROC) curve analysis. Results: Values for inter- and intraobserver agreement, respectively, were better for CTPA combined with LPBV (ICC = 0.847 and 0.937) than CTPA alone (ICC = 0.748 and 0.861). For both readers, diagnostic accuracy (area under the ROC curve [A{sub z}]) were also superior, when CTPA alone (A{sub z} = 0.888 [reader 1] and 0.912 [reader 2]) was compared with that after the combination with LPBV images (A{sub z} = 0.966 [reader 1] and 0.959 [reader 2]) (p < 0.001). However, A{sub z} values of both images might not have significant difference in statistics, because A{sub z} value of CTPA alone was high and 95% confidence intervals overlapped in both images. Conclusion: Addition of dual-energy perfusion CT to CTPA improves detection of peripheral IPCs with better interobserver agreement.

  16. Quantification of serial changes in cerebral blood volume and metabolism in patients with recurrent glioblastoma undergoing antiangiogenic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Stadlbauer, Andreas, E-mail: andi@nmr.at [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria); Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen (Germany); Department of Radiology and Nuclear Medicine, Medical University Vienna, Währinger Gürtel 18-20, A-1097 Vienna (Austria); Pichler, Petra [First Department of Internal Medicine, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Poelten (Austria); Karl, Marianne [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria); Brandner, Sebastian [Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen (Germany); Lerch, Claudia [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria); Renner, Bertold [Institute of Experimental and Clinical Pharmacology and Toxicology, University of Erlangen-Nürnberg, Erlangen (Germany); Heinz, Gertraud [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria)

    2015-06-15

    Highlights: • Antiangiogenic therapy can lead to a decreased in CBV in normal brain tissue. • Responding and pseudoresponding lesions to AAT showed a similar CBV decrease. • Cho and NAA allowed for a distinction of responding and pseudoresponding lesions. • Cr ratios are not suited for evaluation of antiangiogenic therapy response. • Responders to AAT may have an increased risk for remote progression of the GBM. - Abstract: Objectives: To evaluate the usefulness of quantitative advanced magnetic resonance imaging (MRI) methods for assessment of antiangiogenic therapy (AAT) response in recurrent glioblastoma multiforme (GBM). Methods: Eighteen patients with recurrent GBM received bevacizumab and 18 patients served as control group. Baseline MRI and two follow-up examinations were acquired every 3–5 months using dynamic susceptibility-weighted contrast (DSC) perfusion MRI and {sup 1}H-MR spectroscopic imaging ({sup 1}H-MRSI). Maps of absolute cerebral blood volume (aCBV) were coregistered with choline (Cho) and N-acetyl-aspartate (NAA) concentrations and compared to usually used relative parameters as well as controls. Results: Perfusion significantly decreased in responding and pseudoresponding GBMs but also in normal appearing brain after AAT onset. Cho and NAA concentrations were superior to Cr-ratios in lesion differentiation and showed a clear gap between responding and pseudoresponding lesions. Responders to AAT exceptionally frequently (6 out of 8 patients) showed remote GBM progression. Conclusions: Quantification of CBV reveals changes in normal brain perfusion due to AAT, which were not described so far. DSC perfusion MRI seems not to be suitable for differentiation between response and pseudoresponse to AAT. However, absolute quantification of brain metabolites may allow for distinction due to a clear gap at 6–9 months after therapy onset.

  17. The value of maximal blood flow volume on duplex ultrasonography for the diagnosis of arteriogenic erectile dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Ku, Ja Hyeon [Soonchunhyang University School of Medicine, Chunan (Korea, Republic of); Song, Yun Seob; Kim, Min Eui; Park, Young Ho; Lee, Hye Kyoung [Seoul and Military Manpower Administration, Taejeon (Korea, Republic of)

    2001-03-15

    To evaluate the usefulness of maximal blood flow volume (MBFV) measured by duplex ultrasonography (US) compared with penile tumescence measured by RigiScan in the diagnosis of arteriogenic erectile dysfunction (ED). This study included twenty six patients who performed both RigiScan and duplex US after intracorporeal injection of Prostaglandin EL. We measured tumescences of penile tip and base using RigiScan and maximal arterial diameter (MAD) and peak systolic velocity (PSV) using a 7 MHz color Doppler unit. MBFV was defined as (MAD/2){sup 2} X pi X PSV. Based on normal value, we compared MAD and MBFV, and PSV and MBFV and the correlations of each measurements were evaluated with Spearman's correlation analysis. The level of significance was P<0.05. The results between MAD and MBFV, and PSV ad MBFV based on normal values were similar, respectively. Tumescences of penile tip and base were significantly correlated with MAD (r=0.409, r=0.52, p<0.05), and PSV (r=0.565, r=0.396, p<0.05). MBFV was also significantly correlated with tumescences od penile tip and base (r=0.502, r=0.563, p<0.05). In 4 patients with abnormal MAD and normal PSV, 3 had abnormal MBFV and 1 had normal MBFV. All 3 patients with abnormal MBFV had abnormal penile tumescence and 1 patients with normal MBFV had normal tumescence. One patients with normal MAD and abnormal PSV had abnormal MBFV and penile tumescence. In our study, MBFV was accurate in the diagnosis of arteriogenic ED. Moreover, MBFV was usefulness in the diagnosis of arteriogenic ED as it could explain the case where MAD and PSV are not accoded.

  18. The value of maximal blood flow volume on duplex ultrasonography for the diagnosis of arteriogenic erectile dysfunction

    International Nuclear Information System (INIS)

    To evaluate the usefulness of maximal blood flow volume (MBFV) measured by duplex ultrasonography (US) compared with penile tumescence measured by RigiScan in the diagnosis of arteriogenic erectile dysfunction (ED). This study included twenty six patients who performed both RigiScan and duplex US after intracorporeal injection of Prostaglandin EL. We measured tumescences of penile tip and base using RigiScan and maximal arterial diameter (MAD) and peak systolic velocity (PSV) using a 7 MHz color Doppler unit. MBFV was defined as (MAD/2)2 X π X PSV. Based on normal value, we compared MAD and MBFV, and PSV and MBFV and the correlations of each measurements were evaluated with Spearman's correlation analysis. The level of significance was P<0.05. The results between MAD and MBFV, and PSV ad MBFV based on normal values were similar, respectively. Tumescences of penile tip and base were significantly correlated with MAD (r=0.409, r=0.52, p<0.05), and PSV (r=0.565, r=0.396, p<0.05). MBFV was also significantly correlated with tumescences od penile tip and base (r=0.502, r=0.563, p<0.05). In 4 patients with abnormal MAD and normal PSV, 3 had abnormal MBFV and 1 had normal MBFV. All 3 patients with abnormal MBFV had abnormal penile tumescence and 1 patients with normal MBFV had normal tumescence. One patients with normal MAD and abnormal PSV had abnormal MBFV and penile tumescence. In our study, MBFV was accurate in the diagnosis of arteriogenic ED. Moreover, MBFV was usefulness in the diagnosis of arteriogenic ED as it could explain the case where MAD and PSV are not accoded.

  19. Relative cerebral blood volume measurements of low-grade gliomas predict patient outcome in a multi-institution setting

    International Nuclear Information System (INIS)

    Background/purpose: The prognostic value of defining subcategories of gliomas is still controversial. This study aims to determine the utility of relative cerebral blood volume (rCBV) in predicting clinical response in patients with low-grade glioma at multiple institutions. Materials and methods: Sixty-nine patients were studied with dynamic susceptibility contrast-enhanced perfusion MRI at two institutions. The pathologic diagnoses of the low-grade gliomas were 34 astrocytomas, 20 oligodendroglioma, 9 oligoastrocytomas, 1 ganglioglioma and 5 with indeterminate histology. Wilcoxon tests were used to compare patients in different response categories with respect to baseline rCBV. Kaplan-Meier curve and log-rank tests were used to predict the association of rCBV with time to progression. Results: At both institutions, patients with an adverse event (progressive disease or death) had a significantly higher baseline rCBV than those without (complete response or stable disease) (p value = 0.0138). The odds ratio for detecting an adverse event when using rCBV was 1.87 (95% confidence interval: 1.14-3.08). rCBV was significantly negatively associated with time to progression (p = 0.005). The median time to progression among subjects with rCBV > 1.75 was 365 days, while there was 95% confidence that the median time to progression was at least 889 days among subjects with rCBV < 1.75. Conclusion: Our study suggests not only that rCBV measurements correlate well with time to progression or death, but also that the findings can be replicated across institutions, which supports the application of rCBV as an adjunct to pathology in predicting glioma biology.

  20. Cryopreservation of blood mononuclear leukocytes and stem cells suspended in a large fluid volume. A preclinical model for a blood stem cell bank.

    Science.gov (United States)

    Fliedner, T M; Körbling, M; Calvo, W; Bruch, C; Herbst, E

    1977-09-29

    It was the purpose of this study to establish and evaluate a freezing-and-thawing method for preservation of hemopoietic stem cells from the peripheral blood. Blood leukocytes collected by means of an IBM Blood-Cell-Separator were frozen in plastic bags using 10% DMSO and controlled cooling rates. Thawing was performed rapidly, and DMSO was diluted and removed prior to the in-vitro and in-vivo assays. The mean recovery of mononuclear cells collected from 82 leukaphereses was 86%. To assess the recovery of cryopreserved hemopoietic stem cells, the soft agar culture method adapted for the dog was used. There was no significant difference in the CFUc recovery per 1 X 10(6) mononuclear cells or in per leukapheresis after different cryopreservation times (1--6 and 7--27 months). To evaluate the hemopoietic repopulation capability of cryopreserved blood stem cells, leukapheresis-derived leukocytes were transfused into 1200 R whole body x-irradiated dogs. The hemopoietic repopulation pattern at day 10 after transfusion of comparable numbers of fresh or frozen leukocytes was not significantly different, as measured in bone marrow smears and sections and by granulocyte concentration in the peripheral blood. PMID:912104

  1. A new method to study changes in microvascular blood volume in muscle and adipose tissue: Real time imaging in humans and rat

    DEFF Research Database (Denmark)

    Sjøberg, Kim Anker; Rattigan, Stephen; Hiscock, Natalie J;

    2011-01-01

    We employed and evaluated a new application of contrast enhanced ultrasound for real time imaging of changes in microvascular blood volume (MVB) in tissues in females, males and rat. Continuous real time imaging was performed using contrast enhanced ultrasound to quantify infused gas filled micro...... real time imaging the method has wide applications for determining MBV in different organs during various physiological or pathophysiological conditions....

  2. Bidirectional Contrast agent leakage correction of dynamic susceptibility contrast (DSC)-MRI improves cerebral blood volume estimation and survival prediction in recurrent glioblastoma treated with bevacizumab.

    OpenAIRE

    Ab, KL; Boxerman, JL; Lai, A.; Nghiemphu, PL; Pope, WB; Cloughesy, TF; Ellingson, BM

    2016-01-01

    To evaluate a leakage correction algorithm for T1 and T2* artifacts arising from contrast agent extravasation in dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) that accounts for bidirectional contrast agent flux and compare relative cerebral blood volume (CBV) estimates and overall survival (OS) stratification from this model to those made with the unidirectional and uncorrected models in patients with recurrent glioblastoma (GBM).We determined median rCBV within contras...

  3. Carbogen Breathing Differentially Enhances Blood Plasma Volume and 5-Fluorouracil Uptake in Two Murine Colon Tumor Models with a Distinct Vascular Structure

    Directory of Open Access Journals (Sweden)

    Hanneke W.M. van Laarhoven

    2006-06-01

    Full Text Available For the systemic treatment of colorectal cancer, 5-fluorouracil (FU-based chemotherapy is the standard. However, only a subset of patients responds to chemotherapy. Breathing of carbogen (95% O2 and 5% CO2 may increase the uptake of FU through changes in tumor physiology. This study aims to monitor in animal models in vivo the effects of carbogen breathing on tumor blood plasma volume, pH, and energy status, and on FU uptake and metabolism in two colon tumor models C38 and C26a, which differ in their vascular structure and hypoxic status. Phosphorus-31 magnetic resonance spectroscopy (MRS was used to assess tumor pH and energy status, and fluorine-19 MRS was used to follow FU uptake and metabolism. Advanced magnetic resonance imaging methods using ultrasmall particles of iron oxide were performed to assess blood plasma volume. The results showed that carbogen breathing significantly decreased extracellular pH and increased tumor blood plasma volume and FU uptake in tumors. These effects were most significant in the C38 tumor line, which has the largest relative vascular area. In the C26a tumor line, carbogen breathing increased tumor growth delay by FU. In this study, carbogen breathing also enhanced systemic toxicity by FU.

  4. Thermal expansion, isothermal compression and heat capacity difference at constant pressure and constant volume in solid solutions (TiGaSe3)1-x(TiInS3)x (x=0.1; 0.2)

    International Nuclear Information System (INIS)

    The temperature dependences of thermal expansion and isothermal compression of (TiGaSe3)0.9(TiInS3)0.1 and (TiGaSe2)0.8(TiInS2)0.2 are investigated. The heat capacity difference at constant pressure and volume is calculated on the base of experimental data. It is established that interactions which are connected with the increase of defect number and weakening of chemical bond in lattice, increases with temperature increase and increase of tiInS2 content in composition

  5. Cerebral blood volume calculated by dynamic susceptibility contrast-enhanced perfusion MR imaging: preliminary correlation study with glioblastoma genetic profiles.

    Directory of Open Access Journals (Sweden)

    Inseon Ryoo

    Full Text Available PURPOSE: To evaluate the usefulness of dynamic susceptibility contrast (DSC enhanced perfusion MR imaging in predicting major genetic alterations in glioblastomas. MATERIALS AND METHODS: Twenty-five patients (M:F = 13∶12, mean age: 52.1±15.2 years with pathologically proven glioblastoma who underwent DSC MR imaging before surgery were included. On DSC MR imaging, the normalized relative tumor blood volume (nTBV of the enhancing solid portion of each tumor was calculated by using dedicated software (Nordic TumorEX, NordicNeuroLab, Bergen, Norway that enabled semi-automatic segmentation for each tumor. Five major glioblastoma genetic alterations (epidermal growth factor receptor (EGFR, phosphatase and tensin homologue (PTEN, Ki-67, O6-methylguanine-DNA methyltransferase (MGMT and p53 were confirmed by immunohistochemistry and analyzed for correlation with the nTBV of each tumor. Statistical analysis was performed using the unpaired Student t test, ROC (receiver operating characteristic curve analysis and Pearson correlation analysis. RESULTS: The nTBVs of the MGMT methylation-negative group (mean 9.5±7.5 were significantly higher than those of the MGMT methylation-positive group (mean 5.4±1.8 (p = .046. In the analysis of EGFR expression-positive group, the nTBVs of the subgroup with loss of PTEN gene expression (mean: 10.3±8.1 were also significantly higher than those of the subgroup without loss of PTEN gene expression (mean: 5.6±2.3 (p = .046. Ki-67 labeling index indicated significant positive correlation with the nTBV of the tumor (p = .01. CONCLUSION: We found that glioblastomas with aggressive genetic alterations tended to have a high nTBV in the present study. Thus, we believe that DSC-enhanced perfusion MR imaging could be helpful in predicting genetic alterations that are crucial in predicting the prognosis of and selecting tailored treatment for glioblastoma patients.

  6. [Interpretation and use of routine pulmonary function tests: Spirometry, static lung volumes, lung diffusion, arterial blood gas, methacholine challenge test and 6-minute walk test].

    Science.gov (United States)

    Bokov, P; Delclaux, C

    2016-02-01

    Resting pulmonary function tests (PFT) include the assessment of ventilatory capacity: spirometry (forced expiratory flows and mobilisable volumes) and static volume assessment, notably using body plethysmography. Spirometry allows the potential definition of obstructive defect, while static volume assessment allows the potential definition of restrictive defect (decrease in total lung capacity) and thoracic hyperinflation (increase in static volumes). It must be kept in mind that this evaluation is incomplete and that an assessment of ventilatory demand is often warranted, especially when facing dyspnoea: evaluation of arterial blood gas (searching for respiratory insufficiency) and measurement of the transfer coefficient of the lung, allowing with the measurement of alveolar volume to calculate the diffusing capacity of the lung for CO (DLCO: assessment of alveolar-capillary wall and capillary blood volume). All these pulmonary function tests have been the subject of an Americano-European Task force (standardisation of lung function testing) published in 2005, and translated in French in 2007. Interpretative strategies for lung function tests have been recommended, which define abnormal lung function tests using the 5th and 95th percentiles of predicted values (lower and upper limits of normal values). Thus, these recommendations need to be implemented in all pulmonary function test units. A methacholine challenge test will only be performed in the presence of an intermediate pre-test probability for asthma (diagnostic uncertainty), which is an infrequent setting. The most convenient exertional test is the 6-minute walk test that allows the assessment of walking performance, the search for arterial desaturation and the quantification of dyspnoea complaint. PMID:26657268

  7. Susceptibility Contrast Magnetic Resonance Imaging Determination of Fractional Tumor Blood Volume: A Noninvasive Imaging Biomarker of Response to the Vascular Disrupting Agent ZD6126

    International Nuclear Information System (INIS)

    Purpose: To assess tumor fractional blood volume (ξ), determined in vivo by susceptibility contrast magnetic resonance imaging (MRI) as a noninvasive imaging biomarker of tumor response to the vascular disrupting agent ZD6126. Methods and Materials: The transverse MRI relaxation rate R2* of rat GH3 prolactinomas was quantified prior to and following injection of 2.5 mgFe/kg feruglose, an ultrasmall superparamagnetic iron oxide intravascular contrast agent, and ξ (%) was determined from the change in R2*. The rats were then treated with either saline or 50 mg/kg ZD6126, and ξ measured again 24 hours later. Following posttreatment MRI, Hoechst 33342 (15 mg/kg) was administered to the rats and histological correlates from composite images of tumor perfusion and necrosis sought. Results: Irrespective of treatment, tumor volume significantly increased over 24 hours. Saline-treated tumors showed no statistically significant change in ξ, whereas a significant (p = 0.002) 70% reduction in ξ of the ZD6126-treated cohort was determined. Hoechst 33342 uptake was associated with viable tumor tissue and was significantly (p = 0.004) reduced and restricted to the rim of the ZD6126-treated tumors. A significant positive correlation between posttreatment ξ and Hoechst 33342 uptake was obtained (r = 0.83, p = 0.002), providing validation of the MRI-derived measurements of fractional tumor blood volume. Conclusions: These data clearly highlight the potential of susceptibility contrast MRI with ultrasmall superparamagnetic iron oxide contrast agents to provide quantitative imaging biomarkers of fractional tumor blood volume at high spatial resolution to assess tumor vascular status and response to vascular disrupting agents

  8. Study of the multifragmentation in central collisions of the system: 129Xe + natSn between 32 and 50 MeV/A: measurement of collective expansion energy and of freeze-out volume

    International Nuclear Information System (INIS)

    The multifragmentation of the nuclear system formed in the central collisions of the Xe+Sn reaction between 32 and 50 MeV/A has been studied with the INDRA detector. A tensorial analyse is used to select central collisions. An important part of the charge (about 85 %) is isotropically emitted. The charge partitions have the characteristics of a simultaneous multiple fragment emission. The shape of the fragment kinetic energy distributions together with the reduced velocity correlation functions indicate that the fragmentation is a simultaneous process that occurs at low density. A comparison between the experimental data and predictions of the statistical multifragmentation model of Copenhagen (SMM) shows that charge partitions agree with the hypothesis of a thermodynamical equilibrium, whereas, kinetic observables are more constraining to the model and difficult to reproduce. However, fragments correlation functions are used in order to extract the freeze-out volume and the collective radial energy. At 50 MeV/A, the freeze-out volume is estimated to be 2.7 times the normal volume. It decreases with incident energy to be nearly twice the normal volume at 32 MeV/S. The collective energy evolves from 0 to 1.3 MeV/A with the bombarding energy. This expansion is not purely thermal and originates probably from a dynamical compression developed in the early stage of the collision. (author)

  9. Wien Automatic System Planning (WASP) Package. A computer code for power generating system expansion planning. Version WASP-III Plus. User's manual. Volume 1: Chapters 1-11

    International Nuclear Information System (INIS)

    As a continuation of its effort to provide comprehensive and impartial guidance to Member States facing the need for introducing nuclear power, the IAEA has completed a new version of the Wien Automatic System Planning (WASP) Package for carrying out power generation expansion planning studies. WASP was originally developed in 1972 in the USA to meet the IAEA's needs to analyze the economic competitiveness of nuclear power in comparison to other generation expansion alternatives for supplying the future electricity requirements of a country or region. The model was first used by the IAEA to conduct global studies (Market Survey for Nuclear Power Plants in Developing Countries, 1972-1973) and to carry out Nuclear Power Planning Studies for several Member States. The WASP system developed into a very comprehensive planning tool for electric power system expansion analysis. Following these developments, the so-called WASP-Ill version was produced in 1979. This version introduced important improvements to the system, namely in the treatment of hydroelectric power plants. The WASP-III version has been continually updated and maintained in order to incorporate needed enhancements. In 1981, the Model for Analysis of Energy Demand (MAED) was developed in order to allow the determination of electricity demand, consistent with the overall requirements for final energy, and thus, to provide a more adequate forecast of electricity needs to be considered in the WASP study. MAED and WASP have been used by the Agency for the conduct of Energy and Nuclear Power Planning Studies for interested Member States. More recently, the VALORAGUA model was completed in 1992 as a means for helping in the preparation of the hydro plant characteristics to be input in the WASP study and to verify that the WASP overall optimized expansion plan takes also into account an optimization of the use of water for electricity generation. The combined application of VALORAGUA and WASP permits the

  10. Isolation of mesenchymal stromal/stem cells from small-volume umbilical cord blood units that do not qualify for the banking system.

    Science.gov (United States)

    Yoshioka, Satoshi; Miura, Yasuo; Iwasa, Masaki; Fujishiro, Aya; Yao, Hisayuki; Miura, Masako; Fukuoka, Masaaki; Nakagawa, Yoko; Yokota, Asumi; Hirai, Hideyo; Ichinohe, Tatsuo; Takaori-Kondo, Akifumi; Maekawa, Taira

    2015-08-01

    The clinical application of mesenchymal stromal/stem cells (MSCs) has been extensively explored. In this study, we examined the availability of freshly donated umbilical cord blood (UCB) units that do not qualify for the Japanese banking system for transplantation because of their small volume as a source of MSCs. Forty-five UCB units were used. The median volume of each UCB unit and number of nucleated cells per unit were 40 mL and 5.39 × 10(8), respectively. MSCs were successfully isolated from 18 of 45 units (40 %). The MSC isolation rate was not affected by cell processing method or the interval between delivery and cell processing. The volume of the UCB unit and the mononuclear cell count were predictive factors of the MSC isolation rate. MSCs were effectively isolated by selecting UCB units with a volume of ≥54 mL and containing ≥1.28 × 10(8) mononuclear cells, yielding a MSC isolation rate of >70 %. UCB-derived MSCs were similar to bone marrow-derived MSCs in terms of their morphology, surface marker expression, and differentiation potential, apart from adipogenesis. Our data indicate that UCB units that are currently discarded due to inadequate volume should be reconsidered as a source of MSCs using the well-established UCB banking system. PMID:26121953

  11. Expansion of Natural Killer Cells in Peripheral Blood in a Japanese Elderly with Human T-Cell Lymphotropic Virus Type 1-Related Skin Lesions

    Directory of Open Access Journals (Sweden)

    Shinsaku Imashuku

    2014-01-01

    Full Text Available Natural killer (NK cells were proposed to play an important role in the pathogenesis of human T-cell lymphotropic virus type 1- (HTLV-1- associated neurologic disease. Our patient was a 77-year-old Japanese man, who had been treated for infective dermatitis associated with HTLV-1 for nearly 10 years. When referred to us, he had facial eczema/edema as well as extensive dermatitis at the neck/upper chest and nuchal area/upper back regions. Dermal lesions had CD3+CD4+ cells, but no NK cells. Flow cytometry of his peripheral blood showed a phenotype of CD2+ (97%, CD3+ (17%, CD4+ (12%, CD7+ (94%, CD8+ (6%, CD11c+ (70%, CD16+ (82%, CD19+ (0%, CD20+ (0%, CD56+ (67%, HLA-DR+ (68%, and NKp46+ (36%. Absolute numbers of CD56+NK cells in the peripheral blood were in a range of 986/μL–1,270/μL. The expanded NK cells in the peripheral blood are considered to be reactive, to maintain the confinement of the HTLV-1-positive CD4+ cells in the skin, and to prevent the progression of the disease.

  12. Iodine status and its correlations with age, blood pressure, and thyroid volume in South Indian women above 35 years of age (Amrita Thyroid Survey

    Directory of Open Access Journals (Sweden)

    Vadayath Usha Menon

    2011-01-01

    Full Text Available Background: Thyroid disorders are more commonly seen among females and the prevalence increases with age. There is no population data from India focusing on iodine levels and their correlations with thyroid volume and other factors in adult women. Aim: This study was designed to establish the iodine status and its relation with various factors including thyroid volume measured by ultrasound among the females of Kerala. Materials and Methods: This was a cross sectional house to house survey among the females above 35 years of age in a randomly selected urban area in Cochin Corporation, Kerala State, India. Selected subjects were interviewed, examined and blood and urine tests were done. Thyroid volume was calculated using ultrasound. Results: Among the 508 subjects who participated in the checkup, 471 subjects were included for analysis. Mean age was 50.3 + 10.7 years and 53.2% were postmenopausal. A total of 98% of the subjects were using iodized salt and median urinary iodine excretion (UIE was 162.6 mcg/l. UIE had negative correlation with age and systolic blood pressure (BP, but had no correlation with thyroid volume (TV, thyroid nodularity, free thyroxine 4 (FT4, thyroid stimulating hormone (TSH or anti thyroid peroxidase (TPO levels. Iodine deficiency was more commonly seen in subjects with hypertension and also among postmenopausal females. Conclusions: This study showed that females > 35 years were iodine sufficient, though one third of the subjects had UIE levels less than the recommended level. Iodine levels had significant negative correlation with age and systolic BP and no correlation with thyroid volume or biochemical parameters. Iodine deficiency was significantly higher in subjects with new and known hypertension and this relation merits further evaluation.

  13. Pulse pressure variation and volume responsiveness during acutely increased pulmonary artery pressure: an experimental study

    OpenAIRE

    Daudel, Fritz; Tüller, David; Krähenbühl, Stefanie; Jakob, Stephan M; Takala, Jukka

    2010-01-01

    Introduction We found that pulse pressure variation (PPV) did not predict volume responsiveness in patients with increased pulmonary artery pressure. This study tests the hypothesis that PPV does not predict fluid responsiveness during an endotoxin-induced acute increase in pulmonary artery pressure and right ventricular loading. Methods Pigs were subjected to endotoxemia (0.4 μg/kg/hour lipopolysaccharide), followed by volume expansion, subsequent hemorrhage (20% of estimated blood volume), ...

  14. Study of the multifragmentation in central collisions of the system: {sup 129}Xe + {sup nat}Sn between 32 and 50 MeV/A: measurement of collective expansion energy and of freeze-out volume; Etude de la multifragmentation dans les collisions centrales pour le systeme {sup 129}Xe + {sup nat}Sn entre 32 et 50 MeV/A: mesure de l`energie collective d`expansion et du volume de freeze-out

    Energy Technology Data Exchange (ETDEWEB)

    Salou, S

    1997-12-05

    The multifragmentation of the nuclear system formed in the central collisions of the Xe+Sn reaction between 32 and 50 MeV/A has been studied with the INDRA detector. A tensorial analyse is used to select central collisions. An important part of the charge (about 85 %) is isotropically emitted. The charge partitions have the characteristics of a simultaneous multiple fragment emission. The shape of the fragment kinetic energy distributions together with the reduced velocity correlation functions indicate that the fragmentation is a simultaneous process that occurs at low density. A comparison between the experimental data and predictions of the statistical multifragmentation model of Copenhagen (SMM) shows that charge partitions agree with the hypothesis of a thermodynamical equilibrium, whereas, kinetic observables are more constraining to the model and difficult to reproduce. However, fragments correlation functions are used in order to extract the freeze-out volume and the collective radial energy. At 50 MeV/A, the freeze-out volume is estimated to be 2.7 times the normal volume. It decreases with incident energy to be nearly twice the normal volume at 32 MeV/S. The collective energy evolves from 0 to 1.3 MeV/A with the bombarding energy. This expansion is not purely thermal and originates probably from a dynamical compression developed in the early stage of the collision. (author) 88 refs.

  15. Dynamic contrast-enhanced x-ray CT measurement of cerebral blood volume in a rabbit tumor model

    Science.gov (United States)

    Cenic, Aleksa; Lee, Ting-Yim; Craen, Rosemary A.; Gelb, Adrian W.

    1998-07-01

    Cerebral blood volume (CBV) is a major determinant of intracranial pressure (ICP). Hyperventilation is commonly employed to reduce raised ICP (e.g. in brain tumour patients) presumably through its effect on CBV. With the advent of slip- ring CT scanners, dynamic contrast-enhanced imaging allows for the measurement of CBV with high spatial resolution. Using a two-compartment model to characterize the distribution of X- ray contrast agent in the brain, we have developed a non- equilibrium CT method to measure CBV in normal and pathological regions. We used our method to investigate the effect of hyperventilation on CBV during propofol anaesthesia in rabbits with implanted brain tumours. Eight New Zealand White rabbits with implanted VX2 carcinoma brain tumours were studied. For each rabbit, regional CBV measurements were initially made at normocapnia (PaCO2 40 mmHg) and then at hyperventilation (PaCO2 25 mmHg) during propofol anaesthesia. The head was positioned such that a coronal image through the brain incorporated a significant cross-section of the brain tumour as well as a radial artery in a forelimb. Images at the rate of 1 per second were acquired for 2 minutes as Omnipaque 300 (1.5 ml/kg rabbit weight) was injected via a peripheral vein. In these CT images, regions of interest in the brain tissue (e.g. tumour, contra-lateral normal, and peri-tumoural) and the radial artery were drawn. For each region, the mean CT number in pre-contrast images was subtracted from the mean CT number in post-contrast images to produce either the tissue contrast concentration curve, or the arterial contrast concentration curve. Using our non- equilibrium analysis method based on a two-compartment model, regional CBV values were determined from the measured contrast concentration curves. From our study, the mean CBV values [+/- SD] in the tumour, peri-tumoural, and contra-lateral normal regions during normocapnia were: 5.47 plus or minus 1.97, 3.28 plus or minus 1.01, and 1

  16. Two-modality γ detection of blood volume by camera imaging and nonimaging stethoscope for kinetic studies of cardiovascular control in nuclear medicine

    Science.gov (United States)

    Eclancher, Bernard; Chambron, Jacques; Dumitresco, Barbu; Karman, Miklos; Pszota, Agnes; Simon, Atilla; Didon-Poncelet, Anna; Demangeat, Jean

    2002-04-01

    The quantification of rapid hemodynamic reactions to wide and slow breathing movements has been performed, by two modalities (gamma) -left ventriculography of 99mTc-labeled blood volume, in anterior oblique incidence on standing and even exercising healthy volunteers and cardiac patients. A highly sensitive stethoscope delivered whole (gamma) -counts acquired at 30 msec intervals in a square field of view including the left ventricle, in a one dimensional low resolution imaging mode for beat to beat analysis. A planar 2D (gamma) -camera imaging of the same cardiac area was then performed without cardiac gating for alternate acquisitions during deep inspiration and deep expiration, completed by a 3D MRI assessment of the stethoscope detection field. Young healthy volunteers displayed wide variations of diastolic times and stroke volumes, as a result of enhanced baroreflex control, together with +/- 16% variations of the stethoscope's background blood volume counts. Any of the components of these responses were shifted, abolished or even inverted as a result of either obesity, hypertension, aging or cardiac pathologies. The assessment of breathing control of the cardiovascular system by the beat to beat (gamma) -ventriculography combined with nuclear 2D and 3D MRI imaging is a kinetic method allowing the detection of functional anomalies in still ambulatory patients.

  17. Dual energy CT pulmonary blood volume assessment in acute pulmonary embolism - correlation with D-dimer level, right heart strain and clinical outcome

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Ralf W.; Frellesen, Claudia; Schell, Boris; Lehnert, Thomas; Jacobi, Volkmar; Vogl, Thomas J.; Kerl, J.M. [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Renker, Matthias [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Medical University of South Carolina, Heart and Vascular Center, Ashley River Tower, Charleston, SC (United States); Ackermann, Hanns [Clinic of the Goethe University, Department of Biostatistics and Mathematical Modelling, Frankfurt (Germany); Schoepf, U.J. [Medical University of South Carolina, Heart and Vascular Center, Ashley River Tower, Charleston, SC (United States)

    2011-09-15

    To investigate the role of perfusion defect (PD) size on dual energy CT pulmonary blood volume assessment as predictor of right heart strain and patient outcome and its correlation with d-dimer levels in acute pulmonary embolism (PE). 53 patients with acute PE who underwent DECT pulmonary angiography were retrospectively analyzed. Pulmonary PD size caused by PE was measured on DE iodine maps and quantified absolutely (VolPD) and relatively to the total lung volume (RelPD). Signs of right heart strain (RHS) on CT were determined. Information on d-dimer levels and readmission for recurrent onset of PE and death was collected. D-dimer level was mildly (r = 0.43-0.47) correlated with PD size. Patients with RHS had significantly higher VolPD (215 vs. 73 ml) and RelPD (9.9 vs. 2.9%) than patients without RHS (p < 0.003). There were 2 deaths and 1 readmission due of PE in 18 patients with >5% RelPD, while no such events were found for patients with <5% RelPD. Pulmonary blood volume on DECT in acute PE correlates with RHS and appears to be a predictor of patient outcome in this pilot study. (orig.)

  18. Excess molar volumes VmE, isothermal compressibilities k, and thermal expansivities α of {(1-x)H2O+xCH3OH} at T=(298.15 to 523.15) K and pressures up to 60 MPa

    International Nuclear Information System (INIS)

    The excess molar volumes VmE, isothermal compressibilities k, and thermal expansivities α of {(1-x)H2O+xCH3OH} at T =(298.15 to 523.15) K, at pressures up to 60 MPa and at x=(0.25, 0.50, and 0.75) mole fractions of methanol are reported. These properties are calculated from the experimental densities for the solutions, carried out with a constant volume piezometer over these intervals of state parameters. Calculated excess molar volumes, isothermal compressibilities, and thermal expansivities are tabulated

  19. Combined SPECT imaging of regional cerebral blood flow (99mTc-hexamethyl-propyleneamine oxime, HMPAO) and blood volume (99mTc-RBC) to assess regional cerebral perfusion reserve in patients with cerebrovascular disease

    International Nuclear Information System (INIS)

    In 53 patients with cerebrovascular disease (CDV), regional cerebral blood flow (CBF) and blood volume (CBV) were imaged by SPECT within one session. Slice division (CBF:CBV) yielded distribution of regional cerebral perfusion reserve (CPR). Semiquantitative evaluation was obtained from manually set ROIs by interhemispherical ratios (for CBF, CBV and CPR), using 2 SD from a normal group (n=10) as a threshold. Sensitivity was 59% for CBF, 94% for CBV and 83% for CPR. Combined sensitivity was 98%. Establishing three constellations for CBF, CBV and CPR, regionally normal CBFs but quantitatively increased CBVs (+69%) and decreased CPRs (-31%) were found in relatively early stages of CVD. Very advanced cases showed decreased CBFs (-65%), CBVs (-40%), CPRs (-49%) and a surrounding penumbra. In 87% (46/53 patients), such rheologically postulated constellations could be demonstrated. We conclude that combined CBF and CBV SPECT, assisted by CPR images, is a promising tool to detect CVD and to assess its individual regional severity. (orig.)

  20. Computer Aided Series Expansions for Critical Phenomena

    CERN Document Server

    Meyer-Ortmanns, H; Meyer-Ortmanns, Hildegard; Reisz, Thomas

    1996-01-01

    Under quite general conditions critical phenomena can be described with high order linked cluster expansions. The coefficients of the series admit a graphical expansion that is generated with the aid of computers. Our generalization of linked cluster expansions from an infinite to a finite volume allows to perform a finite size scaling analysis. We also indicate a generalization to Dynamical Linked Cluster Expansions with possible applications to spin glasses and neural networks with coupled spin and interaction dynamics.

  1. Spatio-temporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    Science.gov (United States)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shangbin; Chen, Haiying; Zeng, Shaoqun

    2003-10-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%)2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50%+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  2. Quantification of cellular volume and sub-cellular density fluctuations: comparison of normal peripheral blood cells and circulating tumor cells identified in a breast cancer patient

    Directory of Open Access Journals (Sweden)

    KevinGregoryPhillips

    2012-08-01

    Full Text Available Cancer metastasis, the leading cause of cancer-related deaths, is facilitated in part by the hematogenous transport of circulating tumor cells (CTCs through the vasculature. Clinical studies have demonstrated that CTCs circulate in the blood of patients with metastatic disease across the major types of carcinomas, and that the number of CTCs in peripheral blood is correlated with overall survival in metastatic breast, colorectal, and prostate cancer. While the potential to monitor metastasis through CTC enumeration exists, the basic physical features of CTCs remain ill defined and moreover, the corresponding clinical utility of these physical parameters is unknown. To elucidate the basic physical features of CTCs we present a label-free imaging technique utilizing differential interference contrast (DIC microscopy to measure cell volume and to quantify sub-cellular mass-density variations as well as the size of subcellular constituents from mass-density spatial correlations. DIC measurements were carried out on CTCs identified in a breast cancer patient using the high-definition (HD CTC detection assay. We compared the biophysical features of HD-CTC to normal blood cell subpopulations including leukocytes, platelets, and red blood cells. HD-CTCs were found to possess larger volumes, decreased mass-density fluctuations, and shorter-range spatial density correlations in comparison to leukocytes. Our results suggest that HD-CTCs exhibit biophysical signatures that might be used to potentially aid in their detection and to monitor responses to treatment in a label-free fashion. The biophysical parameters reported here can be incorporated into computational models of CTC-vascular interactions and in vitro flow models to better understand metastasis.

  3. White Blood Cell Count to Mean Platelet Volume Ratio Is a Prognostic Factor in Patients with Non-ST Elevation Acute Coronary Syndrome with or without Metabolic Syndrome

    OpenAIRE

    Dehghani, Mohammad Reza; Rezaei, Yousef; Fakour, Sanam; Arjmand, Nasim

    2016-01-01

    Background and Objectives Leukocyte and platelet have been found to be associated with metabolic syndrome (MetS). We aimed to determine the usefulness of a novel marker named white blood cell count to mean platelet volume ratio (WMR) for predicting outcomes of non-ST elevation acute coronary syndrome (NSTE-ACS) with or without MetS. Subjects and Methods A total of 331 NSTE-ACS individuals (60±12.5 years, 57.4% male) were enrolled and followed for a median of 24 months. MetS was identified usi...

  4. C-arm computed tomography parenchymal blood volume measurement in evaluation of hepatocellular carcinoma before transarterial chemoembolization with drug eluting beads

    OpenAIRE

    Syha, Roland; Grözinger, Gerd; Grosse, Ulrich; Maurer, Michael; Zender, Lars; Horger, Marius; Nikolaou, Konstantin; Ketelsen, Dominik

    2015-01-01

    Background C-arm computed tomography (CT) guided intervention is an increasingly applied technique in transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). The aim of this study was to analyse the value of parenchymal blood volume (PBV) maps acquired during C-arm CT acquisition, for pre-treatment evaluation and planning of TACE in HCC patients. Methods A total of 64 HCC lesions in 29 patients (median age, 73 years, range, 62–77 years) were included in this retrospective st...

  5. Oxidative mitochondrial DNA damage in peripheral blood mononuclear cells is associated with reduced volumes of hippocampus and subcortical gray matter in chronically HIV-infected patients

    Science.gov (United States)

    Kallianpur, Kalpana J.; Gerschenson, Mariana; Mitchell, Brooks I.; LiButti, Daniel E.; Umaki, Tracie M.; Ndhlovu, Lishomwa C.; Nakamoto, Beau K.; Chow, Dominic C.; Shikuma, Cecilia M.

    2016-01-01

    Cross-sectional relationships were examined between regional brain volumes and mitochondrial DNA (mtDNA) 8-hydroxy-2-deoxyguanosine (8-oxo-dG) in peripheral blood mononuclear cells (PBMCs) of 47 HIV patients [mean age 51 years; 81% with HIV RNA ≤50 copies/mL] on combination antiretroviral therapy. The gene-specific DNA damage and repair assay measured mtDNA 8-oxo-dG break frequency. Magnetic resonance imaging was performed at 3 T. Higher mtDNA 8-oxo-dG was associated with lateral ventricular enlargement and with decreased volumes of hippocampus, pallidum, and total subcortical gray matter, suggesting the involvement of systemic mitochondrial-specific oxidative stress in chronic HIV-related structural brain changes and cognitive difficulties. Clarification of the mechanism may provide potential therapeutic targets. PMID:26923169

  6. 每搏量变异度与单肺通气患者血容量变化的相关性%Correlation between stroke volume variation and blood volume during one-lung ventilation

    Institute of Scientific and Technical Information of China (English)

    王合梅; 李超; 雍芳芳; 贾慧群

    2012-01-01

    Objective To evaluate the correlation between stroke volume variation (SVV) and blood volume during one-lung ventilation (OLV).Methods Forty ASA Ⅱ male patients,aged 50-60 yr,with body mass index 20-25 kg/m2,scheduled for elective resection of esophageal cancer,were studied.Anesthesia was induced with fentanyl 4 μg/kg,propofol 2 mg/kg,and rocuronium 0.6 mg/kg.Double-lumen tube was inserted.Correct position was verified by fiberoptic bronchoscopy.The patients were mechanically ventilated (VT 8 ml/kg,RR 15 bpm,Ⅰ ∶ E 1 ∶ 2).6% hydroxyethyl statch (HES) 130/0.4 was infused intravenously at a rate of 0.67 ml· kg-1 · min-1 starting from 30 min of OLV.SVV,cardiac output (CO),SV and cardiac index (CI) were monitored and recorded using the FloTrac/Vigileo (Edwards Lifesciences,USA) system before HES was infused and when the dose of HES reached 2,4,6,8,10 and 12 ml/kg.Spearman rank sum correlation coefficient was used to analyze the data.Results SVV was negatively correlated with the blood volume during OLV and the correlation coefficient was rSVV =-0.249.CI,CO and SV were positively correlated with the blood volume during OLV and the correlation coefficients were rCO =0.570,rSV =0.552 and rCI =0.550,respectively.Conclusion SVV is poorly correlated with the blood volume during OLV and can not reflect the blood volume accurately.%目的 探讨每搏量变异度(Svv)与单肺通气患者血容量变化的相关性.方法 择期拟行食管癌切除术患者40例,男性,年龄50~ 60岁,体重指数20 ~ 25 kg/m2,ASA分级Ⅱ级.麻醉诱导后经口明视插入F39右侧双腔支气管导管,经两肺听诊和纤维支气管镜定位后,连接麻醉机行单肺通气,设定潮气量8 ml/kg、呼吸频率15次/min、吸呼比1∶2.单肺通气30 min时静脉输注6%羟乙基淀粉130/0.4,速率为0.67 ml· kg-1·min-1,分别在输注前、输注羟乙基淀粉剂量达2、4、6、8、10、12 ml/kg时采用FloTrac/Vigileo心输出量监测系统记录SVV、CO

  7. EFFECTS OF A BASKETBALL ACTIVITY ON LUNG CAPILLARY BLOOD VOLUME AND MEMBRANE DIFFUSING CAPACITY, MEASURED BY NO/CO TRANSFER IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Rim Dridi

    2006-09-01

    Full Text Available In both children and adults, acute exercise increases lung capillary blood volume (Vc and membrane factor (DmCO. We sought to determine whether basketball training affected this adaptation to exercise in children. The purpose of this study was to determine the effects of two years sport activity on the components of pulmonary gas transfer in children. Over a 2-yr period, we retested 60 nine year old boys who were initially separated in two groups: 30 basketball players (P (9.0 ± 1.0 yrs; 35.0 ± 5.2 kg; 1.43 ± 0.05 m, and matched non players controls (C (8.9 ± 1.0 yrs; 35.0 ± 6.0 kg; 1.44 ± 0.06 m who did not perform any extracurricular activity, Vc and DmCO were measured by the NO/CO transfer method at rest and during sub-maximal exercise. Maximal aerobic power and peak power output was 12% higher in the trained group compared to matched controls (p < 0.05. Nitric oxide lung transfer (TLNO per unit lung volume and thus, DmCO per unit of lung volume (VA were higher at rest and during exercise in the group which had undergone regular basketball activity compared to matched controls (p < 0.05. Neither lung capillary blood volume nor total lung transfer for carbon monoxide (TLCO were significantly different between groups. These results suggest that active sport can alter the properties of the lung alveolo-capillary membrane by improving alveolar membrane conductance in children

  8. Color-coded perfused blood volume imaging using multidetector CT: initial results of whole-brain perfusion analysis in acute cerebral ischemia

    International Nuclear Information System (INIS)

    Computed tomography (CT) is still the primary imaging modality following acute stroke. To evaluate a prototype of software for the calculation of color-coded whole-brain perfused blood volume (PBV) images from CT angiography (CTA) and nonenhanced CT (NECT) scans, we studied 14 patients with suspected acute ischemia of the anterior cerebral circulation. PBV calculations were performed retrospectively. The detection rate of ischemic changes in the PBV images was compared with NECT. The volume of ischemic changes in PBV was correlated with the infarct volume on follow-up examination taking potential vessel recanalization into account. PBV demonstrated ischemic changes in 12/12 patients with proven infarction and was superior to NECT (8/12) in the detection of early ischemia. Moreover, PBV demonstrated the best correlation coefficient with the follow-up infarct volume (Pearson's R = 0.957; P = 0.003) for patients with proven recanalization of initially occluded cerebral arteries. In summary, PBV appears to be more accurate in the detection of early infarction compared to NECT and mainly visualizes the irreversibly damaged ischemic tissue. (orig.)

  9. Therapeutic isolation and expansion of human skeletal muscle-derived stem cells for the use of muscle-nerve-blood vessel reconstitution

    Directory of Open Access Journals (Sweden)

    Tetsuro eTamaki

    2015-06-01

    Full Text Available Skeletal muscle makes up 40-50% of body mass, and is thus considered to be a good adult stem cell source for autologous therapy. Although, several stem/progenitor cells have been fractionated from mouse skeletal muscle showing a high potential for therapeutic use, it is unclear whether this is the case in human. Differentiation and therapeutic potential of human skeletal muscle-derived cells (Sk-Cs was examined. Samples (5-10 g were obtained from the abdominal and leg muscles of 36 patients (age, 17-79 years undergoing prostate cancer treatment or leg amputation surgery. All patients gave informed consent. Sk-Cs were isolated using conditioned collagenase solution, and were then sorted as CD34-/CD45-/CD29+ (Sk-DN/29+ and CD34+/CD45- (Sk-34 cells, in a similar manner as for the previous mouse Sk-Cs. Both cell fractions were appropriately expanded using conditioned culture medium for about 2 weeks. Differentiation potentials were then examined during cell culture and in vivo transplantation into the severely damaged muscles of athymic nude mice and rats. Interestingly, these two cell fractions could be divided into highly myogenic (Sk-DN/29+ and multipotent stem cell (Sk-34 fractions, in contrast to mouse Sk-Cs, which showed comparable capacities in both cells. At 6 weeks after the separate transplantation of both cell fractions, the former showed an active contribution to muscle fiber regeneration, but the latter showed vigorous engraftment to the interstitium associated with differentiation into Schwann cells, perineurial/endoneurial cells, and vascular endothelial cells and pericytes, which corresponded to previous observations with mouse SK-Cs. Importantly, mixed cultures of both cells resulted the reduction of tissue reconstitution capacities in vivo, whereas co-transplantation after separate expansion showed favorable results. Therefore, human Sk-Cs are potentially applicable to therapeutic autografts and show multiple differentiation

  10. Comparison between finite volume and lattice-Boltzmann method simulations of gas-fluidised beds: bed expansion and particle-fluid interaction force

    Science.gov (United States)

    Third, J. R.; Chen, Y.; Müller, C. R.

    2016-07-01

    Lattice-Boltzmann method (LBM) simulations of a gas-fluidised bed have been performed. In contrast to the current state-of-the-art coupled computational fluid dynamics-discrete element method (CFD-DEM) simulations, the LBM does not require a closure relationship for the particle-fluid interaction force. Instead, the particle-fluid interaction can be calculated directly from the detailed flow profile around the particles. Here a comparison is performed between CFD-DEM and LBM simulations of a small fluidised bed. Simulations are performed for two different values of the superficial gas velocity and it is found that the LBM predicts a larger bed expansion for both flowrates. Furthermore the particle-fluid interaction force obtained for LBM simulations is compared to the force which would be predicted by a CFD-DEM model under the same conditions. On average the force predicted by the CFD-DEM closure relationship is found to be significantly smaller than the force obtained from the LBM.

  11. Standard molar volumes and expansibilities of 1,3-alkyl-N-substituted achiral glycolurils in water at T = (278.15 to 318.15) K and p = 0.1 MPa: A comparative analysis

    International Nuclear Information System (INIS)

    Highlights: • Densities of aqueous 1,3-dimethylglycoluril and 1,3-diethylglycoluril were measured. • Densimetric measurements were carried out at T = (278.15 to 318.15) K and ∼0.1 MPa. • Standard molar volumes and expansibilities of glycolurils in water were derived. • 1,3-DMGU has the more pronounced ability to hydrogen-bonding with water molecules. • Tendency to structure-loosening in aqueous solution increases going to 1,3-DEGU. - Abstract: Densities of aqueous solutions of achiral 1,3-dimethylglycoluril (1,3-DMGU) and 1,3-diethylglycoluril (1,3-DEGU) were measured using a hermetically sealed vibrating-tube densimeter, with an uncertainty of 1 · 10−5 g · cm−3, at T = (278.15, 288.15, 298.15, 308.15, and 318.15) K and p = (99.6 ± 0.8) kPa. The solute molality was ranged from (0.06 to 0.39) and from (0.01 to 0.07) mol · kg−1 for the aqueous 1,3-DMGU and 1,3-DEGU, respectively. The standard (at infinite dilution) molar volumes and isobaric expansibilities for the 1,3-dialkyl-N-substituted glycolurils compared in water were calculated and discussed in comparison with the previously derived molar enthalpies and heat capacities of their dissolution (hydration). The temperature-dependent behavior of packing-related hydration effects was described taking into account the structural features of a solute molecule

  12. Gray matter blood flow and volume are reduced in association with white matter hyperintensity lesion burden: a cross-sectional MRI study.

    Science.gov (United States)

    Crane, David E; Black, Sandra E; Ganda, Anoop; Mikulis, David J; Nestor, Sean M; Donahue, Manus J; MacIntosh, Bradley J

    2015-01-01

    Cerebral White Matter Hyperintensities (WMH) are associated with vascular risk factors and age-related cognitive decline. WMH have primarily been associated with global white matter and gray matter (GM) changes and less is known about regional effects in GM. The purpose of this study was to test for an association between WMH and two GM imaging measures: cerebral blood flow (CBF) and voxel-based morphometry (VBM). Twenty-six elderly adults with mild to severe WMH participated in this cross-sectional 3 Tesla magnetic resonance imaging (MRI) study. MRI measures of GM CBF and VBM were derived from arterial spin labeling (ASL) and T1-weighted images, respectively. Fluid-attenuated inversion recovery (FLAIR) images were used to quantify the WMH lesion burden (mL). GM CBF and VBM data were used as dependent variables. WMH lesion burden, age and sex were used in a regression model. Visual rating of WMH with the Fazekas method was used to compare the WMH lesion volume regression approach. WMH volume was normally distributed for this group (mean volume of 22.7 mL, range: 2.2-70.6 mL). CBF analysis revealed negative associations between WMH volume and CBF in the left anterior putamen, subcallosal, accumbens, anterior caudate, orbital frontal, anterior insula, and frontal pole (corrected p lingual gyrus, intracalcarine, and bilateral hippocampus (corrected p < 0.05). The visual rating scale corroborated the regression findings (corrected p < 0.05). WMH lesion volume was associated with intra-group GM CBF and structural differences in this cohort of WMH adults with mild to severe lesion burden. PMID:26217223

  13. Xenon/CT blood flow mapping of the liver using multidetector-row computed tomography. Compensation of respiratory misregistration by volume data

    International Nuclear Information System (INIS)

    For improvement in the accuracy of xenon/CT blood flow mapping of the liver, this study was conducted to assess whether volume-data obtained by multidetector-row helical CT could compensate for the slice misregistration caused by inconstant breath depth. Using imaging phantoms scanned on both multidetector-row and single-detector CT, suitable parameters were decided. In the phantom studies, axial scan with multidetector-row CT showed significantly greater variance of CT value than that of single detector row CT (SDCT). On multidetector-row CT, variances of the CT values maintained in low (80 kV) tube voltage, which is advantageous for detecting subtle enhancement of the liver. Images reconstructed with 10-mm thickness showed smaller variance than those of 5-mm thickness on low-pitch helical scan. Remarkable helical artifacts were seen on the high-pitch helical scan. Following the phantom studies, 7 examinees were scanned using xenon/CT with a predetermined scan protocol (80 kV, collimation 5 mm, thickness 10 mm, low-pitch helical scan). In all cases, slice compensation was necessary and was successfully performed. The number of pixels which constituted blood flow map increased after the compensation. No patients showed any significant adverse effects. In conclusion, multidetector-row helical CT has the potential for providing accurate quantification of xenon/CT blood flow mapping of liver by compensating for respiratory misregistration. (author)

  14. Determinants of the renin-angiotensin-aldosterone system in cirrhosis with special emphasis on the central blood volume

    DEFF Research Database (Denmark)

    Møller, Søren; Bendtsen, Flemming; Henriksen, Jens Henrik

    2006-01-01

    dysfunction and splanchnic and systemic haemodynamics (r = - 0.56-0.55), but only weakly with CBV (r = - 0.25, p < 0.02). In a multivariate regression analysis, plasma renin was determined by serum sodium, alkaline phosphatases and systolic blood pressure (p < 0.04 to p < 0.001). CONCLUSIONS: CBV correlates...... RAAS, including the CBV. Circulating plasma renin concentrations were measured using an immunoradiometric assay. RESULTS: Arterial renin concentrations were significantly higher in the patients than in the controls (p < 0.003). Plasma renin correlated significantly with several indicators of liver...

  15. Sequence of Endothelial Signaling during Lung Expansion

    OpenAIRE

    Yiming, Maimaiti T.; Parthasarathi, Kaushik; Issekutz, Andrew C.; Bhattacharya, Sunita

    2005-01-01

    Although high tidal volume ventilation exacerbates lung injury, the mechanisms underlying the inflammatory response are not clear. Here, we exposed isolated lungs to high or low tidal volume ventilation, while perfusing lungs with whole blood, or blood depleted of leukocytes and platelets. Then, we determined signaling responses in freshly isolated lung endothelial cells by means of immunoblotting and immunofluorescence approaches. In depleted blood perfusion, high tidal volume induced modest...

  16. CORRELATION OF VOLUME BLOOD CIRCULATION IN THE HEPATIC ARTERY AND THE STATE OF MICROCIRCULATORY BLOODSTREAM OF THE TRANSPLANTED LIVER AFTER ITS REVASCULIZATION

    Directory of Open Access Journals (Sweden)

    D. A. Granov

    2014-01-01

    Full Text Available Aim: optimization of the surgical treatment policy with orthotopic liver transplantation (OLT depending on the results of intraoperative fl owmetry and the state of intrahepatic microcirculatory bloodstream according to immunohistochemical (IHC study of microspecimens of the donor’s liver.Materials and methods. 60 patients are included in the study. Group I (n = 30 comprised of patients for whom it was not necessary to perform any additional interventions on the bloodstream in the hepatopancreatobiliary area during OLT. Group II (n = 30 had patients with insuffi cient arterial blood supply for the graft in the intraoperative stage where it was needed to perform additional and/or repeated interventions in the arteries of the hepatopancreatobilliary area. Intraoperative fl owmetry with assessment of the volume blood circulation (VBC in the hepatic artery (HA was carried out in the both studied groups. Reference value of VBC was 100 ml/min and higher. Before and after reperfusion in the liver biopsy material we performed immunohistochemical study with the use of endothelial marker CD 31 with subsequent morphometric estimation of the specifi c square of the microvascular bloodstream.Results. In both groups there was no change in the specifi c square in the areas of portal tract and central vein before and after restoring blood fl ow. In the second group, an 8 times increase of the specifi c square of sinusoids was observed after restoring blood fl ow (р < 0,01.Conclusion. Intraoperative fl owmetric control of the blood fl ow allows in due time to perform surgical correction of the graft arterial blood supply during OLT, and it reduces the risk of thrombosis up to 0%. The value of VBC in the hepatic artery (HA has reliable dependence upon the state of microcirculatory bloodstream of cadaveric donor’s liver after reperfusion.

  17. Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET

    DEFF Research Database (Denmark)

    Iida, H; Law, I; Pakkenberg, B;

    2000-01-01

    onto the PET images in which regional CBF values and the water perfusable tissue fraction for the cortical gray matter tissue (hence the volume of gray matter) were estimated. After the PET study, the animals were killed and stereologic analysis was performed to assess the gray matter mass in the...... that included two parallel tissue compartments demonstrated better results with regards to the agreement of tissue time-activity curve and the Akaike's Information Criteria. Error sensitivity analysis suggested the model that fits three parameters of the gray matter CBF, the gray matter fraction, and...

  18. Propane exhaust air heat pumps with minimal refrigerant filling volume and optimised control of the electronic expansion valve; Propan-Abluft-Waermepumpe mit minimaler Kaeltemittelfuellmenge und optimierter Regelung des elektronischen Expansionsventils

    Energy Technology Data Exchange (ETDEWEB)

    Ott, S.; Frick, H. [Stiebel Eltron GmbH und Co. KG, Holzminden (Germany)

    2007-07-01

    In view of the possibly upcoming implementation of an ordinance on flammable gases in stationary refrigeration plants there is increasing interest in what are referred to as natural refrigerants. The following natural refrigerants are mainly used today: carbon dioxide (CO{sub 2}); flammable refrigerants (propane, butane, isobutane); and ammonia. In the past refrigerants classified as flammable were also used in heat pumps. However, due to poor customer acceptance and lacking support from compressor manufacturers most heat pumps have been converted to conventional refrigerants such as R134a, R404a and R407c. In order to facilitate the use of flammable refrigerants in refrigerators and freezers regulations were promulgated which specify lower requirements for the installation of refrigerant circuits with a filling volume of less than 150 g. In keeping with these specifications an exhaust air heat pump was designed with a heat capacity of 2 kW for combined water and room heating and a refrigerant filling volume of less than 150 g. The components of the refrigerant circuit were selected to allow minimal filling volume and included a refrigerator compressor. An electronic expansion valve with a purpose-designed controller was used to achieve maximum COP. This permits stable operation with minimal overheating at any operating point as well as optimal use of the evaporator. In addition the controller permits thawing control based on circuit specifications. This ensures that thawing time is kept to the necessary minimum, thus further improving COP. The present article compares the measuring results and results of a preliminary simulation with the performance of a CO{sub 2} heat pump of equal capacity.

  19. Flexible Workflow Software enables the Management of an Increased Volume and Heterogeneity of Sensors, and evolves with the Expansion of Complex Ocean Observatory Infrastructures.

    Science.gov (United States)

    Tomlin, M. C.; Jenkyns, R.

    2015-12-01

    Ocean Networks Canada (ONC) collects data from observatories in the northeast Pacific, Salish Sea, Arctic Ocean, Atlantic Ocean, and land-based sites in British Columbia. Data are streamed, collected autonomously, or transmitted via satellite from a variety of instruments. The Software Engineering group at ONC develops and maintains Oceans 2.0, an in-house software system that acquires and archives data from sensors, and makes data available to scientists, the public, government and non-government agencies. The Oceans 2.0 workflow tool was developed by ONC to manage a large volume of tasks and processes required for instrument installation, recovery and maintenance activities. Since 2013, the workflow tool has supported 70 expeditions and grown to include 30 different workflow processes for the increasing complexity of infrastructures at ONC. The workflow tool strives to keep pace with an increasing heterogeneity of sensors, connections and environments by supporting versioning of existing workflows, and allowing the creation of new processes and tasks. Despite challenges in training and gaining mutual support from multidisciplinary teams, the workflow tool has become invaluable in project management in an innovative setting. It provides a collective place to contribute to ONC's diverse projects and expeditions and encourages more repeatable processes, while promoting interactions between the multidisciplinary teams who manage various aspects of instrument development and the data they produce. The workflow tool inspires documentation of terminologies and procedures, and effectively links to other tools at ONC such as JIRA, Alfresco and Wiki. Motivated by growing sensor schemes, modes of collecting data, archiving, and data distribution at ONC, the workflow tool ensures that infrastructure is managed completely from instrument purchase to data distribution. It integrates all areas of expertise and helps fulfill ONC's mandate to offer quality data to users.

  20. Low thermal expansion glass ceramics

    CERN Document Server

    1995-01-01

    This book is one of a series reporting on international research and development activities conducted by the Schott group of companies With the series, Schott aims to provide an overview of its activities for scientists, engineers, and managers from all branches of industry worldwide where glasses and glass ceramics are of interest Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated This volume describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization Thus glass ceramics with thermal c...

  1. 不同细胞因子组合对脐血造血干细胞体外扩增效果分析%Effect of different human recombinant cytokine combinations on the expansion of cord blood haemopoietic stem cells

    Institute of Scientific and Technical Information of China (English)

    孟庆宝; 魏亚明; 张印则

    2009-01-01

    Objective To study the expansion efficiency of cord blood haemopoietic stem cells when cultured with dif-feront human recombinant cytokine combinations. Methods Mononuclear cells separated from cord blood were cultured in Iscove Modified Dulbccoo's medium(IMDM). Seven experimental groups (A——-G) were set up according to the addition of different cytokine combinations. Mononuclear cells were counted by trypan blue exclusion and the CD34+ cells were sorted by flow eytometry on the 3rd, 7th, and 14th culture day. Results Compared with the control group, the amount of mononu-clear cells in each experimental group increased significantly. Except group F, which reached the peak expansion of (15.60 ± 10. 90) × 109/L, on the 14th culture day, all other six groups showed peak expansion on the 7th day, among which group E was the highest [(17. 11±6. 12) × 109/L]. The percentage of CD34+ cells in group A, D, E, F, and G peaked on the 7th culture day, and the peak expansion in group B and C was observed on the 14th culture day. The number of CD34+ cells in unit volume among the seven groups ranged from (34. 7 ± 10. 4) × 107/L (group A) to ( 168.6 ± 43. 5 ) × 107/L (group E), with 10——50 folds of expansion. Conclusion All the experimental groups with different human re-combinant cytokine combinations could improve the expansion efficiency of cord blood mononuclear cells and CD34+ cells. The group with the combination of SCF + IL-3,-6 ,-2,-4 achieved the peak expansion on the 7th culture day.%目的 观察不同细胞因子组合对脐血干细胞体外扩增效果的影响.方法 用含15%胎牛血清的改良细胞培养液,按加入的不同细胞因子组合分成7个实验组(A-G)进行细胞培养.分别于培养0d、3d、7d、14d取培养液,台盼蓝染色计数单个核细胞的总数、流式细胞仪分析CD34+细胞含量.结果 与对照组相比,含细胞因子的7个实验组单个核细胞的数量均显著增加,除F组在培养d14

  2. Wien Automatic System Package (WASP). A computer code for power generating system expansion planning. Version WASP-III Plus. User's manual. Volume 2: Appendices

    International Nuclear Information System (INIS)

    With several Member States, the IAEA has completed a new version of the WASP program, which has been called WASP-Ill Plus since it follows quite closely the methodology of the WASP-Ill model. The major enhancements in WASP-Ill Plus with respect to the WASP-Ill version are: increase in the number of thermal fuel types (from 5 to 10); verification of which configurations generated by CONGEN have already been simulated in previous iterations with MERSIM; direct calculation of combined Loading Order of FIXSYS and VARSYS plants; simulation of system operation includes consideration of physical constraints imposed on some fuel types (i.e., fuel availability for electricity generation); extended output of the resimulation of the optimal solution; generation of a file that can be used for graphical representation of the results of the resimulation of the optimal solution and cash flows of the investment costs; calculation of cash flows allows to include the capital costs of plants firmly committed or in construction (FIXSYS plants); user control of the distribution of capital cost expenditures during the construction period (if required to be different from the general 'S' curve distribution used as default). This second volume of the document to support use of the WASP-Ill Plus computer code consists of 5 appendices giving some additional information about the WASP-Ill Plus program. Appendix A is mainly addressed to the WASP-Ill Plus system analyst and supplies some information which could help in the implementation of the program on the user computer facilities. This appendix also includes some aspects about WASP-Ill Plus that could not be treated in detail in Chapters 1 to 11. Appendix B identifies all error and warning messages that may appear in the WASP printouts and advises the user how to overcome the problem. Appendix C presents the flow charts of the programs along with a brief description of the objectives and structure of each module. Appendix D describes the

  3. Thermal expansion in lead zirconate titanate

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The volume anomalies with temperature variations in tin-modified lead zirconate titanate ceramics are investigated. Experimental results show that the volume changes are related to the phase transitions induced with temperature. The magnitude and orientation of crystal volume changes are dependent on the particular phase transition. When antiferroelectrics is transformed to ferroelectrics or paraelectrics the volume expands. Oppositely when ferroelectrics is transformed to antiferroelectrics or paraelectrics the volume contracts. In the transition of antiferroelectric orthorhombic structure to tetragonal structure or ferroelectric low-temperature rhombohedral structure to high-tem- perature rhombohedral structure, there are also revealed apparent anomalies in the curves of thermal expansion. Among them, the volume strain caused by the transition between antiferroelectrics and ferroelectrics is the biggest in magnitude, and the linear expansion dL/L0 and the expansion coefficient (dL/L0)/dT can reach 2.810?3 and 7.5 × 10?4 K?1 respectively.

  4. Large volume injection of 1-octanol as sample diluent in reversed phase liquid chromatography: application in bioanalysis for assaying of indapamide in whole blood.

    Science.gov (United States)

    Udrescu, Stefan; Sora, Iulia Daniela; Albu, Florin; David, Victor; Medvedovici, Andrei

    2011-04-01

    Large volume injection of samples in strong diluents immiscible with the mobile phases used in reversed phase liquid chromatography (RPLC) has been recently introduced in practice. In the present work, the potential of the technique has been evaluated for bioanalytical applications. The process consists of the liquid-liquid extraction of indapamide from whole blood into 1-octanol, followed by the direct injection from the organic layer into the LC. Detection was made through negative electrospray ionization (ESI) and tandem mass spectrometry (MS(2)). The method was developed, validated, and successfully applied to a large number of samples in two bioequivalence studies designed for indapamide 1.5mg sustained release and 2.5mg immediate release pharmaceutical formulations. The performance of the analytical method is discussed based on data resulting from the validation procedure and the completion of the bioequivalence studies. PMID:21195573

  5. Effects of electrostimulation on the vastus medialis in the deoxygenation and the blood volume signals obtained by near-infrared spectroscopy

    Science.gov (United States)

    Verdaguer-Codina, Joan

    1996-12-01

    The electrotherapy field has been generated as a technique to improve the muscles of people affected by various pathologies. For this reason the electrotherapy is increasing its use as part of a treatment in muscle therapy. However there are not studies related to electrostimulation and near-IR spectroscopy. This work was designed to assess by near-IR spectroscopy the effects of electrostimulation in the vastus medialis, applying a tetanic contraction in this muscle with a compensated rectangular impulse at 100Hz, tolerating the subject 10mA of current. In the results obtained, we have not observed significant variations in the deoxygenation and blood volume signals, whereas as light change was observed comparing the calibration signals before and after to apply electrostimulation. It is postulated that electrostimulation only increases the diameter of the vessels, because the muscle doesn't do a metabolic work, and the heart rate frequency of the subject has not increased.

  6. Correlation between tumor size and blood volume in lung tumors: a prospective study on dual-energy gemstone spectral CT imaging.

    Science.gov (United States)

    Aoki, Masahiko; Takai, Yoshihiro; Narita, Yuichiro; Hirose, Katsumi; Sato, Mariko; Akimoto, Hiroyoshi; Kawaguchi, Hideo; Hatayama, Yoshiomi; Miura, Hiroyuki; Ono, Shuichi

    2014-09-01

    The purpose of this study was to investigate the relationship between tumor size and blood volume for patients with lung tumors, using dual-energy computed tomography (DECT) and a gemstone spectral imaging (GSI) viewer. During the period from March 2011 to March 2013, 50 patients with 57 medically inoperable lung tumors underwent DECT before stereotactic body radiotherapy (SBRT) of 50-60 Gy in 5-6 fractions. DECT was taken for pretreatment evaluation. The region-of-interest for a given spatial placement of the tumors was set, and averages for CT value, water density and iodine density were compared with tumor size. The average values for iodine density in tumors of ≤ 2 cm, 2-3 cm, and >3 cm maximum diameter were 24.7, 19.6 and 16.0 (100 µg/cm(3)), respectively. The average value of the iodine density was significantly lower in larger tumors. No significant correlation was detected between tumor size and average CT value or between tumor size and average water density. Both the average water density and the average CT value were affected by the amount of air in the tumor, but the average iodine density was not affected by air in the tumor. The average water density and the average CT value were significantly correlated, but the average iodine density and the average CT value showed no significant correlation. The blood volume of tumors can be indicated by the average iodine density more accurately than it can by the average CT value. The average iodine density as assessed by DECT might be a non-invasive and quantitative assessment of the radio-resistance ascribable to the hypoxic cell population in a tumor. PMID:24829253

  7. Correlation between tumor size and blood volume in lung tumors. A prospective study on dual-energy gemstone spectral CT imaging

    International Nuclear Information System (INIS)

    The purpose of this study was to investigate the relationship between tumor size and blood volume for patients with lung tumors, using dual-energy computed tomography (DECT) and a gemstone spectral imaging (GSI) viewer. During the period from March 2011 to March 2013, 50 patients with 57 medically inoperable lung tumors underwent DECT before stereotactic body radiotherapy (SBRT) of 50-60 Gy in 5-6 fractions. DECT was taken for pretreatment evaluation. The region-of-interest for a given spatial placement of the tumors was set, and averages for CT value, water density and iodine density were compared with tumor size. The average values for iodine density in tumors of ≤ 2 cm, 2-3 cm, and > 3 cm maximum diameter were 24.7, 19.6 and 16.0 (100 μg/cm3), respectively. The average value of the iodine density was significantly lower in larger tumors. No significant correlation was detected between tumor size and average CT value or between tumor size and average water density. Both the average water density and the average CT value were affected by the amount of air in the tumor, but the average iodine density was not affected by air in the tumor. The average water density and the average CT value were significantly correlated, but the average iodine density and the average CT value showed no significant correlation. The blood volume of tumors can be indicated by the average iodine density more accurately than it can by the average CT value. The average iodine density as assessed by DECT might be a non-invasive and quantitative assessment of the radio-resistance ascribable to the hypoxic cell population in a tumor. (author)

  8. SU-E-J-241: Wavelet-Based Temporal Feature Extraction From DCE-MRI to Identify Sub-Volumes of Low Blood Volume in Head-And-Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    You, D; Aryal, M; Samuels, S; Eisbruch, A; Cao, Y [University of Michigan, Ann Arbor, MI (United States)

    2015-06-15

    Purpose: A previous study showed that large sub-volumes of tumor with low blood volume (BV) (poorly perfused) in head-and-neck (HN) cancers are significantly associated with local-regional failure (LRF) after chemoradiation therapy, and could be targeted with intensified radiation doses. This study aimed to develop an automated and scalable model to extract voxel-wise contrast-enhanced temporal features of dynamic contrastenhanced (DCE) MRI in HN cancers for predicting LRF. Methods: Our model development consists of training and testing stages. The training stage includes preprocessing of individual-voxel DCE curves from tumors for intensity normalization and temporal alignment, temporal feature extraction from the curves, feature selection, and training classifiers. For feature extraction, multiresolution Haar discrete wavelet transformation is applied to each DCE curve to capture temporal contrast-enhanced features. The wavelet coefficients as feature vectors are selected. Support vector machine classifiers are trained to classify tumor voxels having either low or high BV, for which a BV threshold of 7.6% is previously established and used as ground truth. The model is tested by a new dataset. The voxel-wise DCE curves for training and testing were from 14 and 8 patients, respectively. A posterior probability map of the low BV class was created to examine the tumor sub-volume classification. Voxel-wise classification accuracy was computed to evaluate performance of the model. Results: Average classification accuracies were 87.2% for training (10-fold crossvalidation) and 82.5% for testing. The lowest and highest accuracies (patient-wise) were 68.7% and 96.4%, respectively. Posterior probability maps of the low BV class showed the sub-volumes extracted by our model similar to ones defined by the BV maps with most misclassifications occurred near the sub-volume boundaries. Conclusion: This model could be valuable to support adaptive clinical trials with further

  9. The reproducibility of left ventricular volume and mass measurements: a comparison between dual-inversion-recovery black-blood sequence and SSFP

    International Nuclear Information System (INIS)

    The aim of this study was to compare a dual-inversion-recovery black-blood (BB) magnetic resonance imaging (MRI) sequence with steady-state free precession (SSFP) for the assessment of left ventricular parameters. The improved endocardial border definition seen with SSFP was not observed at the epicardial border. Improvements in segmentation at the left ventricular epicardial border have been observed with this black-blood sequence. Left ventricular (LV) mass and LV end-diastolic volume (EDV) measurements as well as inter-observer and intra-observer variability were compared between images acquired with a dual inversion BB and SSFP sequence. The mean±1 standard deviation (SD) for LV EDV was 178.3±52.7 ml measured with SSFP and 158.8±62.2 ml with BB. This difference was not statistically significant (p=0.22). For SSFP, the mean value of LV mass was 124.0±27.0 g and 147.5±37.4 g for BB, a statistically significant difference (p<0.0001). The dual-inversion-recovery BB imaging showed improved reproducibility for LV mass measurements compared with SSFP and improved spatial resolution. For studies requiring LV mass measurements, the dual-inversion-recovery BB sequence offers improved spatial resolution and improved reproducibility to SSFP. (orig.)

  10. Cerebral blood flow volume measurements of the carotid artery and ipsilateral branches using two-dimensional phase-contrast magnetic resonance angiography

    Institute of Scientific and Technical Information of China (English)

    Gang Guo; Yonggui Yang; Weiqun Yang

    2011-01-01

    The optimal velocity encoding of phase-contrast magnetic resonance angiography (PC MRA) in measuring cerebral blood flow volume (BFV) ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional (2D) PC MRA, the present study localized the region of interest at blood vessels of the neck using PC MRA based on three-dimensional time-of-flight sequences, and the velocity encodingwas set to 80 cm/s. Results of the measurements showed that the error rate was 7.0 ± 6.0%in the estimation of BFV in the internal carotid artery, the external carotid artery and the ipsilateralcommon carotid artery. There was no significant difference, and a significant correlation in BFV between internal carotid artery + external carotid artery and ipsilateral common carotid artery. Inaddition, the BFV of the common carotid artery was correlated with that of the ipsilateral internal carotid artery. The main error was attributed to the external carotid artery and its branches. Therefore,after selecting the appropriate scanning parameters and protocols, 2D PC MRA is more accuratein the determination of BFV in the carotid arteries.

  11. MR vascular fingerprinting: A new approach to compute cerebral blood volume, mean vessel radius, and oxygenation maps in the human brain.

    Science.gov (United States)

    Christen, T; Pannetier, N A; Ni, W W; Qiu, D; Moseley, M E; Schuff, N; Zaharchuk, G

    2014-04-01

    In the present study, we describe a fingerprinting approach to analyze the time evolution of the MR signal and retrieve quantitative information about the microvascular network. We used a Gradient Echo Sampling of the Free Induction Decay and Spin Echo (GESFIDE) sequence and defined a fingerprint as the ratio of signals acquired pre- and post-injection of an iron-based contrast agent. We then simulated the same experiment with an advanced numerical tool that takes a virtual voxel containing blood vessels as input, then computes microscopic magnetic fields and water diffusion effects, and eventually derives the expected MR signal evolution. The parameter inputs of the simulations (cerebral blood volume [CBV], mean vessel radius [R], and blood oxygen saturation [SO2]) were varied to obtain a dictionary of all possible signal evolutions. The best fit between the observed fingerprint and the dictionary was then determined by using least square minimization. This approach was evaluated in 5 normal subjects and the results were compared to those obtained by using more conventional MR methods, steady-state contrast imaging for CBV and R and a global measure of oxygenation obtained from the superior sagittal sinus for SO2. The fingerprinting method enabled the creation of high-resolution parametric maps of the microvascular network showing expected contrast and fine details. Numerical values in gray matter (CBV=3.1±0.7%, R=12.6±2.4μm, SO2=59.5±4.7%) are consistent with literature reports and correlated with conventional MR approaches. SO2 values in white matter (53.0±4.0%) were slightly lower than expected. Numerous improvements can easily be made and the method should be useful to study brain pathologies. PMID:24321559

  12. Simultaneous evaluation of brain tumour metabolism, structure and blood volume using [18F]-fluoroethyltyrosine (FET) PET/MRI: feasibility, agreement and initial experience

    International Nuclear Information System (INIS)

    Both [18F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of simultaneous structural MRI, BV MRI and FET PET of gliomas using an integrated PET/MRI scanner and to assess the spatial and quantitative agreement in tumour imaging between BV MRI and FET PET. A total of 32 glioma patients underwent a 20-min static simultaneous PET/MRI acquisition on a Siemens mMR system 20 min after injection of 200 MBq FET. The MRI protocol included standard structural MRI and dynamic susceptibility contrast (DSC) imaging for BV measurements. Maximal relative tumour FET uptake (TBRmax) and BV (rBVmax), and Dice coefficients were calculated to assess the quantitative and spatial congruence in the tumour volumes determined by FET PET, BV MRI and contrast-enhanced MRI. FET volume and TBRmax were higher in BV-positive than in BV-negative scans, and both VOLBV and rBVmax were higher in FET-positive than in FET-negative scans. TBRmax and rBVmax were positively correlated (R2 = 0.59, p < 0.001). FET and BV positivity were in agreement in only 26 of the 32 patients and in 42 of 63 lesions, and spatial congruence in the tumour volumes as assessed by the Dice coefficients was generally poor with median Dice coefficients exceeding 0.1 in less than half the patients positive on at least one modality for any pair of modalities. In 56 % of the patients susceptibility artefacts in DSC BV maps overlapped the tumour on MRI. The study demonstrated that although tumour volumes determined by BV MRI and FET PET were quantitatively correlated, their spatial congruence in a mixed population of treated glioma patients was generally poor, and the modalities did not provide the same information in this population of patients. Combined imaging of brain tumour metabolism and perfusion using

  13. Simultaneous evaluation of brain tumour metabolism, structure and blood volume using [{sup 18}F]-fluoroethyltyrosine (FET) PET/MRI: feasibility, agreement and initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, Otto M.; Hansen, Adam E.; Law, Ian [Copenhagen University Hospital Rigshospitalet Blegdamsvej, Department of Clinical Physiology Nuclear Medicine and PET, Copenhagen (Denmark); Larsen, Vibeke A. [Copenhagen University Hospital Rigshospitalet Blegdamsvej, Department of Radiology, Copenhagen (Denmark); Muhic, Aida; Poulsen, Hans S. [Copenhagen University Hospital Rigshospitalet Blegdamsvej, Department of Oncology, Copenhagen (Denmark); Larsson, Henrik B.W. [Copenhagen University Hospital Rigshospitalet Glostrup, Functional Imaging Unit, Department of Clinical Physiology Nuclear Medicine and PET, Glostrup (Denmark)

    2016-01-15

    Both [{sup 18}F]-fluoroethyltyrosine (FET) PET and blood volume (BV) MRI supplement routine T1-weighted contrast-enhanced MRI in gliomas, but whether the two modalities provide identical or complementary information is unresolved. The aims of the study were to investigate the feasibility of simultaneous structural MRI, BV MRI and FET PET of gliomas using an integrated PET/MRI scanner and to assess the spatial and quantitative agreement in tumour imaging between BV MRI and FET PET. A total of 32 glioma patients underwent a 20-min static simultaneous PET/MRI acquisition on a Siemens mMR system 20 min after injection of 200 MBq FET. The MRI protocol included standard structural MRI and dynamic susceptibility contrast (DSC) imaging for BV measurements. Maximal relative tumour FET uptake (TBR{sub max}) and BV (rBV{sub max}), and Dice coefficients were calculated to assess the quantitative and spatial congruence in the tumour volumes determined by FET PET, BV MRI and contrast-enhanced MRI. FET volume and TBR{sub max} were higher in BV-positive than in BV-negative scans, and both VOL{sub BV} and rBV{sub max} were higher in FET-positive than in FET-negative scans. TBR{sub max} and rBV{sub max} were positively correlated (R{sup 2} = 0.59, p < 0.001). FET and BV positivity were in agreement in only 26 of the 32 patients and in 42 of 63 lesions, and spatial congruence in the tumour volumes as assessed by the Dice coefficients was generally poor with median Dice coefficients exceeding 0.1 in less than half the patients positive on at least one modality for any pair of modalities. In 56 % of the patients susceptibility artefacts in DSC BV maps overlapped the tumour on MRI. The study demonstrated that although tumour volumes determined by BV MRI and FET PET were quantitatively correlated, their spatial congruence in a mixed population of treated glioma patients was generally poor, and the modalities did not provide the same information in this population of patients. Combined

  14. Lower Hemoglobin Correlates with Larger Stroke Volumes in Acute Ischemic Stroke

    OpenAIRE

    Kimberly, W. Taylor; Wu, Ona; Arsava, E. Murat; Garg, Priya; Ji, Ruijun; Vangel, Mark; Singhal, Aneesh B; Ay, Hakan; Sorensen, A. Gregory

    2011-01-01

    Background Hemoglobin tetramers are the major oxygen-carrying molecules within the blood. We hypothesized that a lower hemoglobin level and its reduced oxygen-carrying capacity would associate with larger infarction in acute ischemic stroke patients. Methods We studied 135 consecutive patients with acute ischemic stroke and perfusion brain MRI. We explored the association of admission hemoglobin with initial infarct volumes on acute images and the volume of infarct expansion on follow-up imag...

  15. Thermal Expansion of Polyurethane Foam

    Science.gov (United States)

    Lerch, Bradley A.; Sullivan, Roy M.

    2006-01-01

    Closed cell foams are often used for thermal insulation. In the case of the Space Shuttle, the External Tank uses several thermal protection systems to maintain the temperature of the cryogenic fuels. A few of these systems are polyurethane, closed cell foams. In an attempt to better understand the foam behavior on the tank, we are in the process of developing and improving thermal-mechanical models for the foams. These models will start at the microstructural level and progress to the overall structural behavior of the foams on the tank. One of the key properties for model characterization and verification is thermal expansion. Since the foam is not a material, but a structure, the modeling of the expansion is complex. It is also exacerbated by the anisoptropy of the material. During the spraying and foaming process, the cells become elongated in the rise direction and this imparts different properties in the rise direction than in the transverse directions. Our approach is to treat the foam as a two part structure consisting of the polymeric cell structure and the gas inside the cells. The polymeric skeleton has a thermal expansion of its own which is derived from the basic polymer chemistry. However, a major contributor to the thermal expansion is the volume change associated with the gas inside of the closed cells. As this gas expands it exerts pressure on the cell walls and changes the shape and size of the cells. The amount that this occurs depends on the elastic and viscoplastic properties of the polymer skeleton. The more compliant the polymeric skeleton, the more influence the gas pressure has on the expansion. An additional influence on the expansion process is that the polymeric skeleton begins to breakdown at elevated temperatures and releases additional gas species into the cell interiors, adding to the gas pressure. The fact that this is such a complex process makes thermal expansion ideal for testing the models. This report focuses on the thermal

  16. Measurements of diagnostic examination performance and correlation analysis using microvascular leakage, cerebral blood volume, and blood flow derived from 3T dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging in glial tumor grading

    International Nuclear Information System (INIS)

    To assess the diagnostic accuracy of microvascular leakage (MVL), cerebral blood volume (CBV) and blood flow (CBF) values derived from dynamic susceptibility-weighted contrast-enhanced perfusion MR imaging (DSC-MR imaging) for grading of cerebral glial tumors, and to estimate the correlation between vascular permeability/perfusion parameters and tumor grades. A prospective study of 79 patients with cerebral glial tumors underwent DSC-MR imaging. Normalized relative CBV (rCBV) and relative CBF (rCBF) from tumoral (rCBVt and rCBFt), peri-enhancing region (rCBVe and rCBFe), and the value in the tumor divided by the value in the peri-enhancing region (rCBVt/e and rCBFt/e), as well as MVL, expressed as the leakage coefficient K2 were calculated. Hemodynamic variables and tumor grades were analyzed statistically and with Pearson correlations. Receiver operating characteristic (ROC) curve analyses were also performed for each of the variables. The differences in rCBVt and the maximum MVL (MVLmax) values were statistically significant among all tumor grades. Correlation analysis using Pearson was as follows: rCBVt and tumor grade, r = 0.774; rCBFt and tumor grade, r = 0.417; MVLmax and tumor grade, r = 0.559; MVLmax and rCBVt, r = 0.440; MVLmax and rCBFt, r = 0.192; and rCBVt and rCBFt, r = 0.605. According to ROC analyses for distinguishing tumor grade, rCBVt showed the largest areas under ROC curve (AUC), except for grade III from IV. Both rCBVt and MVLmax showed good discriminative power in distinguishing all tumor grades. rCBVt correlated strongly with tumor grade; the correlation between MVLmax and tumor grade was moderate. (orig.)

  17. Factors influencing electric utility expansion. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    Masud, E. [ed.

    1977-01-01

    This report, Vol. 2, submitted by the General Electric Co., identifies factors that should be considered in planning interconnected systems and discusses how these factors relate to one another. The objective is to identify all the factors and classify them by their use and importance in arriving at a decision. Chapter 2 discusses the utility system and its system behavior characteristics, emphasizing behavior that affects the planning of the bulk-power generation and transmission system. Chapter 3 introduces interconnection planning by discussing the new system characteristics brought to operation and planning. Forty-two factors associated with cost, reliability, constraints, and coordination are related to each other by factor trees. Factor trees display the relationship of one factor such as reliability to more-detailed factors which in turn are further related to individual characteristics of facilities. These factor trees provide a structure to the presentation. A questionnaire including the 42 factors was completed by 52 system planners from utility companies and government authorities. The results of these questionnaires are tabulated and presented with pertinent discussion of each factor. Chapter 4 deals with generation planning, recognizing the existence of interconnections. Chapter 5 addresses transmission planning, questions related to reliability and cost measures and constraints, and factors related to both analytical techniques and planning procedures. The chapter ends with a discussion of combined generation-transmission planning. (MCW)

  18. Saline-induced natriuresis and renal blood flow in conscious dogs: effects of sodium infusion rate and concentration

    DEFF Research Database (Denmark)

    Sandgaard, N C F; Andersen, J L; Holstein-Rathlou, N-H;

    2005-01-01

    AIM: This study focused on static and dynamic changes in total renal blood flow (RBF) during volume expansion and tested whether a change in RBF characteristics is a necessary effector mechanism in saline-induced natriuresis. METHODS: The aortic flow subtraction technique was used to measure RBF ...

  19. Relationship between ischemic ST depression pattern and coronary blood volume. Study using [sup 13]NH[sub 3] positron emission computed tomography under light exercise

    Energy Technology Data Exchange (ETDEWEB)

    Watabe, Takuya; Okazaki, Osamu; Michihata, Tetsuo; Hara, Toshihiko; Harumi, Kenichi (National Nakano Hospital, Tokyo (Japan)); Akutsu, Yasushi; Yamanaka, Hideyuki; Katagiri, Takashi

    1994-09-01

    To determine the relationship between ST depression pattern and coronary blood volume in exercise induced myocardial ischemia, exercise-induced ST changes on ECG and regional myocardial blood flow (RMBF) on positron emission computed tomography (PET) were examined. The subjects were 41 patients with myocardial infarction and 30 with angina pectoris, consisting of 55 men and 16 women. Five normal men served as controls. In the group of ST depression, maximum PRP and age were significantly high, and patients with multiple vessel disease accounted for 63.6%. RMBF, as shown on PET, increased by 10% or more after exercise in 71.1% in the group of non ST change and in the control group. In 60.6% of the patients having ST depression, there was a decrease in RMBF or an unfavorable increase in RMBF. Among 33 patients in the group of ST depression, 17 had a sagging type. Of these 17, 12 (70.6%) showed a decrease of RMBF or an unfavorable increase in RMBF, and 10 had triple vessel disease. Sixteen patients had a horizontal type, 8 of whom (50.0%) had a decrease or unfavorable increase in RMBF. These findings suggest that a decrease or unfavorable increase (an increased rate of 10% or less) may be involved in the occurrence of ST depression induced by exercise. In particular, patients with a sagging type ST depression should be monitored during exercise because many of these patients may have triple vessel disease and a decrease or unfavorable increase in RMBF. (N.K.).

  20. Relationship between ischemic ST depression pattern and coronary blood volume. Study using 13NH3 positron emission computed tomography under light exercise

    International Nuclear Information System (INIS)

    To determine the relationship between ST depression pattern and coronary blood volume in exercise induced myocardial ischemia, exercise-induced ST changes on ECG and regional myocardial blood flow (RMBF) on positron emission computed tomography (PET) were examined. The subjects were 41 patients with myocardial infarction and 30 with angina pectoris, consisting of 55 men and 16 women. Five normal men served as controls. In the group of ST depression, maximum PRP and age were significantly high, and patients with multiple vessel disease accounted for 63.6%. RMBF, as shown on PET, increased by 10% or more after exercise in 71.1% in the group of non ST change and in the control group. In 60.6% of the patients having ST depression, there was a decrease in RMBF or an unfavorable increase in RMBF. Among 33 patients in the group of ST depression, 17 had a sagging type. Of these 17, 12 (70.6%) showed a decrease of RMBF or an unfavorable increase in RMBF, and 10 had triple vessel disease. Sixteen patients had a horizontal type, 8 of whom (50.0%) had a decrease or unfavorable increase in RMBF. These findings suggest that a decrease or unfavorable increase (an increased rate of 10% or less) may be involved in the occurrence of ST depression induced by exercise. In particular, patients with a sagging type ST depression should be monitored during exercise because many of these patients may have triple vessel disease and a decrease or unfavorable increase in RMBF. (N.K.)

  1. Low Thermal Expansion Glass Ceramics

    CERN Document Server

    Bach, Hans

    2005-01-01

    This book appears in the authoritative series reporting the international research and development activities conducted by the Schott group of companies. This series provides an overview of Schott's activities for scientists, engineers, and managers from all branches of industry worldwide in which glasses and glass ceramics are of interest. Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated. This new extended edition describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics. The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions. Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization. Thus g...

  2. Effect of steroid on brain tumors and surround edemas : observation with regional cerebral blood volume (rCBV) maps of perfusion MRI

    International Nuclear Information System (INIS)

    To observe the hemodynamic change in brain tumors and peritumoral edemas after steroid treatment, and then investigate the clinical usefulness of perfusion MRI. We acquired conventional and perfusion MR images in 15 patients with various intracranial tumors (4 glioblastoma multiformes, 4 meningiomas, 3 metastatic tumors, 1 anaplastic ependymoma, 1 anaplastic astrocytoma, 1 hemangioblastoma, and 1 pilocytic astrocytoma). For perfusion MR imaging, a 1.5T unit employing the gradient-echo EPI technique was used, and further perfusion MR images were obtained 2-10 days after intravenous steroid therapy. After processing of the raw data, regional cerebral blood volume (rCBV) maps were reconstructed. The maps were visually evaluated by comparing relative perfusion in brain tumors and peritumoral edemas with that in contralateral white matter. Objective evaluations were performed by comparing the perfusion ratios of brain tumors and peritumoral edemas. Visual evaluations of rCBV maps, showed that in most brain tumors (67%, 10/15), perfusion was high before steroid treatment and showed in (80%, 12/15) decreased afterwards. Objective evaluation, showed that in all brain tumors, perfusion decreased. Visual evaluation of perfusion change in peritumoral edemas revealed change in only one case, but objective evaluation indicated that perfusion decreased significantly in all seven cases. rCBV maps acquired by perfusion MR imaging can provide hemodynamic information about brain tumors and peritumoral edemas. Such maps could prove helpful in the preoperative planning of brain tumor surgery and the monitoring of steroid effects during conservative treatment. (author)

  3. Membrane diffusion- and capillary blood volume measurements are not useful as screening tools for pulmonary arterial hypertension in systemic sclerosis: a case control study

    Directory of Open Access Journals (Sweden)

    Spreeuwenberg Marieke D

    2008-10-01

    Full Text Available Abstract Background There is no optimal screening tool for the assessment of pulmonary arterial hypertension (PAH in patients with systemic sclerosis (SSc. A decreasing transfer factor of the lung for CO (TLCO is associated with the development of PAH in SSc. TLCO can be partitioned into the diffusion of the alveolar capillary membrane (Dm and the capillary blood volume (Vc. The use of the partitioned diffusion to detect PAH in SSc is not well established yet. This study evaluates whether Dm and Vc could be candidates for further study of the use for screening for PAH in SSc. Methods Eleven SSc patients with PAH (SScPAH+, 13 SSc patients without PAH (SScPAH- and 10 healthy control subjects were included. Pulmonary function testing took place at diagnosis of PAH. TLCO was partitioned according to Roughton and Forster. As pulmonary fibrosis in SSc influences values of the (partitioned TLCO, these were adjusted for fibrosis score as assessed on HRCT. Results TLCO as percentage of predicted (% was lower in SScPAH+ than in SScPAH- (41 ± 7% vs. 63 ± 12%, p vs. 39 ± 12%, p Conclusion SScPAH+ patients have lower Dm% than SScPAH- patients. There are no correlations between Dm% and hemodynamic parameters of PAH in SScPAH+. These findings do not support further study of the role of partitioning TLCO in the diagnostic work- up for PAH in SSc.

  4. Effect of steroid on brain tumors and surround edemas : observation with regional cerebral blood volume (rCBV) maps of perfusion MRI

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ju Youl; Sun, Joo Sung; Kim, Sun Yong; Kim, Ji Hyung; Suh, Jung Ho; Cho, Kyung Gi; Kim, Jang Sung [Ajou University, School of Medicine, Su won (Korea, Republic of)

    2000-01-01

    To observe the hemodynamic change in brain tumors and peritumoral edemas after steroid treatment, and then investigate the clinical usefulness of perfusion MRI. We acquired conventional and perfusion MR images in 15 patients with various intracranial tumors (4 glioblastoma multiformes, 4 meningiomas, 3 metastatic tumors, 1 anaplastic ependymoma, 1 anaplastic astrocytoma, 1 hemangioblastoma, and 1 pilocytic astrocytoma). For perfusion MR imaging, a 1.5T unit employing the gradient-echo EPI technique was used, and further perfusion MR images were obtained 2-10 days after intravenous steroid therapy. After processing of the raw data, regional cerebral blood volume (rCBV) maps were reconstructed. The maps were visually evaluated by comparing relative perfusion in brain tumors and peritumoral edemas with that in contralateral white matter. Objective evaluations were performed by comparing the perfusion ratios of brain tumors and peritumoral edemas. Visual evaluations of rCBV maps, showed that in most brain tumors (67%, 10/15), perfusion was high before steroid treatment and showed in (80%, 12/15) decreased afterwards. Objective evaluation, showed that in all brain tumors, perfusion decreased. Visual evaluation of perfusion change in peritumoral edemas revealed change in only one case, but objective evaluation indicated that perfusion decreased significantly in all seven cases. rCBV maps acquired by perfusion MR imaging can provide hemodynamic information about brain tumors and peritumoral edemas. Such maps could prove helpful in the preoperative planning of brain tumor surgery and the monitoring of steroid effects during conservative treatment. (author)

  5. Shrinkage and Expansive Strain of Concrete with Fly Ash and Expansive Agent

    Institute of Scientific and Technical Information of China (English)

    GAO Peiwei; LU Xiaolin; TANG Mingshu

    2009-01-01

    The effects of fly ash and MgO-type expansive agent on the shrinkage and expan-sive strain of concrete with high magnesia cement were investigated. The results show that high volumes of fly ash may reduce the shrinkage strain of concrete and inhibit the expansive strain of concrete with MgO-type expansive agent, but can not eliminate the shrinkage of concrete. MgO-type expansive agent may produce expansive strain and compensate the shrinkage strain of concrete, re-lieve the cracking risk, but the hydration product of magnesia tends to get together in paste and pro-duce expansive cracking of concrete with high magnesia content according to SEM observation.

  6. The Thermal Expansion Of Feldspars

    Science.gov (United States)

    Hovis, G. L.; Medford, A.; Conlon, M.

    2009-12-01

    Hovis and others (1) investigated the thermal expansion of natural and synthetic AlSi3 feldspars and demonstrated that the coefficient of thermal expansion (α) decreases significantly, and linearly, with increasing room-temperature volume (VRT). In all such feldspars, therefore, chemical expansion limits thermal expansion. The scope of this work now has been broadened to include plagioclase and Ba-K feldspar crystalline solutions. X-ray powder diffraction data have been collected between room temperature and 925 °C on six plagioclase specimens ranging in composition from anorthite to oligoclase. When combined with thermal expansion data for albite (2,3,4) a steep linear trend of α as a function of VRT emerges, reflecting how small changes in composition dramatically affect expansion behavior. The thermal expansion data for five synthetic Ba-K feldspars ranging in composition from 20 to 100 mole percent celsian, combined with data for pure K-feldspar (3,4), show α-VRT relationships similar in nature to the plagioclase series, but with a slope and intercept different from the latter. Taken as a group all Al2Si2 feldspars, including anorthite and celsian from the present study along with Sr- (5) and Pb-feldspar (6) from other workers, show very limited thermal expansion that, unlike AlSi3 feldspars, has little dependence on the divalent-ion (or M-) site occupant. This apparently is due to the necessitated alternation of Al and Si in the tetrahedral sites of these minerals (7), which in turn locks the tetrahedral framework and makes the M-site occupant nearly irrelevant to expansion behavior. Indeed, in feldspar series with coupled chemical substitution it is the change away from a 1:1 Al:Si ratio that gives feldspars greater freedom to expand. Overall, the relationships among α, chemical composition, and room-temperature volume provide useful predictive tools for estimating feldspar thermal expansion and give insight into the controls of expansion behavior in

  7. Reliability of perfusion MR imaging in symptomatic carotid occlusive disease. Cerebral blood volume, mean transit time and time-to-peak

    International Nuclear Information System (INIS)

    Purpose: Perfusion MR imaging offers an easy quantitative evaluation of relative regional cerebral blood volume (rrCBV), relative mean transit time (rMTT) and time-to-peak (TTP). The purpose of this study was to investigate the reliability of these parameters in assessing the hemodynamic disturbance of carotid occlusive disease in comparison with normative data. Material and Methods: Dynamic contrast-enhanced T2*-weighted perfusion MR imaging was performed in 19 patients with symptomatic unilateral internal carotid artery occlusion and 20 control subjects. The three parameters were calculated from the concentration-time curve fitted by gamma-variate function. Lesion-to-contralateral ratios of each parameter were compared between patients and control subjects. Results: Mean±SD of rrCBV, rMTT and TTP ratios of patients were 1.089±0.118, 1.054±0.031 and 1.062±0.039, respectively, and those of control subjects were 1.002±0.045, 1.000±0.006, 1.001±0.006, respectively. The rMTT and TTP ratios of all patients were greater than 2SDs of control data, whereas in only 6 patients (32%), rrCBV ratios were greater than 2SDs of control data. The three parameter ratios of the patients were significantly high compared with those of control subjects, respectively (p<0.01 for rrCBV ratios, p<0.0001 for rMTT ratios, and p<0.0001 for TTP ratios). Conclusion: Our results indicate that rMTT and TTP of patients, in contrast to rrCBV, are distributed in narrow ranges minimally overlapped with control data. The rMTT and TTP could be more reliable parameters than rrCBV in assessing the hemodynamic disturbance in carotid occlusive disease

  8. Analysis of regional cerebral blood flow and distribution volume in Machado-Joseph disease by iodine-123I IMP single photon emission computed tomography

    International Nuclear Information System (INIS)

    Machado-Joseph disease (MJD) is an autosomal dominant spinocerebellar ataxia. Its clinical features vary greatly in different generations of the same family. Regional cerebral blood flow (rCBF) and distribution volume (Vd) in the pons, cerebellum, and cerebral cortex were measured in 12 patients with MJD by autoradiography (ARG) and the table look-up (TLU) method of iodine-123 IMP (123I-IMP) single photon emission computed tomography (SPECT). Representative cases were as follows: A 46-year-old woman first experienced gait ataxia at age 38. Computed tomography (CT) and magnetic resonance imaging (MRI) showed no atrophy in the pons or cerebellum, but rCBF measured by the 123I-IMP SPECT ARG method detected hypoperfusion in the pons, and cerebellar vermis and hemisphere. A 76-year-old woman first experienced gait ataxia at age 69. CT and MRI findings showed severe atrophy in the pons, and cerebellar vermis and hemisphere. Moreover, rCBF was decreased in the pons, whereas it was not decreased in the cerebellar vermis and hemisphere. In the pons of patients with MJD, rCBF was markedly decreased regardless of disease severity. Because this SPECT finding for the pons looked like a 'dot', we have called it the 'pontine dot sign'. In the MJD group, rCBF was significantly decreased in the pons (Student's t test, pd was also significantly decreased in the pons (pd for the pons and age at onset (r=0.59, pd in the cerebellar hemispheres and International Cooperative Ataxia Rating Scale (r=0.644, pd obtained by 123I-IMP SPECT for patients with MJD identified by gene analysis. Our study shows that SPECT measurement of rCBF and Vd is useful for understanding the pathophysiology of MJD. (author)

  9. EFFECTS OF LOW-INTENSITY CYCLE TRAINING WITH RESTRICTED LEG BLOOD FLOW ON THIGH MUSCLE VOLUME AND VO2MAX IN YOUNG MEN

    Directory of Open Access Journals (Sweden)

    Takashi Abe

    2010-09-01

    Full Text Available Concurrent improvements in aerobic capacity and muscle hypertrophy in response to a single mode of training have not been reported. We examined the effects of low-intensity cycle exercise training with and without blood flow restriction (BFR on muscle size and maximum oxygen uptake (VO2max. A group of 19 young men (mean age ± SD: 23.0 ± 1.7 years were allocated randomly into either a BFR-training group (n=9, BFR-training or a non-BFR control training group (n=10, CON-training, both of which trained 3 days/wk for 8 wk. Training intensity and duration were 40% of VO2max and 15 min for the BFR-training group and 40% of VO2max and 45 min for the CON-training group. MRI-measured thigh and quadriceps muscle cross-sectional area and muscle volume increased by 3.4-5.1% (P < 0.01 and isometric knee extension strength tended to increase by 7.7% (p < 0.10 in the BFR-training group. There was no change in muscle size (~0.6% and strength (~1.4% in the CON-training group. Significant improvements in VO2max (6.4% and exercise time until exhaustion (15.4% were observed in the BFR-training group (p < 0.05 but not in the CON-training group (-0.1 and 3. 9%, respectively. The results suggest that low-intensity, short-duration cycling exercise combined with BFR improves both muscle hypertrophy and aerobic capacity concurrently in young men.

  10. The feasibility and clinical application of flat-panel detector computer tomography in evaluating cerebral blood volume: an initial prospective study

    International Nuclear Information System (INIS)

    Objective: To investigate the feasibility and clinical value of the determination of cerebral blood volume (CBV) map by using flat-panel detector computer tomography (FDCT) angiography system. Methods: A prospective self-control clinical trial was conducted in 20 patients with cerebral ischemia who were encountered during the period from June 2010 to March 2011. All the patients were diagnosed as cerebral ischemic diseases and were scheduled to take interventional procedures. All patients underwent cerebral perfusion computer tomography (PCT) and CBV map exam which was performed by flat-panel detector computer tomography (FDCT-CBV). The CBV values obtained by the two exam types were analyzed and compared with each other by using statistic methods. Results: All PCT and FDCT-CBV exams were successfully accomplished in all the twenty patients. A significant correlation existed between the CBV images and CBV values obtained by the two exam types. The correlation coefficient was 0.68 (P<0.01). The Bland-Altman analysis showed a mean difference of -0.25±2.79 between FDCT-CBV and PCT-CBV, indicating that FDCT-CBV values were only slightly lower than those of PCT-CBV. Conclusion: CBV exam by using flat-panel detector angiography system is clinically feasible and the results of FDCT-CBV is comparable to those of PCT-CBV. As the FDCT-CBV can offer functional images of the whole brain within the catheter lab, this technique is very helpful in making the reasonable operation plan and in improving the safety of endovascular procedures in neurosurgery. (authors)

  11. Magnetization of concentrated polydisperse ferrofluids: Cluster expansion

    OpenAIRE

    Huke, B.; Luecke, M.

    2006-01-01

    The equilibrium magnetization of concentrated ferrofluids described by a system of polydisperse dipolar hard spheres is calculated as a function of the internal magnetic field using the Born--Mayer or cluster expansion technique. This paper extends the results of Phys. Rev. E 62, 6875 (2000) obtained for monodisperse ferrofluids. The magnetization is given as a power series expansion in two parameters related to the volume fraction and the coupling strength of the dipolar interaction, respect...

  12. Blood Clots

    Science.gov (United States)

    ... Index A-Z Blood Clots Blood clots are semi-solid masses of blood that can be stationary (thrombosis) ... treated? What are blood clots? Blood clots are semi-solid masses of blood. Normally, blood flows freely through ...

  13. Haemodynamic effects of plasma-expansion with hyperoncotic albumin in cirrhotic patients with renal failure: a prospective interventional study

    Directory of Open Access Journals (Sweden)

    Huber Wolfgang

    2008-08-01

    Full Text Available Abstract Background Patients with advanced cirrhosis of the liver typically display circulatory disturbance. Haemodynamic management may be critical for avoiding and treating functional renal failure in such patients. This study investigated the effects of plasma expansion with hyperoncotic albumin solution and the role of static haemodynamic parameters in predicting volume responsiveness in patients with advanced cirrhosis. Methods Patients with advanced cirrhosis (Child B and C of the liver receiving albumin substitution because of renal compromise were studied using trans-pulmonary thermodilution. Paired measurements before and after two infusions of 200 ml of 20% albumin per patient were recorded and standard haemodynamic parameters such as central venous pressure (CVP, mean arterial pressure (MAP, systemic vascular resistance index (SVRI, cardiac index (CI and derived variables were assessed, including global end-diastolic blood volume index (GEDVI, a parameter that reflects central blood volume Results 100 measurements in 50 patients (33 m/17 w; age 56 years (± 8; Child-Pugh-score 12 (± 2, serum creatinine 256 μmol (± 150 were analyzed. Baseline values suggested decreased central blood volumes GEDVI = 675 ml/m2 (± 138 despite CVP within the normal range (11 mmHg (± 5. After infusion, GEDVI, CI and CVP increased (682 ml/m2 (± 128 vs. 744 ml/m2 (± 171, p 2 (± 1.1 vs. 4.7 L/min/m2 (± 1.1, p 5/m2 (± 1144 vs. 1490 dyn s/cm5/m2 (± 837; p 2 = 0.51; p Conclusion In a substantial proportion of patients with advanced cirrhosis, plasma expansion results in an increase in central blood volume. GEDVI but not CVP behaves as an indicator of cardiac preload, whereas high baseline SVRI is predictive of fluid responsiveness.

  14. Vascular refilling is independent of volume overload in hemodialysis with moderate ultrafiltration requirements.

    Science.gov (United States)

    Kron, Susanne; Schneditz, Daniel; Leimbach, Til; Aign, Sabine; Kron, Joachim

    2016-07-01

    Introduction Blood volume changes and vascular refilling during hemodialysis (HD) and ultrafiltration (UF) have been assumed to depend on volume overload (Vo ). It was the aim to study the magnitude of vascular refilling in stable HD patients with moderate volume expansion in everyday dialysis using novel technical approaches. Methods Patients were studied during routine dialysis and UF based on clinical dry weight assessment. Pre-dialysis Vo was independently measured by bioimpedance spectroscopy. Vascular refilling volume (Vref ) was calculated as: Vref  = Vuf  - ΔV, where ΔV is the absolute blood volume change determined by on-line dialysate dilution using a commercial on-line hemodiafiltration machine incorporating a relative blood volume monitor, and where Vuf is the prescribed UF volume. Findings Thirty patients (dry weight: 81.0 ± 17.8 kg) were studied. Pre-dialysis Vo was 2.46 ± 1.45 L. Vuf was 2.27 ± 0.71 L, specific UF rate was 6.45 ± 2.43 mL/kg/h, and since ΔV was 0.66 ± 0.31 L, Vref was determined as 1.61 ± 0.58 L, corresponding to a constant refilling fraction (Fref ) of 70.6 ± 10.6%. Vref strongly correlated with Vuf (r(2)  = 0.82) but was independent of Vo and other volumes. Fref was also independent of Vo and other volumes normalized for various measures of body size. Discussion While vascular refilling and Fref is independent of Vo in treatments with moderate UF requirements, intravascular volume depletion increases with increasing UF requirements. The relationship between blood volume and Vo needs to be more closely examined in further studies to optimize volume control in everyday dialysis. PMID:27061224

  15. Analysis of regional cerebral blood flow and distribution volume in Machado-Joseph disease by iodine-{sup 123}I IMP single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Tsunemi; Nakajima, Takashi; Fukuhara, Nobuyoshi [National Saigata Hospital, Ohagata, Niigata (Japan)

    2001-09-01

    Machado-Joseph disease (MJD) is an autosomal dominant spinocerebellar ataxia. Its clinical features vary greatly in different generations of the same family. Regional cerebral blood flow (rCBF) and distribution volume (V{sub d}) in the pons, cerebellum, and cerebral cortex were measured in 12 patients with MJD by autoradiography (ARG) and the table look-up (TLU) method of iodine-123 IMP ({sup 123}I-IMP) single photon emission computed tomography (SPECT). Representative cases were as follows: A 46-year-old woman first experienced gait ataxia at age 38. Computed tomography (CT) and magnetic resonance imaging (MRI) showed no atrophy in the pons or cerebellum, but rCBF measured by the {sup 123}I-IMP SPECT ARG method detected hypoperfusion in the pons, and cerebellar vermis and hemisphere. A 76-year-old woman first experienced gait ataxia at age 69. CT and MRI findings showed severe atrophy in the pons, and cerebellar vermis and hemisphere. Moreover, rCBF was decreased in the pons, whereas it was not decreased in the cerebellar vermis and hemisphere. In the pons of patients with MJD, rCBF was markedly decreased regardless of disease severity. Because this SPECT finding for the pons looked like a 'dot', we have called it the 'pontine dot sign'. In the MJD group, rCBF was significantly decreased in the pons (Student's t test, p<0.01) and cerebellar vermis (p<0.05). The V{sub d} was also significantly decreased in the pons (p<0.005) in comparison with that for normal subjects. Pearson's correlation analysis yielded a significant relationship between the rCBF in the pons and age at onset (r=0.578, p<0.05). There was a strong correlation between the V{sub d} for the pons and age at onset (r=0.59, p<0.05). Person's correlation analysis also showed a significant relationship between the V{sub d} in the cerebellar hemispheres and International Cooperative Ataxia Rating Scale (r=0.644, p<0.05). The pontine rCBFs in patients with early onset MJD

  16. Regression equation for describing gluten thermal expansion

    Directory of Open Access Journals (Sweden)

    J. Grodek

    2007-12-01

    Full Text Available Testing of gluten ability of thermal expansion consisted in heating a small sample of freshly washed out gluten at temperatures causing the boiling of water within it. Gluten membranes extend around forming bubbles of water vapour under increase of pressure and are simultaneously being modified thermally. At certain volume of the bubbles, the membranes achieve maximum extensibility and further increasing of water vapour pressure causes their perforation. The dynamics of the expansion process was recorded by use of a digital camera. The proposed regression equation describes the dependence of the volume increment of gluten on heating time and allows to split the thermal expansion process into hyperbolic and linear components. The hyperbolic one is determined by a three-parameter function of hyperbolic tangent. The parameters a, c and b characterize the half of extent and duration of the hyperbolic expansion and its rate, respectively. The linear component can be meant as viscous flow of gluten, therefore it is determined by a one-parameter linear function. The parameter d means the rate of linear expansion. The volume increase of strong gluten at lowest temperature (110°C was very slow and its character was only linear (d. Higher heating temperatures (above 140°C caused considerably larger and faster hyperbolic expansion (a and b of strong gluten than of the weak one. However, the weak gluten in whole range of used temperatures was distinguished by almost twice faster linear expansion (d. It may suggest the existence of significant differences between wheat cultivars in terms of extensibility of thermally modified gluten membranes.

  17. Influence of genetic variance on sodium sensitivity of blood pressure.

    Science.gov (United States)

    Luft, F C; Miller, J Z; Weinberger, M H; Grim, C E; Daugherty, S A; Christian, J C

    1987-02-01

    To examine the effect of genetic variance on blood pressure, sodium homeostasis, and its regulatory determinants, we studied 37 pairs of monozygotic twins and 18 pairs of dizygotic twins under conditions of volume expansion and contraction. We found that, in addition to blood pressure and body size, sodium excretion in response to provocative maneuvers, glomerular filtration rate, the renin-angiotensin system, and the sympathetic nervous system are influenced by genetic variance. To elucidate the interaction of genetic factors and an environmental influence, namely, salt intake, we restricted dietary sodium in 44 families of twin children. In addition to a modest decrease in blood pressure, we found heterogeneous responses in blood pressure indicative of sodium sensitivity and resistance which were normally distributed. Strong parent-offspring resemblances were found in baseline blood pressures which persisted when adjustments were made for age and weight. Further, mother-offspring resemblances were observed in the change in blood pressure with sodium restriction. We conclude that the control of sodium homeostasis is heritable and that the change in blood pressure with sodium restriction is familial as well. These data speak to the interaction between the genetic susceptibility to hypertension and environmental influences which may result in its expression. PMID:3553721

  18. Model 1: Blood

    International Nuclear Information System (INIS)

    Because most radiopharmaceuticals are introduced into the body via the vascular system and may remain in the circulation for prolonged periods of time, it is useful to have a model of the blood as an aid in the estimation of radiation dose. It is extremely difficult to devise a precise blood model; the geometry is complex and distribution of blood may vary with position, physiological state and disease process. Estimates of blood volume distribution vary among investigators. Furthermore, the regional hematocrit varies throughout the body, thus affecting distribution of the labeled material according to whether it is attached to cellular elements or in the plasma. The size of the blood pool volumes range from the heart to the capillaries. Variable amounts of non-penetrating radiation contributions to organs depend on the volume of blood in the various sized vessels and the energy of the electrons which may penetrate into tissue from the blood vessel. The present model represents an advance in that it takes into account to some extent the distribution of significant blood pools in the body. Further refinement of the macro-geometry is possible with data which can now be obtained from modern radionuclide imaging equipment. A more difficult problem is definging the micro-geometry relative to the distribution of blood in capillaries and sinusoids, and their relationship to one another

  19. Expansion for Universal Quantifiers

    CERN Document Server

    Lenglet, Sergueï

    2012-01-01

    Expansion is an operation on typings (i.e., pairs of typing environments and result types) defined originally in type systems for the lambda-calculus with intersection types in order to obtain principal (i.e., most informative, strongest) typings. In a type inference scenario, expansion allows postponing choices for whether and how to use non-syntax-driven typing rules (e.g., intersection introduction) until enough information has been gathered to make the right decision. Furthermore, these choices can be equivalent to inserting uses of such typing rules at deeply nested positions in a typing derivation, without needing to actually inspect or modify (or even have) the typing derivation. Expansion has in recent years become simpler due to the use of expansion variables (e.g., in System E). This paper extends expansion and expansion variables to systems with forall-quantifiers. We present System Fs, an extension of System F with expansion, and prove its main properties. This system turns type inference into a c...

  20. Quantitative assessment of P-glycoprotein function in the rat blood-brain barrier by distribution volume of [C-11]verapamil measured with PET

    NARCIS (Netherlands)

    Bart, J; Willemsen, ATM; Groen, HJM; van der Graaf, WTA; Wegman, TD; Vaalburg, W; de Vries, EGE; Hendrikse, NH

    2003-01-01

    The blood-brain barrier (BBB) is a functional barrier that hampers the delivery of various drugs to the brain by its physicoanatomical properties and by the presence of ATP-driven drug efflux pumps, such as P-glycoprotein (P-gp). The aims of this study were (1) to study whether the distribution volu

  1. Age-Related Differences in Memory and Executive Functions in Healthy "APOE"[epsilon]4 Carriers: The Contribution of Individual Differences in Prefrontal Volumes and Systolic Blood Pressure

    Science.gov (United States)

    Bender, Andrew R.; Raz, Naftali

    2012-01-01

    Advanced age and vascular risk are associated with declines in the volumes of multiple brain regions, especially the prefrontal cortex, and the hippocampus. Older adults, even unencumbered by declining health, perform less well than their younger counterparts in multiple cognitive domains, such as episodic memory, executive functions, and speed of…

  2. Right ventricular volume determination by continuous [sup 81m]Kr infusion and [sup 99m]Tc blood pool imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Shinichiro; Yamashita, Saburo; Suzuki, Tetsuo; Muramatsu, Toshihiro; Ide, Masao; Suzuki, Shigeo; Dohi, Yutaka; Nishimura, Katsuyuki; Miyamae, Tatsuya (Saitama Medical School, Moroyama (Japan))

    1992-10-01

    Our newly developed radionuclide method for the calculation of right ventricular (RV) volume was examined. Using a semi-geometric count-based method, volume can be measured by the following equation: Cv=Cm/(L/d). V=(Ct/Cv)xd[sup 3]=(Ct/Cm)xLxd[sup 2]. (V=volume, Cv=voxel count, Cm=the maximum count of a container, Ct=the total count of the container, L=maximum length of the image of the container, L=maximum length of the image of the container obtained from a direction perpendicular to the direction where the count data were collected, and d=pixel size). A phantom study was performed by setting a cylindrical container in a system which circulated 5 liters of water per minute. [sup 81m]Kr solution was infused continuously into the container, and images of the container were collected for one minute. Cm and Ct were obtained, and because the container was cylindrical, the maximum width of the image of the container was measured as L. The volume of the container was calculated using the above equation. This theorem was applied to RV images obtained in the 30 degree right anterior oblique position by continuous infusion of the [sup 81m]Kr solution. Multiple gated acquisition was performed and RV end-diastolic maximum counts and total counts were obtained. The RV maximum width was measured as L on the end-diastolic cardiac pool image with [sup 99m]Tc-D-HSA collected in the 40 degree left anterior oblique position. The values obtained from these two images were substituted in the above equation and the RV end-diastolic volume (RV-EDV) was calculated. The RV ejection fraction (RV-EF) was obtained from the [sup 81m]Kr image. The RV stroke volume (SV) was calculated from multiplying the RV-EDV by the RV-EF. This value was compared to the SV with thermodilution. The correlation of these two values was r=0.90. This new method for calculating RV volume was thus considered useful. (author).

  3. Multipole expansions in magnetostatics

    International Nuclear Information System (INIS)

    Multipole expansions of the magnetic field of a spatially restricted system of stationary currents and those for the potential function of such currents in an external magnetic field are studied using angular momentum algebraic techniques. It is found that the expansion for the magnetic induction vector is made identical to that for the electric field strength of a neutral system of charges by substituting electric for magnetic multipole moments. The toroidal part of the multipole expansion for the magnetic field vector potential can, due to its potential nature, be omitted in the static case. Also, the potential function of a system of currents in an external magnetic field and the potential energy of a neutral system of charges in an external electric field have identical multipole expansions. For axisymmetric systems, the expressions for the field and those for the potential energy of electric and magnetic multipoles are reduced to simple forms, with symmetry axis orientation dependence separated out. (methodological notes)

  4. Multipole expansions in magnetostatics

    Energy Technology Data Exchange (ETDEWEB)

    Agre, Mark Ya [National University of ' Kyiv-Mohyla Academy' , Kyiv (Ukraine)

    2011-02-28

    Multipole expansions of the magnetic field of a spatially restricted system of stationary currents and those for the potential function of such currents in an external magnetic field are studied using angular momentum algebraic techniques. It is found that the expansion for the magnetic induction vector is made identical to that for the electric field strength of a neutral system of charges by substituting electric for magnetic multipole moments. The toroidal part of the multipole expansion for the magnetic field vector potential can, due to its potential nature, be omitted in the static case. Also, the potential function of a system of currents in an external magnetic field and the potential energy of a neutral system of charges in an external electric field have identical multipole expansions. For axisymmetric systems, the expressions for the field and those for the potential energy of electric and magnetic multipoles are reduced to simple forms, with symmetry axis orientation dependence separated out. (methodological notes)

  5. Weakly relativistic plasma expansion

    Energy Technology Data Exchange (ETDEWEB)

    Fermous, Rachid, E-mail: rfermous@usthb.dz; Djebli, Mourad, E-mail: mdjebli@usthb.dz [Theoretical Physics Laboratory, Faculty of Physics, USTHB, B.P. 32 Bab-Ezzouar, 16079 Algiers (Algeria)

    2015-04-15

    Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamical multi-fluid equations, we investigated the expansion of both dense and under-dense plasmas. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. Numerical investigations have shown that relativistic effects are important for under-dense plasma and are characterized by a finite ion front velocity. Dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.

  6. Grey matter blood flow and volume are reduced in association with white matter hyperintensity lesion burden: a cross-sectional MRI study

    OpenAIRE

    David Ellis Crane; Black, Sandra E.; Mikulis, David J; Nestor, Sean M.; Donahue, Manus J; MacIntosh, Bradley J.

    2015-01-01

    Cerebral White Matter Hyperintensities (WMH) are associated with vascular risk factors and age-related cognitive decline. WMH have primarily been associated with global white matter and grey matter (GM) changes and less is known about regional effects in GM. The purpose of this study was to test for an association between WMH and two GM imaging measures: cerebral blood flow (CBF) and voxel-based morphometry. Twenty-six elderly adults with mild to severe WMH participated in this cross-secti...

  7. Systematic survey of the design, statistical analysis, and reporting of studies published in the 2008 volume of the Journal of Cerebral Blood Flow and Metabolism

    OpenAIRE

    Vesterinen, Hanna V; Egan, Kieren; Deister, Amelie; Schlattmann, Peter; Macleod, Malcolm R.; Dirnagl, Ulrich

    2010-01-01

    Translating experimental findings into clinically effective therapies is one of the major bottlenecks of modern medicine. As this has been particularly true for cerebrovascular research, attention has turned to the quality and validity of experimental cerebrovascular studies. We set out to assess the study design, statistical analyses, and reporting of cerebrovascular research. We assessed all original articles published in the Journal of Cerebral Blood Flow and Metabolism during the year 200...

  8. Quantitation of regional cerebral blood flow corrected for partial volume effect using O-15 water and PET: I. Theory, error analysis, and stereologic comparison

    DEFF Research Database (Denmark)

    Lida, H; Law, I; Pakkenberg, B;

    2000-01-01

    the white matter fraction with fixed white matter CBF as the most reliable and suitable for estimating the gray matter CBF. Reproducibility with this model was 11% for estimating the gray matter CBF. The volume of gray matter tissue can also be estimated using this model and was significantly...... formulated four mathematical models that describe the dynamic behavior of a freely diffusible tracer (H215O) in a region of interest (ROI) incorporating estimates of regional tissue flow that are independent of PVE. The current study was intended to evaluate the feasibility of these models and to establish a...... onto the PET images in which regional CBF values and the water perfusable tissue fraction for the cortical gray matter tissue (hence the volume of gray matter) were estimated. After the PET study, the animals were killed and stereologic analysis was performed to assess the gray matter mass in the...

  9. Clinical application of a right ventricular pressure-volume loop determined by gated blood-pool imaging and simultaneously measured right ventricular pressure

    International Nuclear Information System (INIS)

    The data obtained by ECG-gated radionuclide angiography were collected simultaneously with right ventricular pressure and thermal cardiac output (CO) obtained by a Swan-Ganz catheter in Scintipac 1200 (Shimazu Co) in order to create a right ventricular pressure-volume (RV P-V) loop. Subjects consisted of 15 patients with old myocardial infarction (MI group), seven with angina pectoris (AP group), six with congestive cardiomyopathy (CCM group) and five with neurocirculatory asthenia (NCA group). Right ventricular end-diastolic volume (RVEDV) was calculated as RVEDV = CO/(EF x HR) (CO = cardiac output; HR = heart rate). Systolic work (W sub(S)), diastolic work (W sub(D)) and net work (W sub(N)) were calculated from a RV P-V loop by Simpson's method. The measurements were performed before and 5 min after sublingual administration of nitroglycerin (NG) (0.3 mg). The results were as follows: 1. RV P-V loops shifted towards the left lower part of the P-V plane after sublingual administration of nitroglycerin, indicating the reduction of pressure and volume of the right ventricle. 2. Right ventricular ejection fraction (RVEF) in the MI, AP and CCM groups showed smaller values than that of the NCA group. 3. Right ventricular end-diastolic volume index (RVEDVI) showed a converse relation with RVEF. 4. Cardiac index in all groups decreased after NG and a statistical significance was seen in the MI, AP and NCA groups (p<0.05). 5. RV W sub(S), RV W sub(D) and RV W sub(N) showed no difference among each groups in the control state, and significantly decreased after NG. We conclude that the present method using RV P-V loop might be useful as a noninvasive bedside monitoring and permits the evaluation of RV function in a clinical setting

  10. Clinical application of a right ventricular pressure-volume loop determined by gated blood-pool imaging and simultaneously measured right ventricular pressure

    Energy Technology Data Exchange (ETDEWEB)

    Yasue, Takao; Watanabe, Sachiro; Sugishita, Nobuyoshi; Tanaka, Tsutomu; Yokoyama, Hideo (Prefectural Gifu Hospital (Japan))

    1983-09-01

    The data obtained by ECG-gated radionuclide angiography were collected simultaneously with right ventricular pressure and thermal cardiac output (CO) obtained by a Swan-Ganz catheter in Scintipac 1200 (Shimazu Co) in order to create a right ventricular pressure-volume (RV P-V) loop. Subjects consisted of 15 patients with old myocardial infarction (MI group), seven with angina pectoris (AP group), six with congestive cardiomyopathy (CCM group) and five with neurocirculatory asthenia (NCA group). Right ventricular end-diastolic volume (RVEDV) was calculated as RVEDV = CO/(EF x HR) (CO = cardiac output; HR = heart rate). Systolic work (W sub(S)), diastolic work (W sub(D)) and net work (W sub(N)) were calculated from a RV P-V loop by Simpson's method. The measurements were performed before and 5 min after sublingual administration of nitroglycerin (NG) (0.3 mg). The results were as follows: 1. RV P-V loops shifted towards the left lower part of the P-V plane after sublingual administration of nitroglycerin, indicating the reduction of pressure and volume of the right ventricle. 2. Right ventricular ejection fraction (RVEF) in the MI, AP and CCM groups showed smaller values than that of the NCA group. 3. Right ventricular end-diastolic volume index (RVEDVI) showed a converse relation with RVEF. 4. Cardiac index in all groups decreased after NG and a statistical significance was seen in the MI, AP and NCA groups (p<0.05). 5. RV W sub(S), RV W sub(D) and RV W sub(N) showed no difference among each groups in the control state, and significantly decreased after NG. We conclude that the present method using RV P-V loop might be useful as a noninvasive bedside monitoring and permits the evaluation of RV function in a clinical setting.

  11. Gyrification from constrained cortical expansion

    CERN Document Server

    Tallinen, Tuomas; Biggins, John S; Mahadevan, L

    2015-01-01

    The exterior of the mammalian brain - the cerebral cortex - has a conserved layered structure whose thickness varies little across species. However, selection pressures over evolutionary time scales have led to cortices that have a large surface area to volume ratio in some organisms, with the result that the brain is strongly convoluted into sulci and gyri. Here we show that the gyrification can arise as a nonlinear consequence of a simple mechanical instability driven by tangential expansion of the gray matter constrained by the white matter. A physical mimic of the process using a layered swelling gel captures the essence of the mechanism, and numerical simulations of the brain treated as a soft solid lead to the formation of cusped sulci and smooth gyri similar to those in the brain. The resulting gyrification patterns are a function of relative cortical expansion and relative thickness (compared with brain size), and are consistent with observations of a wide range of brains, ranging from smooth to highl...

  12. Resonant state expansions

    International Nuclear Information System (INIS)

    The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.)

  13. Blood pressure

    Science.gov (United States)

    ... the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart contracts, which ... as it relaxes, which is called diastole. Normal blood pressure is considered to be a systolic blood pressure ...

  14. Blood transfusions

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000431.htm Blood transfusions To use the sharing features on this ... several sources of blood which are described below. Blood From the Public (Volunteer Blood Donation) The most ...

  15. Blood Basics

    Science.gov (United States)

    ... Patient Group Links Advocacy Toolkit Home For Patients Blood Basics Blood is a specialized body fluid. It ... about 9 pints. Jump To: The Components of Blood and Their Importance Many people have undergone blood ...

  16. Blood Thinners

    Science.gov (United States)

    If you have some kinds of heart or blood vessel disease, or if you have poor blood flow to your brain, your doctor may recommend that you take a blood thinner. Blood thinners reduce the risk of heart ...

  17. Blood culture

    Science.gov (United States)

    Culture - blood ... A blood sample is needed . The site where blood will be drawn is first cleaned with an antiseptic such ... organism from the skin getting into (contaminating) the blood sample and causing a false-positive result (see ...

  18. Gray matter blood flow and volume are reduced in association with white matter hyperintensity lesion burden: a cross-sectional MRI study

    OpenAIRE

    Crane, David E.; Black, Sandra E.; Ganda, Anoop; Mikulis, David J; Nestor, Sean M.; Donahue, Manus J; MacIntosh, Bradley J.

    2015-01-01

    Cerebral White Matter Hyperintensities (WMH) are associated with vascular risk factors and age-related cognitive decline. WMH have primarily been associated with global white matter and gray matter (GM) changes and less is known about regional effects in GM. The purpose of this study was to test for an association between WMH and two GM imaging measures: cerebral blood flow (CBF) and voxel-based morphometry (VBM). Twenty-six elderly adults with mild to severe WMH participated in this cross-se...

  19. Rapid quantification of conjugated and unconjugated bile acids and C27 precursors in dried blood spots and small volumes of serum[S

    OpenAIRE

    Janzen, N; Sander, S.; Terhardt, M.; Das, A.M; Sass, J.O.; Kraetzner, R.; Rosewich, H.; Peter, M.; Sander, J.

    2010-01-01

    The aim of the study was to develop a method for fast and reliable diagnosis of peroxisomal diseases and to facilitate differential diagnosis of cholestatic hepatopathy. For the quantification of bile acids and their conjugates as well as C27 precursors di- and trihydroxycholestanoic acid (DHCA, THCA), in small pediatric blood samples we combined HPLC separation on a reverse-phase C18 column with ESI-MS/MS analysis in the negative ion mode. Analysis was done with good precision (CV 3,7%–11.1%...

  20. Expansion joints for LMFBR

    International Nuclear Information System (INIS)

    This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of the development reviewed. Large Na (sodium)-heat transfer systems require a lot of valuable space if the component lay-out does not include compensation devices. So, in order to condense the spatial requirement as much as possible, expansion joints must be integrated into the pipe system. There are two basic types to suit the purpose: axial expansion joints and angular expansion joints. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows. Expansion joints must be designed and mounted in a manner to completely withstand seismic forces. The design must exclude any damage to the bellows during intermittent operations, that is, when sodium is drained the bellows' folds must be completely empty; otherwise residual solidified sodium could destroy the bellows when restarting. The expansion joints must be engineered on the basis of the following design data for the secondary system of the SNR project: working pressure: 16 bar; failure mode pressure: 5 events; failure mode: 5 sec., 28.5 bar, 520 deg. C; working temperature: 520 deg. C; temperature transients: 30 deg. C/sec.; service life: 200,000 h; number of load cycles: 104; material: 1.4948 or 1.4919; layer thickness of folds: 0.5 mm; angular deflection (DN 800): +3 deg. C or; axial expansion absorption (DN 600): ±80 mm; calculation: ASME class. The bellows' development work is not handled within this scope. The bellows are supplied by leading manufacturers, and warrant highest quality. Multiple bellows were selected on the basis of maximum elasticity - a property

  1. Targeted expansion and regulation of genetically modified cord blood stem/progenitor cells in vitro%靶基因调控的脐血干/祖细胞体外长期扩增与调控

    Institute of Scientific and Technical Information of China (English)

    赵声明; 彭明婷; 顾惜春; 常乃柏

    2008-01-01

    BACKGROUND: Cord blood stem cells are one of ideal target cells for gene therapy, but low gene transferring rate is the main difficulty at recent. Janus kinase tyrosine 2 (JAK2) plays an important role in self-renewing of cord blood stem/progenitor cell12s. Therefore, cord blood CD34+ cell line modified by target-amplified JAK2 genes has been developed yet by using gene regulating expression technique in order to overcome low transferring rate of cord blood genes.OBJECTIVE: To investigate the feasibility and reliability of a long-term amplified regulation for cord blood stem/progenitor cells mediated by transgene JAK2. SETTING: Department of Hematology, Beijing Hospital, Ministry of Health.MATERIALS: The experiment was carried out in the Laboratory of Hematological Department, Beijing Hospital, Ministry of Health from June 2003 to April 2006. Cord blood was derived from umbilical cord which was immediately cut from healthy, full-term and natural-parturition infants and was provided by Department of Obstetrics & Gynecology, Beijing Hospital. The experiment was approved by the local ethical committee, and informed consent was obtained from expectant mothers and their relatives for the use of cord blood cells. MiniMACS magnetic separation apparatus and immunomagnetic beads adsorbing CD34 single antibody were provided by Miltenyi Biotec Company, Germany; flow cytometer by FACScalibur, USA; recombinant human stem cell factor (rhSCF), Flt3 ligand (FL), human interleukin-6 (hIL-6), granulocyte macrophage colony stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF) and thrombopoeitin (TPO) by PeproTec Company; nude mice of the SPF level by Animal Center of Beijing Medical University.METHODS: Retroviral vector MGI-F2JAK2, which was composed of functional catalytic domain of JAK2 genes and two site proteins (2xF36v, F2) combined with synthetic drug (AP20187) of target gene of small molecules, was constructed. AP20187 might specially combine with F36v to

  2. Principles of Thermal Expansion in Feldspars

    Science.gov (United States)

    Hovis, Guy; Medford, Aaron; Conlon, Maricate; Tether, Allison; Romanoski, Anthony

    2010-05-01

    Following the recent thermal expansion work of Hovis et al. (1) on AlSi3 feldspars, we have investigated the thermal expansion of plagioclase, Ba-K, and Ca-K feldspar crystalline solutions. X-ray powder diffraction data were collected between room temperature and 925 °C on six natural plagioclase specimens ranging in composition from anorthite to oligoclase, the K-exchanged equivalents of these plagioclase specimens, and five synthetic Ba-K feldspars with compositions ranging from 25 to 99 mol % BaAl2Si2O8. The resulting thermal expansion coefficients (α) for volume have been combined with earlier results for end-member Na- and K-feldspars (2,3). Unlike AlSi3 feldspars, Al2Si2 feldspars, including anorthite and celsian from the present study plus Sr- and Pb-feldspar from other workers (4,5), show essentially constant and very limited thermal expansion, regardless of divalent cation size. In the context of structures where the Lowenstein rule (6) requires Al and Si to alternate among tetrahedra, the proximity of bridging Al-O-Si oxygen ions to divalent neighbors (ranging from 0 to 2) produces short Ca-O (or Ba-O) bonds (7,8) that apparently are the result of local charge-balance requirements (9). Gibbs et al. (10) suggest that short bonds such as these have a partially covalent character. This in turn stiffens the structure. Thus, for feldspar series with coupled substitution the change away from a purely divalent M-site occupant gives the substituting (less strongly bonded) monovalent cations increasingly greater influence on thermal expansion. Overall, then, thermal expansion in the feldspar system is well represented on a plot of α against room-temperature volume, where one sees a quadrilateral bounded by data for (A) AlSi3 feldspars whose expansion behavior is controlled largely by the size of the monovalent alkali-site occupant, (B) Al2Si2 feldspars whose expansion is uniformly limited by partially-covalent bonds between divalent M-site occupants and

  3. Integrative Analysis of mRNA, microRNA, and Protein Correlates of Relative Cerebral Blood Volume Values in GBM Reveals the Role for Modulators of Angiogenesis and Tumor Proliferation

    Science.gov (United States)

    Rao, Arvind; Manyam, Ganiraju; Rao, Ganesh; Jain, Rajan

    2016-01-01

    Dynamic susceptibility contrast-enhanced magnetic resonance imaging is routinely used to provide hemodynamic assessment of brain tumors as a diagnostic as well as a prognostic tool. Recently, it was shown that the relative cerebral blood volume (rCBV), obtained from the contrast-enhancing as well as -nonenhancing portion of glioblastoma (GBM), is strongly associated with overall survival. In this study, we aim to characterize the genomic correlates (microRNA, messenger RNA, and protein) of this vascular parameter. This study aims to provide a comprehensive radiogenomic and radioproteomic characterization of the hemodynamic phenotype of GBM using publicly available imaging and genomic data from the Cancer Genome Atlas GBM cohort. Based on this analysis, we identified pathways associated with angiogenesis and tumor proliferation underlying this hemodynamic parameter in GBM. PMID:27053917

  4. Ultrasound attenuation dependence on air compression or expansion processes

    OpenAIRE

    Jakevicius, L.; Demcenko, A.; Mardosaite, R.

    2010-01-01

    In this work variation of ultrasonic attenuation coefficient is analyzed in terms of air compression or expansion processes. In closed spaces changing air volume, the ultrasound attenuation coefficient depends on thermodynamic processes which occur during the air volume change. Two limiting cases are possible: 1) if the change of air volume is very slow or intensive heat exchange occurs between the system and surrounding environments, so the system stays in a thermodynamic equilibrium; theref...

  5. Expansion of Pannes

    Science.gov (United States)

    For the Long Island, New Jersey, and southern New England region, one facet of marsh drowning as a result of accelerated sea level rise is the expansion of salt marsh ponds and pannes. Over the past century, marsh ponds and pannes have formed and expanded in areas of poor drainag...

  6. THESAURUS AND QUERY EXPANSION

    Directory of Open Access Journals (Sweden)

    Hazra Imran

    2009-11-01

    Full Text Available The explosive growth of the World Wide Web is making it difficult for a user to locate information that isrelevant to his/her interest. Though existing search engines work well to a certain extent but they still faceproblems like word mismatch which arises because the majority of information retrieval systemscompare query and document terms on lexical level rather than on semantic level and short query: theaverage length of queries by the user is less than two words. Short queries and the incompatibilitybetween the terms in user queries and documents strongly affect the retrieval of relevant document.Query expansion has long been suggested as a technique to increase the effectiveness of the informationretrieval. Query expansion is the process of supplementing additional terms or phrases to the originalquery to improve the retrieval performance. The central problem of query expansion is the selection ofthe expansion terms based on which user’s original query is expanded. Thesaurus helps to solve thisproblem. Thesaurus have frequently been incorporated in information retrieval system for identifying thesynonymous expressions and linguistic entities that are semantically similar. Thesaurus has been widelyused in many applications, including information retrieval and natural language processing.

  7. OPEC future capacity expansions

    International Nuclear Information System (INIS)

    This conference presentation examined OPEC future capacity expansions including highlights from 2000-2004 from the supply perspective and actions by OPEC; OPEC spare capacity in 2005/2006; medium-term capacity expansion and investments; long-term scenarios, challenges and opportunities; and upstream policies in member countries. Highlights from the supply perspective included worst than expected non-OPEC supply response; non-OPEC supply affected by a number of accidents and strikes; geopolitical tensions; and higher than expected demand for OPEC crude. OPEC's actions included closer relationship with other producers and consumers; capacity expansions in 2004 and 2005/2006; and OPEC kept the market well supplied with crude in 2004. The presentation also provided data using graphical charts on OPEC net capacity additions until 2005/2006; OPEC production versus spare capacity from 2003 to 2005; OPEC production and capacity to 2010; and change in required OPEC production from 2005-2020. Medium term expansion to 2010 includes over 60 projects. Medium-term risks such as project execution, financing, costs, demand, reserves, depletion, integration of Iraq, and geopolitical tensions were also discussed. The presentation concluded that in the long term, large uncertainties remain; the peak of world supply is not imminent; and continued and enhanced cooperation is essential to market stability. tabs., figs

  8. Bed expansion crucible tests

    International Nuclear Information System (INIS)

    The Am/Cm program will vitrify the americium and curium currently stored in F-canyon. A batch flowsheet has been developed (with non-radioactive surrogate feed in place of the F-canyon solution) and tested full-scale in the 5-inch Cylindrical Induction Melter (CIM) facility at TNX. During a normal process run, a small bed expansion occurs when oxygen released from reduction of cerium (IV) oxide to cerium (III) oxide is trapped in highly viscous glass. The bed expansion is characterized by a foamy layer of glass that slowly expands as the oxygen is trapped and then dissipates when the viscosity of the foam becomes low enough to allow the oxygen to escape. Severe bed expansions were noted in the 5-inch CIM when re-heating after an interlock during the calcination phase of the heat cycle, escaping the confines of the melter vessel. In order to better understand the cause of the larger than normal bed expansion and to develop mitigating techniques, a series of three crucible tests were conducted

  9. Electroencephalography reveals lower regional blood perfusion and atrophy of the temporoparietal network associated with memory deficits and hippocampal volume reduction in mild cognitive impairment due to Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Moretti DV

    2015-02-01

    Full Text Available Davide Vito MorettiNational Institute for the research and cure of Alzheimer’s disease, S. John of God, Fatebenefratelli, Brescia, Italy Background: An increased electroencephalographic (EEG upper/lower alpha power ratio has been associated with less regional blood perfusion, atrophy of the temporoparietal region of the brain, and reduction of hippocampal volume in subjects affected by mild cognitive impairment due to Alzheimer’s disease as compared with subjects who do not develop the disease. Moreover, EEG theta frequency activity is quite different in these groups. This study investigated the correlation between biomarkers and memory performance.Methods: EEG α3/α2 power ratio and cortical thickness were computed in 74 adult subjects with prodromal Alzheimer’s disease. Twenty of these subjects also underwent assessment of blood perfusion by single-photon emission computed tomography (SPECT. Pearson’s r was used to assess the correlation between cortical thinning, brain perfusion, and memory impairment.Results: In the higher α3/α2 frequency power ratio group, greater cortical atrophy and lower regional perfusion in the temporoparietal cortex was correlated with an increase in EEG theta frequency. Memory impairment was more pronounced in the magnetic resonance imaging group and SPECT groups.Conclusion: A high EEG upper/low alpha power ratio was associated with cortical thinning and less perfusion in the temporoparietal area. Moreover, atrophy and less regional perfusion were significantly correlated with memory impairment in subjects with prodromal Alzheimer’s disease. The EEG upper/lower alpha frequency power ratio could be useful for identifying individuals at risk for progression to Alzheimer’s dementia and may be of value in the clinical context.Keywords: electroencephalography, perfusion, atrophy, temporoparietal network, memory deficits, hippocampal volume, mild cognitive impairment, Alzheimer’s disease

  10. Simultaneous in vivo synchrotron radiation computed tomography of regional ventilation and blood volume in rabbit lung using combined K-edge and temporal subtraction

    Energy Technology Data Exchange (ETDEWEB)

    Suhonen, H [Department of Physical Sciences, University of Helsinki (Finland); Porra, L [Department of Physical Sciences, University of Helsinki (Finland); Bayat, S [Universite de Picardie Jules Verne, Faculte de Medecine, PERITOX (EA-INI RIS) and Cardiologie et Pneumo-Allerglogie Pediatriques, CHU Amiens (France); Sovijaervi, A R A [Department of Clinical Physiology and Nuclear Medicine, Helsinki University Central Hospital, Helsinki (Finland); Suortti, P [Department of Physical Sciences, University of Helsinki (Finland)

    2008-02-07

    In K-edge subtraction (KES) imaging with synchrotron radiation computed tomography (SRCT), two images are taken simultaneously using energies above and below the K-absorption edge of a contrast agent. A logarithmic difference image reveals the contrast agent concentration with good accuracy. Similarly, in temporal subtraction imaging (TSI) the reference image is taken before the introduction of the contrast agent. Quantitative comparisons of in vivo images of rabbit lung indicated that similar results for concentrations of iodine in blood vessels and xenon in airways are obtained by KES and TSI, but the level of noise and artifacts was higher in the latter. A linear fit showed that in the lung parenchyma {rho}{sub TSI} = (0.97 {+-} 0.03){rho}{sub KES} + (0.00 {+-} 0.05) for xenon and {rho}{sub TSI} = (1.21 {+-} 0.15){rho}{sub KES} + (0.0 {+-} 0.1) for iodine. For xenon the calculation of time constant of ventilation gave compatible values for both of the methods. The two methods are combined for the simultaneous determination of the xenon concentration (by KES) and the iodine concentration (by TSI) in lung imaging, which will allow simultaneous in vivo determination of ventilation and perfusion.

  11. The Hydration Characteristics and Expansion Machanism of Expansive Cement at Low W/B Ratio

    Institute of Scientific and Technical Information of China (English)

    LU Lin-nu; HE Yong-jia; LI Yue; DING Qing-jun; HU Shu-guang

    2003-01-01

    The hydration characteristics and expansion impetus of three kinds of cement paste under freeand confined-curing conditions were investigated, which were respectively mixed with three different kinds of expansive agent at low W/ B ratio. The results show that the hydration products of pure cement paste and paste mixed with expansive agent are same, but the amount of hydration products , un-hydrated C3 S and C2 S are obviously different at the same hydration age. At 3 d age, the amount of CH in pure cement paste is less than that of paste mixed with expaasive agent, but it is reverse when at 28d age. The amount of AFt at 3d and 28d age in pure cement paste is less than those of paste mixed with expansive agent. Regardless of under free- or confined-curing condition, the amount of ettringite produced varies little since 3 d age. The joint effect of the tumefaction of gel-ettringite due to water absorption and the expansive pressure on the pore caased by the crystalloid ettringite is the cause of the volume expansion of cement paste, and the former effect is much greater than the latter .

  12. Antihypertensive Treatment and Change in Blood Pressure Are Associated With the Progression of White Matter Lesion Volumes: The Three-City (3C)-Dijon Magnetic Resonance Imaging Study

    International Nuclear Information System (INIS)

    Background-Blood pressure (BP) is recognized as a major risk factor for white matter lesions (WMLs), but longitudinal data are scarce, and there is insufficient evidence for the benefit of antihypertensive therapy on WML progression. We studied the relationship between BP change and WML volume progression over time in a sample of 1319 elderly individuals who had 2 cerebral magnetic resonance imaging examinations 4 years apart. We also examined the impact of antihypertensive treatment on WML progression. Methods and Results-Subjects were participants from the Three-City (3C)-Dijon Magnetic Resonance Imaging Study, a prospective population-based cohort of elderly ≥65 years of age. WML volumes and their progression were estimated with the use of a fully automatic procedure. We performed ANCOVA models first to assess the association between BP change and WML progression and second to estimate the relation between antihypertensive treatment and WML load progression. Baseline and change in BP were significant predictors of higher WML progression over time after controlling for potential confounders. Among subjects with high SBP (160 mm Hg) at baseline not treated by antihypertensive medication, antihypertensive treatment started within 2 years was related to a smaller increase in WML volume at a 4-year follow-up (0.24 cm3; SE0.44 cm3) than no hypertensive treatment (1.60 cm3; SE0.26 cm3; P0.0008) on multivariable modeling. Conclusions-Our findings reinforce the hypothesis that hypertension is a strong predictor of WML and that adequate treatment may reduce the course of WML progression. Because WMLs are linked to both dementia and stroke risks, these results could have implications for future preventive trials. (authors)

  13. Blood Types

    Science.gov (United States)

    ... How Can I Help a Friend Who Cuts? Blood Types KidsHealth > For Teens > Blood Types Print A A ... or straight hair instead of curly. ...Make Eight Blood Types The different markers that can be found in ...

  14. Blood Types

    Science.gov (United States)

    ... confidence to respond in emergency situations with the skills that can help to save a life. Learn more » Red Cross Information Donating Blood Learn About Blood Hosting a Blood Drive For Hospitals Engage with Us About Us Media ...

  15. Financing electricity expansion

    International Nuclear Information System (INIS)

    Expansion of electricity supply is associated with economic development. The installation and enlargement of power systems in developing countries entails a huge financial burden, however. Energy consumers in such countries must pay not only for supplies but for the cost of raising the capital for expansion on the international markets. Estimates are presented for the capital expenditure for electricity supply over the period 1990 to 2020 for the major world regions, using approximations for the cost of plant and capital and for the returns earned. These data lead to the conclusion that the five regions with the lowest per capita incomes are those which will need the major part of the capital expenditure and the highest percentage of external finance. (6 tables) (UK)

  16. Operator product expansion algebra

    International Nuclear Information System (INIS)

    The Operator Product Expansion (OPE) is a theoretical tool for studying the short distance behaviour of products of local quantum fields. Over the past 40 years, the OPE has not only found widespread computational application in high-energy physics, but, on a more conceptual level, it also encodes fundamental information on algebraic structures underlying quantum field theories. I review new insights into the status and properties of the OPE within Euclidean perturbation theory, addressing in particular the topics of convergence and ''factorisation'' of the expansion. Further, I present a formula for the ''deformation'' of the OPE algebra caused by a quartic interaction. This formula can be used to set up a novel iterative scheme for the perturbative computation of OPE coefficients, based solely on the zeroth order coefficients (and renormalisation conditions) as initial input.

  17. Expansion at Olympic Dam

    International Nuclear Information System (INIS)

    The Olympic Dam orebody is the 6th largest copper and the single largest uranium orebody in the world. Mine production commenced in June 1988, at an annual production rate of around 45,000 tonnes of copper and 1,000 tonnes of uranium. Western Mining Corporation announced in 1996 a proposed $1.25 billion expansion of the Olympic Dam operation to raise the annual production capacity of the mine to 200,000 tonnes of copper, approximately 3,700 tonnes of uranium, 75,000 ounces of gold and 950,000 ounces of silver by 2001. Further optimisation work has identified a faster track expansion route, with an increase in the capital cost to $1.487 billion but improved investment outcome, a new target completion date of end 1999, and a new uranium output of 4,600 tonnes per annum from that date

  18. Expansion of Hanford concrete

    International Nuclear Information System (INIS)

    This report presents results of measurements of thermal expansion of concrete cores from Hanford, Washington facilities, and concrete cast at the Construction Technology Laboratories of Portland Cement Association (CTL/PCA). Thermal expansion was measured from room temperature to 16000F on 0.5 x 3.0-in. specimens heated at a rate of 100F/min. Specimens were cored from concrete cylinders cast at CTL/PCA in 1975 and 1977, and from cylindrical cores taken from the Purex Building and Waste Tank Farms at the Hanford, Washington complex. A total of 14 specimens were tested: eight tests on CTL/PCA cast concrete, two tests on material from the Purex Building, and four tests on Waste Tank Farms concrete. All tests were conducted using a commercially built dilatometer of high strain resolution

  19. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Bendtsen, F; Christensen, N J;

    1990-01-01

    To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate of...... albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

  20. IKEA's International Expansion

    OpenAIRE

    Harapiak, Clayton

    2013-01-01

    This case concerns a global retailing firm that is dealing with strategic management and marketing issues. Applying a scenario of international expansion, this case provides a thorough analysis of the current business environment for IKEA. Utilizing a variety of methods (e.g. SWOT, PESTLE, McKinsey Matrix) the overall objective is to provide students with the opportunity to apply their research skills and knowledge regarding a highly competitive industry to develop strategic marketing strateg...

  1. China petrochemical expansion progressing

    International Nuclear Information System (INIS)

    This paper reports on China's petrochemical expansion surge which is picking up speed. A worldscale petrochemical complex is emerging at Shanghai with an eye to expanding China's petrochemical exports, possibly through joint ventures with foreign companies, China Features reported. In other action, Beijing and Henan province have approved plans for a $1.2 billion chemical fibers complex at the proposed Luoyang refinery, China Daily reported

  2. Ultraprecise thermal expansion measurements of seven low expansion materials

    Science.gov (United States)

    Berthold, J. W., III; Jacobs, S. F.

    1976-01-01

    We summarize a large number of ultraprecise thermal expansion measurements made on seven different low expansivity materials. Expansion coefficients in the -150-300 C temperature range are shown for Owens-Illinois Cer-Vit C-101, Corning ULE 7971 (titanium silicate) and fused silica 7940, Heraeus-Schott Zerodur low-expansion material and Homosil fused silica, Universal Cyclops Invar LR-35, and Simonds Saw and Steel Super Invar.

  3. Immunoelectrophoresis - blood

    Science.gov (United States)

    IEP - serum; Immunoglobulin electrophoresis - blood; Gamma globulin electrophoresis; Serum immunoglobulin electrophoresis ... A blood sample is needed. For information on how this is done, see: Venipuncture

  4. Perioperative neonatal and paediatric blood transfusion

    Directory of Open Access Journals (Sweden)

    Avnish Bharadwaj

    2014-01-01

    Full Text Available Paediatric patients undergoing surgical procedures commonly require some volume of blood or blood component replacement in the perioperative period. Paediatric patients undergoing major surgery associated with substantial blood loss should be evaluated pre-operatively. Pre-operative correction of anaemia may be done considering the age, plasma volume status, clinical status and comorbidities. Maximum allowable blood loss (MABL for surgery must be calculated, and appropriate quantity of blood and blood components should be arranged. Intraoperative monitoring of blood loss should be done, and volume of transfusion should be calculated in a protocol based manner considering the volemia and the trigger threshold for transfusion for the patient and the MABL. Early haemostasis should be achieved by judicious administration of red blood cells, blood components and pharmacological agents.

  5. Renal responses to central vascular expansion are suppressed at night in conscious primates

    Science.gov (United States)

    Kass, D. A.; Sulzman, F. M.; Fuller, C. A.; Moore-Ede, M. C.

    1980-01-01

    The renal and hemodynamic responses of squirrel monkeys to central vascular volume expansion induced by lower body positive pressure (LBPP) during the day and night are investigated. Twelve unanesthetized animals trained to sit in a metabolism chair in which they were restrained only at the waist by a partition separating upper and lower body chambers were subjected to 4 h of continuous LBPP during the day and night, and hemodynamic, urinary and drinking data were monitored. LBPP during day and night is found to induce similar increases in central venous pressure, rises in heart rate and elevations in mean arterial blood pressure. However, although daytime LBPP induced a significant increase in urine flow and sodium excretion, a marked nocturnal inhibition of the renal response to LBPP is observed. Analysis of the time course and circadian regulation patterns of the urinary responses suggests that several separate efferent control pathways are involved.

  6. Exponential Decay of Expansive Constants

    OpenAIRE

    Sun, Peng

    2011-01-01

    A map $f$ on a compact metric space is expansive if and only if $f^n$ is expansive. We study the exponential rate of decay of the expansive constant of $f^n$. A major result is that this rate times box dimension bounds topological entropy.

  7. Patterns of renal dopamine release to regulate diuresis and natriuresis during volume expansion: Role of renal monoamine-oxidase Perfiles de secreción de dopamina renal en la expansión de volumen para regular diuresis y natriuresis: Rol de la monoaminoxidasa renal

    Directory of Open Access Journals (Sweden)

    Verónica de Luca Sarobe

    2010-02-01

    Full Text Available Diuretic and natriuretic effects of renal dopamine (DA are well established. However, in volume expansion the pattern of renal DA release into urine (U DA V and the role of enzymes involved in DA synthesis/degradation have not yet been defined. The objective was to determine the pattern of U DA V during volume expansion and to characterize the involvement of monoamine-oxidase (MAO and aromatic amino-acid decarboxylase (AADC in this response. In this study male Wistar rats were expanded with NaCl 0.9% at a rate of 5% BWt per hour. At the beginning of expansion three groups received a single drug injection as follows: C (vehicle, Control, IMAO (MAO inhibitor Pargyline, 20 mg/kg BWt, i.v. and BNZ (AADC inhibitor Benserazide, 25 mg/kg BWt, i.v.. Results revealed that in C rats U DA V (ng/30 min/100g BWt increased in the first 30 min expansion from 11.5 ± 1.20 to 21.8 ± 3.10 (p La dopamina (DA intrarrenal ejerce efectos diuréticos y natriuréticos. Sin embargo, en los estado de expansión de volumen aún no está bien definido el patrón de liberación de dopamina renal hacia la orina y si cumplen un rol las enzimas involucradas en la síntesis o degradación de la amina. El objetivo del presente trabajo fue determinar el patrón de excreción urinaria de DA (U DA V durante la expansión de volumen, caracterizando la participación de las enzimas monoaminooxidasa (MAO y decarboxilasa de aminoácidos aromáticos (AADC en esta respuesta. Para ello ratas Wistar macho fueron expandidas de volumen con NaCl 0.9% al 5% del peso corporal por hora durante dos horas y divididas en tres grupos, los que al comienzo de la expansión recibieron: C (vehículo, Control, IMAO (Pargilina, inhibidor de MAO, 20 mg/kg PC, i.v. y BNZ (Benserazida, inhibidor de AADC, 25 mg/kg PC, i.v.. Se observó que en C la U DA V (ng/30min/100gPC aumentó durante los primeros 30 minutos de expansión de 11.5 ± 1.20 a 21.8 ± 3.10 (p < 0.05, disminuyendo posteriormente. IMAO mostr

  8. Rethinking expansive learning

    DEFF Research Database (Denmark)

    Kolbæk, Ditte; Lundh Snis, Ulrika

    Abstract: This paper analyses an online community of master’s students taking a course in ICT and organisational learning. The students initiated and facilitated an educational design for organisational learning called Proactive Review in the organisation where they are employed. By using an online...... discussion forum on Google groups, they created new ways of reflecting and learning. We used netnography to select qualitative postings from the online community and expansive learning concepts for data analysis. The findings show how students changed practices of organisational learning in their...

  9. Engineering Properties of Expansive Soil

    Institute of Scientific and Technical Information of China (English)

    DAI Shaobin; SONG Minghai; HUANG Jun

    2005-01-01

    The components of expansive soil were analyzed with EDAX, and it is shown that the main contents of expansive soil in the northern Hubei have some significant effects on engineering properties of expansive soil. Furthermore, the soil modified by lime has an obvious increase of Ca2+ and an improvement of connections between granules so as to reduce the expansibility and contractility of soil. And it also has a better effect on the modified expansive soil than the one modified by pulverized fuel ash.

  10. Technical efficiency of blood component preparation in blood centres of 10 European countries

    OpenAIRE

    Veihola, Marketta

    2008-01-01

    Various reasons, such as ethical issues in maintaining blood resources, growing costs, and strict requirements for safe blood, have increased the pressure for efficient use of resources in blood banking. The competence of blood establishments can be characterized by their ability to predict the volume of blood collection to be able to provide cellular blood components in a timely manner as dictated by hospital demand. The stochastically varying clinical need for platelets (PLTs) sets a specif...

  11. Modelling autogenous expansion for magnesia concrete in arch dams

    Institute of Scientific and Technical Information of China (English)

    Feng JIN; Guoxin ZHANG; Xiaoqing LUO; Chuhan ZHANG

    2008-01-01

    Magnesia Concrete is a kind of expansive con-crete used in Chinese hydraulic engineering more and more widely. To evaluate the effects of autogenous expan-sion on the stresses of arch dams, a simple model of auto-genous expansion for Magnesia Concrete in dam engineering is presented. This model is based on three assumptions: 1) the total amount of autogenous expan-sion of Magnesia Concrete is related only to the properties of materials and mixing of concrete; 2) the autogenous expansion of Magnesia Concrete is irreversible due to the irreversibility of hydration reaction of Magnesia in the concrete; 3) the autogenous expansion strain rates of Magnesia Concrete bear a relation between temperature and residual Magnesia per unit volume of concrete. The model is verified by some experimental data of autogen-ous expansion of Magnesia Concrete and field-measured data of an arch dam in China. Embedded into finite ele-ment arch dam simulation software, this model is employed to simulate the effects of autogenous expansion of Magnesia Concrete in hydraulic engineering.

  12. Artificial blood

    Directory of Open Access Journals (Sweden)

    Sarkar Suman

    2008-01-01

    Full Text Available Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  13. Use of blood and blood products.

    Science.gov (United States)

    Hunt, E; Wood, B

    1999-11-01

    It is sometimes necessary for the practitioner to transfuse the ruminant with whole blood or plasma. These techniques are often difficult to perform in practice, are time-consuming, expensive, and stressful to the animal. Acute loss of 20% to 25% of the blood volume will result in marked clinical signs of anemia, including tachycardia and maniacal behavior. The PCV is only a useful tool with which to monitor acute blood loss after intravascular equilibration with other fluid compartments has occurred. An acutely developing PCV of 15% or less may require transfusion. Chronic anemia with PCV of 7% to 12% can be tolerated without transfusion if the animal is not stressed and no further decline in erythrocyte mass occurs. Seventy-five percent of transfused bovine erythrocytes are destroyed within 48 hours of transfusion. A transfusion rate of 10 to 20 mL/kg recipient weight is necessary to result in any appreciable increase in PCV. A nonpregnant donor can contribute 10 to 15 mL of blood/kg body weight at 2- to 4-week intervals. Sodium citrate is an effective anticoagulant, but acid citrate dextrose should be used if blood is to be stored for more than a few hours. Blood should not be stored more than 2 weeks prior to administration. Heparin is an unsuitable anticoagulant because the quantity of heparin required for clot-free blood collection will lead to coagulation defects in the recipient. Blood cross-matching is only rarely performed in the ruminant. In field situations, it is advisable to inject 200 mL of donor blood into the adult recipient and wait 10 minutes. If no reaction occurs, the rest of the blood can probably be safely administered as long as volume overload problems do not develop. Adverse reactions are most commonly seen in very young animals or pregnant cattle. Signs of blood or plasma transfusion reaction include hiccoughing, tachycardia, tachypnea, sweating, muscle tremors, pruritus, salivation, cough, dyspnea, fever, lacrimation, hematuria

  14. Blood smear

    Science.gov (United States)

    ... osmotic fragility ) Deficiency of an enzyme called lecithin cholesterol acyl transferase Abnormalities of hemoglobin , the protein in ... sickle and Pappenheimer Red blood cells, target cells Formed elements of blood References Bain BJ. The peripheral ...

  15. Burial Ground Expansion Hydrogeologic Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Gaughan , T.F.

    1999-02-26

    Sirrine Environmental Consultants provided technical oversight of the installation of eighteen groundwater monitoring wells and six exploratory borings around the location of the Burial Ground Expansion.

  16. Frequency dependent thermal expansion in binary viscoelasticcomposites

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, James G.

    2007-12-01

    The effective thermal expansion coefficient beta* of abinary viscoelastic composite is shown to be frequency dependent even ifthe thermal expansion coefficients beta A and beta B of both constituentsare themselves frequency independent. Exact calculations for binaryviscoelastic systems show that beta* is related to constituent valuesbeta A, beta B, volume fractions, and bulk moduli KA, KB, as well as tothe overall bulk modulus K* of the composite system. Then, beta* isdetermined for isotropic systems by first bounding (or measuring) K* andtherefore beta*. For anisotropic systems with hexagonal symmetry, theprincipal values of the thermal expansion beta*perp and beta*para can bedetermined exactly when the constituents form a layered system. In allthe examples studied, it is shown explicitly that the eigenvectors of thethermoviscoelastic system possess non-negative dissipation -- despite thecomplicated analytical behavior of the frequency dependent thermalexpansivities themselves. Methods presented have a variety ofapplications from fluid-fluid mixtures to fluid-solid suspensions, andfrom fluid-saturated porous media to viscoelastic solid-solidcomposites.

  17. EQUIVALENT MODEL OF EXPANSION OF CEMENT MORTAR UNDER SULPHATE EROSION

    Institute of Scientific and Technical Information of China (English)

    Jue Zhu; Minqiang Jiaug; Jiankang Chen

    2008-01-01

    The expansion property of cement mortar under the attack of sulfate ions is studied by experimental and theoretical methods.First,cement mortars are fabricated with the ratio of water to cement of 0.4,0.6,and 0.8.Secondly,the expansion of specimen immerged in sulphate solution is measured at different times.Thirdly,a theoretical model of expansion of cement mortar under sulphate erosion is suggested by virtue of represent volume element method.In this model, the damage evolution due to the interaction between delayed ettringite and cement mortar is taken into account.Finally,the numerical calculation is performed.The numerical and experimental results indicate that the model perfectly describes the expansion of the cement mortar.

  18. Mechanism of actuation in conducting polymers: Osmotic expansion

    DEFF Research Database (Denmark)

    Bay, Lasse; Jacobsen, Torben; West, Keld;

    2001-01-01

    Conducting polymers expand or contract when their redox state is changed. This expansion/contraction effect can be separated in an intrinsic part because of changes of the polymer backbone on reduction/oxidation and a part depending on the surrounding electrolyte phase, because of osmotic expansi...... and designing actuator experiments and when comparing experimental results from different sources.......Conducting polymers expand or contract when their redox state is changed. This expansion/contraction effect can be separated in an intrinsic part because of changes of the polymer backbone on reduction/oxidation and a part depending on the surrounding electrolyte phase, because of osmotic expansion...... of the polymer phase. The osmotic effect causes solvent molecules to move into the polymer in a number far in excess of those bound strongly in the solvation shell of the mobile ion, resulting in large volume changes. In this paper, a thermodynamic description of the osmotic expansion is worked out. The model...

  19. Volume Entropy

    OpenAIRE

    Astuti, Valerio; Christodoulou, Marios; Rovelli, Carlo

    2016-01-01

    Building on a technical result by Brunnemann and Rideout on the spectrum of the Volume operator in Loop Quantum Gravity, we show that the dimension of the space of the quadrivalent states --with finite-volume individual nodes-- describing a region with total volume smaller than $V$, has \\emph{finite} dimension, bounded by $V \\log V$. This allows us to introduce the notion of "volume entropy": the von Neumann entropy associated to the measurement of volume.

  20. Orthogonal Query Expansion

    CERN Document Server

    Ackerman, Margareta; Lopez-Ortiz, Alejandro

    2011-01-01

    Over the last fifteen years, web searching has seen tremendous improvements. Starting from a nearly random collection of matching pages in 1995, today, search engines tend to satisfy the user's informational need on well-formulated queries. One of the main remaining challenges is to satisfy the users' needs when they provide a poorly formulated query. When the pages matching the user's original keywords are judged to be unsatisfactory, query expansion techniques are used to alter the result set. These techniques find keywords that are similar to the keywords given by the user, which are then appended to the original query leading to a perturbation of the result set. However, when the original query is sufficiently ill-posed, the user's informational need is best met using entirely different keywords, and a small perturbation of the original result set is bound to fail. We propose a novel approach that is not based on the keywords of the original query. We intentionally seek out orthogonal queries, which are r...

  1. Radiolabelled Cellular Blood Elements

    International Nuclear Information System (INIS)

    This volume contains the abstracts of the 5th International Symposion on Radiolabelling of Cellular Blood Elements to be held in Vienna, Austria, September 10-14, 1989. The Meeting is the fifth in a series of meetings designed to discuss the basics and clinical application of radiolabelling techniques. In these days, beside the search for new labelling agents and extending the knowledge in clinical use, the use of monoclonal antibodies is a big new challenge. All reviewed contributions that have been accepted for presentation are contained in this volume. (authors) 58 of them are of INIS scope

  2. Cord Blood

    Directory of Open Access Journals (Sweden)

    Saeed Abroun

    2014-05-01

    Full Text Available   Stem cells are naïve or master cells. This means they can transform into special 200 cell types as needed by body, and each of these cells has just one function. Stem cells are found in many parts of the human body, although some sources have richer concentrations than others. Some excellent sources of stem cells, such as bone marrow, peripheral blood, cord blood, other tissue stem cells and human embryos, which last one are controversial and their use can be illegal in some countries. Cord blood is a sample of blood taken from a newborn baby's umbilical cord. It is a rich source of stem cells, umbilical cord blood and tissue are collected from material that normally has no use following a child’s birth. Umbilical cord blood and tissue cells are rich sources of stem cells, which have been used in the treatment of over 80 diseases including leukemia, lymphoma and anemia as bone marrow stem cell potency.  The most common disease category has been leukemia. The next largest group is inherited diseases. Patients with lymphoma, myelodysplasia and severe aplastic anemia have also been successfully transplanted with cord blood. Cord blood is obtained by syringing out the placenta through the umbilical cord at the time of childbirth, after the cord has been detached from the newborn. Collecting stem cells from umbilical blood and tissue is ethical, pain-free, safe and simple. When they are needed to treat your child later in life, there will be no rejection or incompatibility issues, as the procedure will be using their own cells. In contrast, stem cells from donors do have these potential problems. By consider about cord blood potency, cord blood banks (familial or public were established. In IRAN, four cord blood banks has activity, Shariati BMT center cord blood bank, Royan familial cord blood banks, Royan public cord blood banks and Iranian Blood Transfusion Organ cord blood banks. Despite 50,000 sample which storage in these banks, but the

  3. The clot burden score, the Boston Acute Stroke Imaging Scale, the cerebral blood volume ASPECTS, and two novel imaging parameters in the prediction of clinical outcome of ischemic stroke patients receiving intravenous thrombolytic therapy

    International Nuclear Information System (INIS)

    Recently two classification methods based on the location and the extent of thrombosis detected with CT angiography have been introduced: the Boston Acute Stroke Imaging Scale (BASIS) and the clot burden score (CBS). We studied the performance of BASIS and CBS in predicting good clinical outcome (mRS ≤2 at 90 days) in an acute (<3 h) stroke cohort treated with intravenous thrombolytic therapy. Eighty-three consecutive patients who underwent multimodal CT were analyzed. Binary logistic regression model was used to assess how BASIS, CBS, and cerebral blood volume (CBV) ASPECTS predict favorable clinical outcome. Diagnostic sensitivities and specificities were calculated and compared. Patients with low CBS and CBV ASPECTS scores and major strokes according to BASIS had significantly higher admission NIHSS scores, larger perfusion defects, and more often poor clinical outcome. In logistic regression analysis, CBV ASPECTS, CBS and BASIS were significantly associated with the clinical outcome. The performance of BASIS improved when patients with thrombosis of the M2 segment of the middle cerebral artery were classified as having minor stroke (M1-BASIS). In the anterior circulation, the sum of CBS and CBV ASPECTS (CBSV) proved to be the most robust predictor of favorable outcome. CBV ASPECTS and CBS had high sensitivity but moderate to poor specificity while BASIS was only moderately sensitive and specific. CBS, BASIS, and CBV ASPECTS are statistically robust and sensitive but unspecific predictors of good clinical outcome. Two new derived imaging parameters, CBSV and M1-BASIS, share these properties and may have increased prognostic value. (orig.)

  4. The clot burden score, the Boston Acute Stroke Imaging Scale, the cerebral blood volume ASPECTS, and two novel imaging parameters in the prediction of clinical outcome of ischemic stroke patients receiving intravenous thrombolytic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sillanpaa, Niko; Hakomaki, Jari; Lahteela, Arto; Dastidar, Prasun; Soimakallio, Seppo [Tampere University Hospital, Medical Imaging Center, Tampere (Finland); Saarinen, Jukka T.; Numminen, Heikki; Elovaara, Irina [Tampere University Hospital, Department of Neurology, Tampere (Finland); Rusanen, Harri [Oulu University Hospital, Department of Neurology, Oulu (Finland)

    2012-07-15

    Recently two classification methods based on the location and the extent of thrombosis detected with CT angiography have been introduced: the Boston Acute Stroke Imaging Scale (BASIS) and the clot burden score (CBS). We studied the performance of BASIS and CBS in predicting good clinical outcome (mRS {<=}2 at 90 days) in an acute (<3 h) stroke cohort treated with intravenous thrombolytic therapy. Eighty-three consecutive patients who underwent multimodal CT were analyzed. Binary logistic regression model was used to assess how BASIS, CBS, and cerebral blood volume (CBV) ASPECTS predict favorable clinical outcome. Diagnostic sensitivities and specificities were calculated and compared. Patients with low CBS and CBV ASPECTS scores and major strokes according to BASIS had significantly higher admission NIHSS scores, larger perfusion defects, and more often poor clinical outcome. In logistic regression analysis, CBV ASPECTS, CBS and BASIS were significantly associated with the clinical outcome. The performance of BASIS improved when patients with thrombosis of the M2 segment of the middle cerebral artery were classified as having minor stroke (M1-BASIS). In the anterior circulation, the sum of CBS and CBV ASPECTS (CBSV) proved to be the most robust predictor of favorable outcome. CBV ASPECTS and CBS had high sensitivity but moderate to poor specificity while BASIS was only moderately sensitive and specific. CBS, BASIS, and CBV ASPECTS are statistically robust and sensitive but unspecific predictors of good clinical outcome. Two new derived imaging parameters, CBSV and M1-BASIS, share these properties and may have increased prognostic value. (orig.)

  5. Exponential Expansion in Evolutionary Economics

    DEFF Research Database (Denmark)

    Frederiksen, Peter; Jagtfelt, Tue

    2013-01-01

    this problem is proposed in the form of a model of exponential expansion. The model outlines the overall structure and function of the economy as exponential expansion. The pictographic model describes four axiomatic concepts and their exponential nature. The interactive, directional, emerging and...

  6. Warp Drive With Zero Expansion

    OpenAIRE

    Natario, Jose

    2001-01-01

    It is commonly believed that Alcubierre's warp drive works by contracting space in front of the warp bubble and expanding space behind it. We show that this expansion/contraction is but a marginal consequence of the choice made by Alcubierre, and explicitly construct a similar spacetime where no contraction/expansion occurs. Global and optical properties of warp drive spacetimes are also discussed.

  7. On summation of perturbation expansions

    International Nuclear Information System (INIS)

    The problem of the restoration of physical quantities defined by divergent perturbation expansions is analysed. The Pad'e and Borel summability is proved for alternating perturbation expansions with factorially growing coefficients. The proof is based on the methods of the classical moments theory. 17 refs. (author)

  8. Asymptotic expansions of Jacobi functions

    International Nuclear Information System (INIS)

    The author presents an asymptotic expansion of the Jacobi polynomials which is based on the fact, that these polynomials are special hypergeometric functions. He uses an integral representation of these functions and expands the integrand in a power series. He derives explicit error bounds on this expansion. (HSI)

  9. 尼卡地平联合羟乙基淀粉容量填充对单纯静脉麻醉丙泊酚用量的影响观察%Effects of nicardipine,hydroxyethyl starch combined with volume expansion on propofol dosage during total intravenous anesthesia

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    Objective To investigate the effects of nicardipine hydroxyethyl starch combined with volume expansion on propofol dosage during total intravenous anesthesia. Methods 87 patients undergoing spinal surgery were randomly divided observation group(47 cases) and control group(40 cases). All patients received volume expansion with hydroxyethyl starch 10ml/kg in 20min after giving nicardipine. At 1 min before tracheal intubation,the patients were given a bolus of nicardipine 10μg/kg(observation group) or normal saline(control group), observation group received 10μg/kg nicardipine followed by infusion of 1μg·kg-1·min-1, while control group received the same volume of saline. Anesthesia was maintained with target-controlled by propofol BIS was contolled between 40-60. The consumption of propofol, recovery of consciousness and trachea extubation were recorded. Results The propofol dosage of observation group(850.7±139.3ml), waking hours(6.2±2.5) and extubation time(8.1±2.6) significantly less than in the control group, the difference was statistically significant(P <0.05); The observation group MAP average was 82.5±15.7, was obviously lower than the control group 93.5±17.6, it is statistically significant difference(P <0.05); Observation group HR averages 90.6±10.5, is significantly higher than control group 75.3±11.5, difference has statistical significance(P <0.05); Observation group intraoperative propofol concentration average and BIS average are 2.5±0.4μg/ml and 52.8±3.4, has difference with control group(P <0.05). Conclusion Nicardipine combined with hydroxyethyl starch on the volume expansion during induction could reduce cardiovascular respone, decrease propofol consumption and shorten the time of consciousness recovery and extubation in total intravenous anesthesia.%  目的观察尼卡地平联合羟乙基淀粉容量填充对单纯静脉麻醉丙泊酚用量的影响。方法将87例择期进行脊柱手术患者随机分为对照组40

  10. On genus expansion of superpolynomials

    CERN Document Server

    Mironov, A; Sleptsov, A; Smirnov, A

    2013-01-01

    Recently it was shown that the (Ooguri-Vafa) generating function of HOMFLY polynomials is the Hurwitz partition function, i.e. that the dependence of the HOMFLY polynomials on representation is naturally captured by symmetric group characters (cut-and-join eigenvalues). The genus expansion and expansion through Vassiliev invariants explicitly demonstrate this phenomenon. In the present letter we claim that the superpolynomials are not functions of such a type: symmetric group characters do not provide an adequate linear basis for their expansions. Deformation to superpolynomials is, however, straightforward in the multiplicative basis:the Casimir operators are beta-deformed to Hamiltonians of the Calogero-Moser-Sutherland system. Applying this trick to the genus and Vassiliev expansions, we observe that the deformation is rather straightforward only for the thin knots. Beyond this family additional algebraically independent terms appear in the Vassiliev and genus expansions. This can suggest that the superpol...

  11. Cluster expansion for ferrofluids and the influence of polydispersity on magnetization

    CERN Document Server

    Huke, B

    2002-01-01

    We present the results of a cluster expansion calculation for a ferrofluid modeled as a system of monodisperse or polydisperse dipolar hard spheres. The magnetization is obtained as series expansion in terms of (i) the volume fraction phi and (ii) a dimensionless dipolar coupling constant epsilon. A detailed calculation for the monodisperse case can be found in Phys. Rev. E 62 (2000) 6875.

  12. Blood / Money

    OpenAIRE

    Strong, Thomas

    1997-01-01

    Marilyn Strathern has argued that "nature" in Euro-American culture has appeared as constraint; it has figured the givens of existence on which human artifice is seen to construct "society" or "culture."(5) Among those givens is the notion that human beings are naturally individuals. And blood, too, images individuality: "The very thought of blood, individual blood, touches the deepest feelings in man about life and death" ([RIchard Titmuss] 16.) Transfusion medicine, then, draws on a series ...

  13. Blood donor management in china.

    Science.gov (United States)

    Shi, Ling; Wang, Jingxing; Liu, Zhong; Stevens, Lori; Sadler, Andrew; Ness, Paul; Shan, Hua

    2014-07-01

    Despite a steady increase in total blood collections and voluntary non-remunerated blood donors, China continues to have many challenges with its blood donation system. The country's donation rate remains low at 9%o, with over 60% of donors being first-time donors. Generally there is a lack of adequate public awareness about blood donation. The conservative donor selection criteria, the relatively long donation interval, and the small donation volume have further limited blood supply. To ensure a sufficient and safe blood supply that meets the increasing clinical need for blood products, there is an urgent need to strengthen the country's blood donor management. This comprehensive effort should include educating and motivating more individuals especially from the rural areas to be involved in blood donation, developing rational and evidence-based selection criteria for donor eligibility, designing a donor follow-up mechanism to encourage more future donations, assessing the current donor testing strategy, improving donor service and care, building regional and national shared donor deferral database, and enhancing the transparency of the blood donation system to gain more trust from the general public. The purpose of the review is to provide an overview of the key process of and challenges with the blood donor management system in China. PMID:25254023

  14. Tissue regeneration during tissue expansion and choosing an expander

    Directory of Open Access Journals (Sweden)

    K Agrawal

    2012-01-01

    Full Text Available This paper reviews the various aspects of tissue regeneration during the process of tissue expansion. "Creep" and mechanical and biological "stretch" are responsible for expansion. During expansion, the epidermis thickens, the dermis thins out, vascularity improves, significant angiogenesis occurs, hair telogen phase becomes shorter and the peripheral nerves, vessels and muscle fibres lengthen. Expansion is associated with molecular changes in the tissue. Almost all these biological changes are reversible after the removal of the expander.This study is also aimed at reviewing the difficulty in deciding the volume and dimension of the expander for a defect. Basic mathematical formulae and the computer programmes for calculating the dimension of tissue expanders, although available in the literature, are not popular. A user-friendly computer programme based on the easily available Microsoft Excel spread sheet has been introduced. When we feed the area of defect and base dimension of the donor area or tissue expander, this programme calculates the volume and height of the expander. The shape of the expander is decided clinically based on the availability of the donor area and the designing of the future tissue movement. Today, tissue expansion is better understood biologically and mechanically. Clinical judgement remains indispensable in choosing the size and shape of the tissue expander.

  15. Volume geodesic distortion and Ricci curvature for Hamiltonian dynamics

    OpenAIRE

    Agrachev, Andrei; Barilari, Davide; Elisa, Paoli

    2016-01-01

    We study the variation of a smooth volume form along extremals of a variational problem with nonholonomic constraints and an action-like Lagrangian. We introduce a new invariant describing the interaction of the volume with the dynamics and we study its basic properties. We then show how this invariant, together with curvature-like invariants of the dynamics, appear in the expansion of the volume at regular points of the exponential map. This generalizes the well-known expansion of the Rieman...

  16. Understanding Blood Counts

    Science.gov (United States)

    ... Lab and Imaging Tests Understanding Blood Counts Understanding Blood Counts Understanding Blood Counts SHARE: Print Glossary Blood cell counts give ... your blood that's occupied by red cells. Normal Blood Counts Normal blood counts fall within a range ...

  17. Thermal expansion of solid solutions in apatite binary systems

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, Alexander V.; Bulanov, Evgeny N., E-mail: bulanoven@gmail.com; Korokin, Vitaly Zh.

    2015-01-15

    Graphical abstract: Thermal dependencies of volume thermal expansion parameter for with thermal expansion diagrams for Pb{sub 5}(PO{sub 4}){sub 3}F{sub x}Cl{sub 1−x}. - Highlights: • Solid solutions in three apatitic binary systems were investigated via HT-XRD. • Thermal expansion coefficients of solid solutions in the systems were calculated. • Features of the thermal deformation of the apatites were described. • Termoroentgenography is a sensitive method for the investigation of isomorphism. - Abstract: High-temperature insitu X-ray diffraction was used to investigate isomorphism and the thermal expansion of apatite-structured compounds in three binary systems in the entire temperature range of the existence of its hexagonal modifications. Most of the studied compounds are highly expandable (α{sub l} > 8 × 10{sup 6} (K{sup −1})). In Pb{sub 5}(PO{sub 4}){sub 3}F–Pb{sub 5}(PO{sub 4}){sub 3}Cl system, volume thermal expansion coefficient is independence from the composition at 573 K. In Pb{sub 5}(PO{sub 4}){sub 3}Cl–Pb{sub 5}(VO{sub 4}){sub 3}Cl, the compound with equimolar ratio of substituted atoms has constant volume thermal expansion coefficient in temperature range 298–973 K. Ca{sub 5}(PO{sub 4}){sub 3}Cl–Pb{sub 5}(PO{sub 4}){sub 3}Cl system is characterized by the most thermal sensitive composition, in which there is an equal ratio of isomorphic substituted atoms.

  18. Plaquette expansion proof and interpretation

    International Nuclear Information System (INIS)

    The plaquette expansion, a general non-perturbative method for calculating the properties of lattice Hamiltonian systems, is established up to the first two orders for an arbitrary system. This method employs an expansion of the Lanczos coefficients, the tridiagonal Hamiltonian matrix elements or equivalently the continued fraction coefficients of the resolvent, in a descending series in the size of the system. The coefficients of this series are formed from the low order cumulants or connected Hamiltonian moments. The lowest order approximation in the plaquette expansion corresponds to a Gaussian model which is a consequence of the control limit theorem. 7 refs

  19. 人脐血造血干/祖细胞的生物反应器大规模扩增及移植实验%Expansion of hematopoietic stem/progenitor cells of cord blood by bioreactor and the transplantation into NOD/SCID mice

    Institute of Scientific and Technical Information of China (English)

    毛平; 段华新; 王彩霞; 李迎霄; 邓婷芬; 许艳丽; 罗畅如

    2009-01-01

    Objective To expand hematopoietic stem/progenitor cells of cord blood in large scale by bioreactor. Methods Mononuclear cells from human umbilical cord blood were cultured in serum-free medium with stem cell factor (SCF), flt-3 ligand (FL3) and thrombopoietin (TPO). The expansion fold of cells, colony-forming and expression of surface molecules were analyzed by cell counting, colony-forming assay and flow cytometry, respectively. And the engraftment of these expanded cells was studied through cell transplantation into irradiated non-obese diabetic/severe-combined immunodeficient (NOD/SCID) mice. Results After culture for 7 days,the folds of total cell expansion in bioreactor were higher than those in static culture, P0.05). The cells expanded in bioreactor were successfully engrafted into irradiated NOD/SCID mice and reconstructed the multi-lineage hematopoiesis. Conclusion The bioreactor favors large-scale expansion of hematopoietic progenitor cells and keeps the hematopoietic repopulation potential.%目的 利用生物反应器大规模扩增人脐血造血干/祖细胞,并通过动物移植实验检验该方法的有效性.方法 采集抗凝脐血10份,分离出单个核细胞(MNC),分别进行生物反应器扩增培养和静态扩增培养.检测扩增前后细胞表面CD34、CD38、CD133、CD184和CD62L分子的表达,并进行造血干/祖细胞集落的培养.取非肥胖糖尿病重症联合免疫缺陷小鼠,以X射线照射后,分为4组,其中MNC组小鼠注射未经扩增培养的MNC;静态扩增组小鼠注射经过静态扩增培养的细胞;反应器扩增组小鼠注射经过生物反应器扩增培养的细胞;空白对照组小鼠注射生理盐水.移植后6周处死存活小鼠,收集骨髓细胞,检测其中CD45+、CD3+、CD19+和CD33+细胞的含量以及人特异的Cart-Ⅰ和Alu基因的表达.结果 生物反应器扩增前MNC为(1.2~2.8)×108个,扩增后为(3.7~12.6)×108个,扩增后的细胞数明显高于静态扩增培养者(P<0

  20. Thermal expansion and phase transitions of α-AlF{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Morelock, Cody R.; Hancock, Justin C. [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400 (United States); Wilkinson, Angus P., E-mail: angus.wilkinson@chemistry.gatech.edu [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400 (United States); School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0245 (United States)

    2014-11-15

    ReO{sub 3}-type materials are of interest for their potential low or negative thermal expansion. Many metal trifluorides MF{sub 3} adopt the cubic form of this structure at elevated temperatures, which rhombohedrally distorts upon cooling. The rhombohedral form displays strong positive volume thermal expansion, but cubic MF{sub 3} display much lower and sometimes negative thermal expansion. The expansion behavior of α-AlF{sub 3} was characterized via synchrotron powder diffraction between 323 and 1177 K. α-AlF{sub 3} is rhombohedral at ambient conditions and displays strongly anisotropic thermal expansion. The volume coefficient of thermal expansion (CTE), α{sub V}, at 500 K is ∼86 ppm K{sup −1}, but the linear CTE along the c-axis, α{sub c}, is close to zero. α-AlF{sub 3} becomes cubic on heating to ∼713 K and continues to show positive thermal expansion above the phase transition (α{sub V}(900 K) ∼25 ppm K{sup −1}). - Graphical abstract: α-AlF{sub 3} has a rhombohedrally distorted ReO{sub 3}-type structure at ambient conditions and displays strongly positive volume thermal expansion that is highly anisotropic; the material becomes cubic on heating above ∼713 K and continues to show positive thermal expansion. - Highlights: • ReO{sub 3}-type α-AlF{sub 3} displays strongly anisotropic thermal expansion below 713 K. • α-AlF{sub 3} is cubic above 713 K and maintains positive (isotropic) thermal expansion. • The volume CTE changes from ∼86 to ∼25 ppm K{sup −1} on heating from 500 to 900 K. • The PTE of cubic α-AlF{sub 3} may be due to the presence of local octahedral tilts.

  1. Blood donation

    CERN Multimedia

    GS Department

    2009-01-01

    A blood donation is organised by the Cantonal Hospital of Geneva On Thursday 19 March 2009 from 9 a.m. to 5 p.m. CERN RESTAURANT 2 Number of donations during the last blood donations :135 donors in July 2008 122 donors in November 2008 Let’s do better in 2009 !!! Give 30 minutes of your time to save lives...

  2. BLOOD DONATION

    CERN Multimedia

    SC Unit

    2008-01-01

    A blood donation, organized by EFS (Etablissement Français du Sang) of Annemasse will take place On Wednesday 12 November 2008, from 8:30 to 16:00, at CERN Restaurant 2 If possible, please, bring your blood group Card.

  3. Study on Expansion Cracking of Hydration in Concrete Aggregates

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In accordance with a fresh accident by severe expansion cracks of structural elements,based on systematic detection and analyses such as X-ray diffraction,differential thermal analysis,scanning electron microscory,chemical analysis,petrographic analysis, electronic probe analysis,and atomic absorption spectroscopy analysis, it is pointed out that the dominant reasons lie in the hydration reaction of magnesia in concrete aggregates, resulting in a volume expansion in structure members.A wholly new corresponding strengthening method is applied to the cracked elements and turned out to be effective.

  4. Tainted blood

    DEFF Research Database (Denmark)

    Deleuran, Ida; Sheikh, Zainab Afshan; Hoeyer, Klaus

    2015-01-01

    study of the historical rise and current workings of safety practices in the Danish blood system. Here, we identify a strong focus on contamination in order to avoid 'tainted blood', at the expense of working with risks that could be avoided through enhanced blood monitoring practices. Of further...... significance to this focus are the social dynamics found at the heart of safety practices aimed at avoiding contamination. We argue that such dynamics need more attention, in order to achieve good health outcomes in transfusion medicine. Thus, we conclude that, to ensure continuously safe blood systems, we...... need to move beyond the bifurcation of the social and medical aspects of blood supply as two separate issues and approach social dynamics as key medical safety questions....

  5. Volume-to-volume registration

    OpenAIRE

    Harg, Erik

    2005-01-01

    Implementation of automated volume-to-volume registration applications for three separate registration steps desired in enhancing neurosurgical navigation is considered. Prototype implementations for MRI-to-MRI registration, MRI-to-US registration and US-to-US registration have been made using registration methods available in the Insight Toolkit, with variants of the Mutual Information similarity metric. The obtained results indicate that automatic volume-to-volume registration using Normali...

  6. Study on the Correlation of Central Venous Pressure with Intrathoracic Blood Volume Index and Global End-Diastolic Volume Index after Pulmonary Lobectomy%肺手术后中心静脉压与血容量指数、全心舒张末期容积指数的相关性研究

    Institute of Scientific and Technical Information of China (English)

    王素梅; 黎阳; 黄冰; 茅乃权; 阮林; 彭丹晖; 杜学柯

    2013-01-01

    Objective To investigate the correlation of central venous pressure ( CVP ) with intrathoracic blood volume index(ITBVI) and global end-diastolic volume index(GEDVI) after pulmonary lobectomy,and to dis-cuss the value of CVP as a parameter of volume load after pulmonary lobectomy .Methods Twenty-three cases of ASA I-II grade lung cancer who underwent radical resection were enrolled in the study .Pulse indicator continuous cardiac output ( PiCCO) monitoring technology was used to record their postoperative CVP ,GEDVI and ITBVI at the time of off-lining(T1),after tracheal extubation instantly(T2),2 hours after extubation(T3),5 hours after extubation ( T4 ) ,and 15 hours after extubation ( T5 ) .The correlation of CVP with ITBVI and GEDVI was analyzed .Results The correlation coefficient of CVP and GEDVI was equal to -0 .138 ( P>0 .05 ); The correlation coefficient of CVP and ITBVI was equal to -0.153(P>0.05).Conclusion CVP can not indicate the volume load of patients after pulmonary lobectomy .It should be based on the clinical features or using more monitoring techniques when performing load monitoring and evaluation .%目的:探讨肺手术患者术后胸腔内血容量指数( ITBVI)、全心舒张末期容积指数( GEDVI)与中心静脉压( CVP)的相关性,研究肺手术后CVP用于评价肺手术后容量负荷的价值。方法 ASAⅠ~Ⅱ级行肺癌根治术患者23例,术后应用脉搏指示剂心排量连续监测( PiCCO)技术监测患者脱机后( T1)、拔管后( T2)、拔管后2h(T3)、拔管后5 h(T4)、拔管后15 h(T5)的CVP、ITBVI、GEDVI,分析CVP与ITBVI、GEDVI的相关性。结果 CVP与GEDVI的相关系数为r=-0.138(P>0.05); CVP与ITBVI r为-0.153(P>0.05)。结论CVP不能反映肺手术后机体的容量状态,在容量监测与评估时要根据临床表现或增加其他监测手段。

  7. Gradient expansion for anisotropic hydrodynamics

    CERN Document Server

    Florkowski, Wojciech; Spaliński, Michał

    2016-01-01

    We compute the gradient expansion for anisotropic hydrodynamics. The results are compared with the corresponding expansion of the underlying kinetic-theory model with the collision term treated in the relaxation time approximation. We find that a recent formulation of anisotropic hydrodynamics based on an anisotropic matching principle yields the first three terms of the gradient expansion in agreement with those obtained for the kinetic theory. This gives further support for this particular hydrodynamic model as a good approximation of the kinetic-theory approach. We further find that the gradient expansion of anisotropic hydrodynamics is an asymptotic series, and the singularities of the analytic continuation of its Borel transform indicate the presence of non-hydrodynamic modes.

  8. Breast Reconstruction with Tissue Expansion

    Medline Plus

    Full Text Available ... come to my practice a few months ago seeking a left breast reconstruction after mastectomy. She had ... Veritas Collagen Matrix sling in order to help support the expansion because there is possible radiation damage ...

  9. Binomial expansions modulo prime powers

    Directory of Open Access Journals (Sweden)

    Paul W. Haggard

    1980-01-01

    Full Text Available In this note a result is given and proved concerning binomial expansions modulo prime powers. In the proof congruence modulo prime powers is generalized to the rational numbers via valuations.

  10. Diagnosis of pulmonary contusion by CT scan for patients with volume efficiency of pulmonary blood%肺血容积效应合并肺挫裂伤的CT诊断分析

    Institute of Scientific and Technical Information of China (English)

    曹结水; 张新民

    2014-01-01

    Objective:To explore characteristics of pulmonary contusion by CT scan for patients with volume effi-ciency of pulmonary blood. Methods:A serial of 46 patients with thoracic trauma who were found with high dense im-age by supine CT scan were scanned again in the lateral prone position. CT findings were compared between the supine position and the lateral prone position. Results:Among 46 patients with thoracic trauma, pulmonary contusion was diagnosed in 12 patients by CT scan in the supine position and 26 patients in the lateral prone position. The posi-tive rate of pulmonary contusion by CT scan was significantly higher in the lateral prone position than that in the supine position group (P<0.05). Conclusions:CT scan in the lateral prone position is superior to that in the supine po-sition for diagnosis of pulmonary contusion in patients with thoracic trauma.%目的:探讨肺血容积效应合并肺挫裂伤的CT表现。方法:对46例胸部外伤仰卧位平扫见肺部背侧高密度影患者,再行侧卧位或俯卧位扫描,分析肺血容积效应合并肺挫裂伤的CT特征。结果:46例肺血容积效应患者中仰卧位发现12例合并肺挫裂伤,侧、俯卧扫描患者中发现26例合并肺挫裂伤,差异具有统计学意义(P<0.05)。结论:侧、俯卧位扫描在肺血容积效应合并肺挫裂伤中有诊断意义,避免误诊和漏诊。

  11. Relationship between cerebral infarct volume and peripheral blood lymphocyte DNA damage%脑梗死体积与外周血淋巴细胞DNA损伤的关系

    Institute of Scientific and Technical Information of China (English)

    鲁文果; 姜丹; 范德义; 张苏明

    2012-01-01

    Objective To study the relationship between cerebral infarct volume and peripheral blood lymphocyte DNA damage. Methods Sixty acute cerebral infarction patients were divided into small, medium and large infarct groups according to the infarct votume , 20 cases in each group. The percentage of DNA in the tail of lymphoeytic nuclear was assessed by single-cell gel electrophoresis (comet assay) in infarct groups and 20 normal controls (IMC group) , and the results were compared. Results In the alkaline comet assay, the percentage of DNA in the tail of lymphocytic nuclear in infarction groups were significantly higher than NC group (all P <0. 01) ; which in small and medium infarct groups were significantly lower than large infarct group (all P < 0. 01 ). In the neutral comet assay, the percentage of DNA DNA in the tail of lymphocytic nuclear in medium and large infarct groups were significantly higher than NC group (all P < 0. 01) ; which in large infarct group was significantly higher than small and medium infarct groups (all P < 0. 01 ). Conclusion Infarct volume may reflect the degree of peripheral lymphocytes DNA damage.%目的 探讨脑梗死体积与外周血淋巴细胞DNA损伤的关系.方法 按梗死灶体积将60例急性脑梗死患者分为小、中和大梗死组,每组 20例.应用单细胞凝胶电泳(彗星实验)检测各脑梗死组和20名正常对照者(正常对照组)外周血淋巴细胞核尾部DNA的百分比,并进行比较.结果 碱性彗星试验中,各脑梗死组的淋巴细胞核尾部DNA百分比显著高于正常对照组(均P<0.01);小、中梗死组淋巴细胞核尾部DNA百分比显著低于大梗死组(均P<0.01).中性彗星试验巾,中梗死组和大梗死组的淋巴细胞核尾部DNA百分比显著高于正常对照组(均P<0.01);大梗死组明显高于小、中梗死组(均P<0.01).结论 脑梗死体积可能可以反映外周血淋巴细胞DNA损伤程度.

  12. On genus expansion of superpolynomials

    OpenAIRE

    Mironov, Andrei; Morozov, Alexei; Sleptsov, Alexei; Smirnov, Andrey(ITEP, Moscow, 117218, Russia)

    2013-01-01

    Recently it was shown that the (Ooguri-Vafa) generating function of HOMFLY polynomials is the Hurwitz partition function, i.e. that the dependence of the HOMFLY polynomials on representation R is naturally captured by symmetric group characters (cut-and-join eigenvalues). The genus expansion and expansion through Vassiliev invariants explicitly demonstrate this phenomenon. In the present letter we claim that the superpolynomials are not functions of such a type: symmetric group characters do ...

  13. Warp drive with zero expansion

    CERN Document Server

    Natario, J

    2002-01-01

    It is commonly believed that Alcubierre's warp drive works by contracting space in front of the warp bubble and expanding the space behind it. We show that this contraction/expansion is but a marginal consequence of the choice made by Alcubierre and explicitly construct a similar spacetime where no contraction/expansion occurs. Global and optical properties of warp-drive spacetimes are also discussed.

  14. Warp drive with zero expansion

    International Nuclear Information System (INIS)

    It is commonly believed that Alcubierre's warp drive works by contracting space in front of the warp bubble and expanding the space behind it. We show that this contraction/expansion is but a marginal consequence of the choice made by Alcubierre and explicitly construct a similar spacetime where no contraction/expansion occurs. Global and optical properties of warp-drive spacetimes are also discussed

  15. Estimates of expansion time scales

    International Nuclear Information System (INIS)

    Monte Carlo simulations of the expansion of a spacefaring civilization show that descendants of that civilization should be found near virtually every useful star in the Galaxy in a time much less than the current age of the Galaxy. Only extreme assumptions about local population growth rates, emigration rates, or ship ranges can slow or halt an expansion. The apparent absence of extraterrestrials from the solar system suggests that no such civilization has arisen in the Galaxy. 1 figure

  16. Strategic Complexity and Global Expansion

    DEFF Research Database (Denmark)

    Oladottir, Asta Dis; Hobdari, Bersant; Papanastassiou, Marina;

    2012-01-01

    The purpose of this paper is to analyse the determinants of global expansion strategies of newcomer Multinational Corporations (MNCs) by focusing on Iceland, Israel and Ireland. We argue that newcomer MNCs from small open economies pursue complex global expansion strategies (CGES). We distinguish....... The empirical evidence suggests that newcomer MNCs move away from simplistic dualities in the formulation of their strategic choices towards more complex options as a means of maintaining and enhancing their global competitiveness....

  17. Blood vessel rupture by cavitation

    OpenAIRE

    Chen, Hong; Brayman, Andrew A.; Bailey, Michael R.; Matula, Thomas J.

    2010-01-01

    Cavitation is thought to be one mechanism for vessel rupture during shock wave lithotripsy treatment. However, just how cavitation induces vessel rupture remains unknown. In this work, a high-speed photomicrography system was set up to directly observe the dynamics of bubbles inside blood vessels in ex vivo rat mesenteries. Vascular rupture correlating to observed bubble dynamics were examined by imaging bubble extravasation and dye leakage. The high-speed images show that bubble expansion ca...

  18. Measuring Intracranial Pressure And Volume Noninvasively

    Science.gov (United States)

    Cantrell, John H.; Yost, William T.

    1994-01-01

    Ultrasonic technique eliminates need to drill into brain cavity. Intracranial dynamics instrument probes cranium ultrasonically to obtain data for determination of intracranial pressure (ICP) and pressure-volume index (PVI). Instrument determines sensitivity of skull to changes in pressure and by use of mechanical device to exert external calibrated pressure on skull. By monitoring volume of blood flowing into jugular vein, one determines change of volume of blood in cranial system. By measuring response of skull to increasing pressure (where pressure increased by tilting patient known amount) and by using cranial blood pressure, one determines intial pressure in cerebrospinal fluid. Once PVI determined, ICP determined.

  19. Donating Blood

    Science.gov (United States)

    ... And be sure to drink plenty of water, milk, or other liquids. Before donating, you'll need to answer some questions about your medical history, and have your temperature, pulse, blood pressure, and ...

  20. Blood smear

    Science.gov (United States)

    ... of RBCs due to body destroying them ( immune hemolytic anemia ) Low number of RBCs due to some red ... of Heinz bodies may indicate: Alpha thalassemia Congenital hemolytic anemia Disorder in which red blood cells break down ...

  1. Amylase - blood

    Science.gov (United States)

    Amylase is an enzyme that helps digest carbohydrates. It is made in the pancreas and the glands ... saliva. When the pancreas is diseased or inflamed, amylase releases into the blood. A test can be ...

  2. Moving blood.

    Science.gov (United States)

    Pelis, K

    1997-01-01

    Our internationally acclaimed journalist Sanguinia has returned safely from her historic assignment. Travelling from Homeric Greece to British Romanticism, she was witness to blood drinking, letting, bathing, and transfusion. In this report, she explores connections between the symbolic and the sadistic; the mythic and the medical--all in an effort to appreciate the layered meanings our culture has given to the movement of blood between our bodies. PMID:9407636

  3. 脂肪间充质干细胞对兔扩张皮肤血管增殖影响的实验研究%ADSCs transplantation promotes the blood vessels proliferation of expanded skin using a tissue expansion model

    Institute of Scientific and Technical Information of China (English)

    张泽敏; 姚永明; 阎贺; 吴彩风; 牛常英; 谭慎兴; 唐胜建; 杨彪炳

    2015-01-01

    Objective In the process of skin soft tissue expansion , the survival of the expanded skin flap depends on the number of new capillaries .Therefore, this study aimed to explore the effect of adipose derived stem cells on the number of newborn capillaries in skin tissue expansion . Methods 20 New Zealand rabbits were randomly divided into experiment group and control group(n=10).Adipose tissue was extracted from rabbit for isolation and culture of ADSCs in vitro , followed by flow cytometry and in-duced differentiation of epidermal cells .A 30ml expander was embedded in the back of the rabbits .Subcutaneous injection of lmL AD-SCs suspension was done on the rabbits of the experimental group , while the rabbits in control group were only injected with lmL isoton-ic saline.4 weeks later, after the completion of skin expansion , the tissue was extracted, followed by HE staining to observe the capil-lary number and immunohistochemical staining to examine the expression of vascular endothelial cell marker CD 31 and vascular endo-thelial growth factor ( VEGF) , and the statistic analysis of microvessel density .Elisa was used to detect VEGF expression in skin tis-sue. Results The results of HE staining showed there were more capillaries in experimental group than in control group . Immunohistochemical staining showed that the expression of CD 31 in the experimental group was increased and the microvessel density in the experimental group (10.70 ±1.89/area) was significantly higher than that in the control group(5.20 ±1.48/area) (P<0.05).Elisa results showed that the expression of VEGF increased in the experi-mental group([300.27 ±23.40]pg/mL) compared with the control group ([215.46 ±24.19]pg/mL) (P<0.05). Conclusion ADSCs can promote the angiogenesis in the expanded skin , thus increasing the blood supply and nutrition effect on expanded skin .%目的 在皮肤软组织扩张过程中,扩张皮瓣的成活很大程度取决于新生毛细血管的数量,文中探究

  4. Blood Clotting and Pregnancy

    Medline Plus

    Full Text Available ... Blood Basics Blood Disorders Anemia Bleeding Disorders Blood Cancers Blood Clots Blood Clotting and Pregnancy Clots and ... Increased maternal age Other medical illness (e.g., cancer, infection) back to top How are Blood Clots ...

  5. Biology of Blood

    Science.gov (United States)

    ... Mail Facebook TwitterTitle Google+ LinkedIn Home Blood Disorders Biology of Blood Overview of Blood Medical Dictionary Also ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  6. Blood (For Parents)

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy Blood KidsHealth > For Parents > Blood Print A A A ... about the mysterious, life-sustaining fluid called blood. Blood Basics Two types of blood vessels carry blood ...

  7. Blood Facts and Statistics

    Science.gov (United States)

    ... About Blood > Blood Facts and Statistics Printable Version Blood Facts and Statistics Facts about blood needs Facts ... about American Red Cross Blood Services Facts about blood needs Every two seconds someone in the U.S. ...

  8. Catecholamine blood test

    Science.gov (United States)

    Norepinephrine -- blood; Epinephrine -- blood; Adrenalin -- blood; Dopamine -- blood ... A blood sample is needed. ... the test. This is especially true if both blood and urine catecholamines are to be measured. You ...

  9. Expansion Nets and Expansion Processes of Elementary Net Systems

    Institute of Scientific and Technical Information of China (English)

    曹存根

    1995-01-01

    Occurrence nets are insufficient to precisely describe executions of elementary net systems with contacts.Traditionally,S-complementation is used for removal of contacts from the systems.Although the main behavior and properties of the original elementary net systems are preserved during S-complementation,their topologies may be changed greatly.This paper introduces a new kind of nets-expansion nets-for representing behavior of elementary net systems.As shown in the paper,expansion nets are natural as well as sufficient for describing the precise behavior of elementary net systems with or without contactks.

  10. Reed's Conjecture on hole expansions

    CERN Document Server

    Fouquet, Jean-Luc

    2012-01-01

    In 1998, Reed conjectured that for any graph $G$, $\\chi(G) \\leq \\lceil \\frac{\\omega(G) + \\Delta(G)+1}{2}\\rceil$, where $\\chi(G)$, $\\omega(G)$, and $\\Delta(G)$ respectively denote the chromatic number, the clique number and the maximum degree of $G$. In this paper, we study this conjecture for some {\\em expansions} of graphs, that is graphs obtained with the well known operation {\\em composition} of graphs. We prove that Reed's Conjecture holds for expansions of bipartite graphs, for expansions of odd holes where the minimum chromatic number of the components is even, when some component of the expansion has chromatic number 1 or when a component induces a bipartite graph. Moreover, Reed's Conjecture holds if all components have the same chromatic number, if the components have chromatic number at most 4 and when the odd hole has length 5. Finally, when $G$ is an odd hole expansion, we prove $\\chi(G)\\leq\\lceil\\frac{\\omega(G)+\\Delta(G)+1}{2}\\rceil+1$.

  11. On genus expansion of superpolynomials

    Energy Technology Data Exchange (ETDEWEB)

    Mironov, Andrei, E-mail: mironov@itep.ru [Lebedev Physics Institute, Moscow 119991 (Russian Federation); ITEP, Moscow 117218 (Russian Federation); National Research Nuclear University MEPhI, Moscow 115409 (Russian Federation); Morozov, Alexei, E-mail: morozov@itep.ru [ITEP, Moscow 117218 (Russian Federation); National Research Nuclear University MEPhI, Moscow 115409 (Russian Federation); Sleptsov, Alexei, E-mail: sleptsov@itep.ru [ITEP, Moscow 117218 (Russian Federation); Laboratory of Quantum Topology, Chelyabinsk State University, Chelyabinsk 454001 (Russian Federation); KdVI, University of Amsterdam (Netherlands); Smirnov, Andrey, E-mail: asmirnov@math.columbia.edu [ITEP, Moscow 117218 (Russian Federation); Columbia University, Department of Mathematics, New York (United States)

    2014-12-15

    Recently it was shown that the (Ooguri–Vafa) generating function of HOMFLY polynomials is the Hurwitz partition function, i.e. that the dependence of the HOMFLY polynomials on representation R is naturally captured by symmetric group characters (cut-and-join eigenvalues). The genus expansion and expansion through Vassiliev invariants explicitly demonstrate this phenomenon. In the present paper we claim that the superpolynomials are not functions of such a type: symmetric group characters do not provide an adequate linear basis for their expansions. Deformation to superpolynomials is, however, straightforward in the multiplicative basis: the Casimir operators are β-deformed to Hamiltonians of the Calogero–Moser–Sutherland system. Applying this trick to the genus and Vassiliev expansions, we observe that the deformation is fully straightforward only for the thin knots. Beyond the family of thin knots additional algebraically independent terms appear in the Vassiliev and genus expansions. This can suggest that the superpolynomials do in fact contain more information about knots than the colored HOMFLY and Kauffman polynomials. However, even for the thin knots the beta-deformation is non-innocent: already in the simplest examples it seems inconsistent with the positivity of colored superpolynomials in non-(anti)symmetric representations, which also happens in I. Cherednik's (DAHA-based) approach to the torus knots.

  12. On genus expansion of superpolynomials

    International Nuclear Information System (INIS)

    Recently it was shown that the (Ooguri–Vafa) generating function of HOMFLY polynomials is the Hurwitz partition function, i.e. that the dependence of the HOMFLY polynomials on representation R is naturally captured by symmetric group characters (cut-and-join eigenvalues). The genus expansion and expansion through Vassiliev invariants explicitly demonstrate this phenomenon. In the present paper we claim that the superpolynomials are not functions of such a type: symmetric group characters do not provide an adequate linear basis for their expansions. Deformation to superpolynomials is, however, straightforward in the multiplicative basis: the Casimir operators are β-deformed to Hamiltonians of the Calogero–Moser–Sutherland system. Applying this trick to the genus and Vassiliev expansions, we observe that the deformation is fully straightforward only for the thin knots. Beyond the family of thin knots additional algebraically independent terms appear in the Vassiliev and genus expansions. This can suggest that the superpolynomials do in fact contain more information about knots than the colored HOMFLY and Kauffman polynomials. However, even for the thin knots the beta-deformation is non-innocent: already in the simplest examples it seems inconsistent with the positivity of colored superpolynomials in non-(anti)symmetric representations, which also happens in I. Cherednik's (DAHA-based) approach to the torus knots

  13. Thermal expansion studies of carbon nanotube-reinforced silver nanocomposite

    International Nuclear Information System (INIS)

    In the present study, a simple and highly effective physical mixing method was used to synthesise carbon nanotube (CNT)-reinforced silver nanocomposites. Composites were prepared with different contents (vol%) of functionalised multiwall nanotubes. The microstructure of synthesised nanocomposites was analysed by X-ray diffraction, electron diffraction spectroscopy, and scanning electron microscopy. Microstructural characterisations revealed good distribution of nanotubes in the silver matrix. The thermal expansion behaviour of the composites was studied in reference to the variation in nanotube volume content in the silver matrix. It was observed that the coefficient of thermal expansion decreased with the increase in the percentage of CNT volume. The thermal expansion of the CNT-reinforced silver composites decreased to 55 % of pure silver upon the introduction of 6 vol% of nanotubes into the silver matrix. The thermal expansion behaviour of the CNT-reinforced silver composites was also analysed theoretically using the rule of mixture and Schapery's model. The CNT-reinforced silver composites may be a promising contact and thermal management material in electronic devices.

  14. Regulation of gas infrastructure expansion

    International Nuclear Information System (INIS)

    The topic of this dissertation is the regulation of gas infrastructure expansion in the European Union (EU). While the gas market has been liberalised, the gas infrastructure has largely remained in the regulated domain. However, not necessarily all gas infrastructure facilities - such as gas storage facilities, LNG import terminals and certain gas transmission pipelines - need to be regulated, as there may be scope for competition. In practice, the choice of regulation of gas infrastructure expansion varies among different types of gas infrastructure facilities and across EU Member States. Based on a review of economic literature and on a series of in-depth case studies, this study explains these differences in choices of regulation from differences in policy objectives, differences in local circumstances and differences in the intrinsic characteristics of the infrastructure projects. An important conclusion is that there is potential for a larger role for competition in gas infrastructure expansion.

  15. Thermal Expansion of Hafnium Carbide

    Science.gov (United States)

    Grisaffe, Salvatore J.

    1960-01-01

    Since hafnium carbide (HfC) has a melting point of 7029 deg. F, it may have many high-temperature applications. A literature search uncovered very little information about the properties of HfC, and so a program was initiated at the Lewis Research Center to determine some of the physical properties of this material. This note presents the results of the thermal expansion investigation. The thermal-expansion measurements were made with a Gaertner dilatation interferometer calibrated to an accuracy of +/- 1 deg. F. This device indicates expansion by the movement of fringes produced by the cancellation and reinforcement of fixed wave-length light rays which are reflected from the surfaces of two parallel quartz glass disks. The test specimens which separate these disks are three small cones, each approximately 0.20 in. high.

  16. Automatic blood pressure measuring system (M091)

    Science.gov (United States)

    1977-01-01

    The Leg Volume Measuring System is used to measure leg calf girth changes that occur during exposure to lower body negative pressure as a result of pooling of blood and other fluids in the lower extremities.

  17. On the large $N$ expansion in hyperbolic sigma-models

    CERN Document Server

    Niedermaier, Max

    2007-01-01

    Invariant correlation functions for ${\\rm SO}(1,N)$ hyperbolic sigma-models are investigated. The existence of a large $N$ asymptotic expansion is proven on finite lattices of dimension $d \\geq 2$. The unique saddle point configuration is characterized by a negative gap vanishing at least like 1/V with the volume. Technical difficulties compared to the compact case are bypassed using horospherical coordinates and the matrix-tree theorem.

  18. Shengli Making New Progress in Expansion at Overseas Markets

    Institute of Scientific and Technical Information of China (English)

    Yu Ankun

    2001-01-01

    @@ Aiming at its established strategic goal for international operation, Shengli Oilfields made new progress last year in expansion at overseas markets and cooperation with foreign firms. In the fields of contracting projects and providing labor services on the international oil/gas exploration and development market, it has embarked on a higher level of starting point with respect to number of projects,value of investment and volume of engineering.

  19. Erythropoietin reduces storage lesions and decreases apoptosis indices in blood bank red blood cells

    OpenAIRE

    Oscar Andrés Penuela; Fernando Palomino; Lina Andrea Gómez

    2015-01-01

    ABSTRACT Background: Recent evidence shows a selective destruction of the youngest circulating red blood cells (neocytolysis) trigged by a drop in erythropoietin levels. Objective: The aim of this study was to evaluate the effect of recombinant human erythropoietin beta on the red blood cell storage lesion and apoptosis indices under blood bank conditions. Methods: Each one of ten red blood cell units preserved in additive solution 5 was divided in two volumes of 100 mL and assigned to one...

  20. Effect of plasma exchange on blood viscosity and cerebral blood flow.

    OpenAIRE

    Brown, M M; Marshall, J

    1982-01-01

    The effects of plasma exchange using a low viscosity plasma substitute on blood viscosity and cerebral blood flow were investigated in eight subjects with normal cerebral vasculature. Plasma exchange resulted in significant reductions in plasma viscosity, whole blood viscosity, globulin and fibrinogen concentration without affecting packed cell volume. The reduction in whole blood viscosity was more pronounced at low shear rates suggesting an additional effect on red cell aggregation. Despite...