			Home About us Contact

Fraction Decreased (fraction + decreased)

Distribution by Scientific Domains

Medical Sciences	60%
Earth and Environmental Science	20%

Selected Abstracts

Effects of Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy on Doppler Tei Index: A Midterm Follow-Up

ECHOCARDIOGRAPHY, Issue 2 2005
F.E.S.C., Josef Veselka M.D., Ph.D.
Alcohol septal ablation (PTSMA) improves outflow gradient, left ventricular (LV) diastolic function, and symptoms in patients with hypertrophic obstructive cardiomyopathy (HOCM). Tei index (TI) is a Doppler parameter reflecting both systolic and diastolic LV function. Midterm changes of TI after PTSMA have not been determined up to now. Twenty-seven consecutive patients (mean age 53 ± 13 years) with symptomatic HOCM underwent PTSMA procedure. Clinical and echocardiographic data were collected at baseline, 6 and 12 months after PTSMA. TI decreased from 0.67 ± 0.11 to 0.55 ± 0.06, isovolumic contractile time (ICT) decreased from 74 ± 20 to 48 ± 11 ms, isovolumic relaxation time decreased from 146 ± 25 to 117 ± 9 ms, and LV ejection time decreased from 330 ± 42 to 298 ± 13 ms. LV remodeling was determined by LV dimension increase from 46 ± 6 to 48 ± 6 mm and basal septum thickness reduction from 22 ± 4 to 15 ± 3 mm. LV ejection fraction decreased from 78 ± 7 to 73 ± 6% and maximal outflow gradient decreased from 69 ± 44 to 15 ± 11 mmHg. All changes were statistically significant (P < 0.01). Symptomatic improvement was characterized by relief of dyspnea (2.5 ± 0.7 versus 1.4 ± 0.6 NYHA class; P < 0.01) and angina pectoris (2.6 ± 0.9 versus 0.7 ± 0.7 CCS class; P < 0.01). PTSMA is an effective method of therapy for HOCM. Shortening of TI suggests the improvement of LV myocardial performance in the midterm follow-up. [source]

Estrogenic effect of leachates and soil extracts from lysimeters spiked with sewage sludge and reference endocrine disrupters

ENVIRONMENTAL TOXICOLOGY, Issue 2 2002
Halim Dizer
Abstract Several experiments were conducted to evaluate the behavior and performance of some potential endocrine disrupters (ECDs). Two in vitro screening assays, one based on MCF7-cell proliferation (E-screen test) and the other on estrogenic receptor activity [enzyme-linked receptor assay (ELRA)], were used for the tests, which were done in lysimeters 80 cm in diameter with depths of 30 cm (shallow) or 90 cm (deep). A sandy soil was used to fill in all lysimeters, which were spiked on the surface with either: (a) a sewage sludge (SS) at a dose equivalent to 20 tons ha,1; (b) a mixture of reference ECDs, comprising 17,- and 17,-estradiol (E2), nonylphenol, octylphenol, and bisphenol A at doses 100 times higher than the maximum concentrations respectively found in the applied SS; or (c) a mixture of ECDs and SS. After percolation of the lysimeters with rain and/or artificial water, five leachates were sampled from each lysimeter during a period of 210 days. Immediately after the lysimeter percolation experiments, four and six soil fractions were dissected from, respectively, the 30-cm and 90-cm lysimeters and extracted by water. Both the leachate and soil extract samples were analyzed for their estrogenicity using the assays indicated above. The E-screen assay was highly sensitive only for some leachate and extract samples but gave no response for most leachates and soil extracts. The results of the ELRA assay suggests a significantly higher estrogenicity of leachate samples from shallow lysimeters compared with that of leachates from deep lysimeters. In contrast, the estrogenic effect measured for soil extracts of shallow lysimeters was lower than that measured for soil extracts of deep lysimeters. The results of the E-screen assay suggests the occurrence of a fast mobilization of applied ECDs and a moderate retardation effect of native ECDs contained in applied SS in the sandy soil used in the lysimeters. In lysimeters spiked with a mixture of SS and ECDs, the washing-out effect of ECDs in the first leachate fraction decreased, but the distribution of ECDs in the lysimeters increased. The relatively high estrogenic impact measured for soil water extracts suggests that the ECDs were mostly associated with water-soluble fractions of organic matter and/or water-suspended fractions of the mineral soil matrix. The application of SS to agricultural and forest fields may determine the immobilization of ECDs in soil or their movement to surface and/or groundwater. Therefore, an endocrine risk of exposure exists for the water and soil organisms. © 2002 Wiley Periodicals, Inc. Environ Toxicol 17: 105,112, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.10038 [source]

Subcellular cadmium distribution, accumulation, and toxicity in a predatory gastropod, Thais clavigera, fed different prey

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2006
Ma-Shan Cheung
Abstract Bioaccumulation and toxicity of Cd were investigated in a marine predatory whelk, Thais clavigera, after being fed with the rock oyster, Saccostrea cucullata, or the herbivorous snail, Monodonta labio, for up to four weeks. The oysters and snails had different subcellular Cd distributions and concentrations in their bodies given their different metal-handling strategies and were exposed to dissolved Cd for two weeks before being fed to the whelks. After four weeks of dietary exposure, the Cd body concentrations in T. clavigera increased from 3.1 ,g/g to between 22.9 and 41.8 ,g/g and to between 22.7 and 24.1 ,g/g when they were fed with oyster and snail prey, respectively. An increasing proportion of Cd was found to be distributed in the metallothionein (MT)-like proteins and organelle fractions, whereas the relative distribution in the metal-rich granules fraction decreased when the whelks were fed Cd-exposed prey. At the highest Cd dosage, more Cd was distributed in the pool of metal-rich granules when the whelks were fed the oysters than when they were fed the snails. Among all the biomarkers measured (MT induction, condition index, lipid peroxidation, and total energy reserve including carbohydrate, lipid, and protein), only MT showed a significant difference from the control treatments, and MT was the most sensitive biomarker for dietary Cd exposure. No toxicity was found in the whelks fed different Cd-exposed prey as revealed by various biomarkers at the different biological levels. Our results imply that metal fractionation in prey can alter the subsequent subcellular metal distribution in predators and that dietary Cd toxicity to the whelks was low, even when the accumulated Cd body concentrations were high. [source]

Effects of Interactions of Moisture Regime and Nutrient Addition on Nodulation and Carbon Partitioning in Two Cultivars of Bean (Phaseolus vulgaris L.)

JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2001
T. Boutraa
Major limitations of bean (Phaseolus vulgaris L.) production in arid and semiarid regions are lack of moisture and low soil fertility. An experiment was conducted to determine the effects of soil moisture and N : P : K (20 : 10 : 10) fertilizer on root and shoot growth of two cultivars of bean: cv. Carioca, an indeterminate Brazilian landrace, and cv. Prince, a determinate cultivar grown in Europe. Carioca appears generally stress-tolerant while Prince is intolerant. Seedlings were grown in pots of non-sterile soil at 30, 60 or 90 % field capacity (FC), and given 0, 0.1 or 1 g (kg soil),1 of compound fertilizer. The soil contained a population of effective Rhizobium. Growth of both cultivars was greatest in the high moisture and high nutrient treatments. Root fractions were highest at low nutrient supply; the effect of water was not significant. Leaf fraction decreased as root fraction increased. Numbers of nodules were highest at high and intermediate moisture when no fertilizer was applied. Numbers were lowest at 30 % FC and at the highest fertilizer rate. Masses of nodules and fractions followed the same pattern. Decreasing water regime reduced the relative growth rate (RGR) of Prince, while Carioca maintained high RGR at unfavourable conditions of water and nutrients. Net assimilation rates (NAR) were unaffected by nutrient addition, and reduced by low moisture regime. Water use efficiencies (WUEs) were reduced by water stress but increased by nutrient deficiency. The water utilization for dry matter production was optimal at 60 % FC. Einflüsse der Interaktionen von Bodendenfeuchte und Düngung auf die Knöllchenbildung und Kohlenstoff verteilung bei zwei Bohnenkultivaren (Phaseolus vulgaris L.) Der begrenzende Hauptfaktor der Bohnenproduktion in ariden und semiariden Regionen sind der Feuchtigkeitsmangel und die Bodenfruchbarkeit. Es wurde ein Experiment durchgeführt, um die Wirkungen des Bodenwassers und von N : P : K (20 : 10 : 10) Dünger auf das Wurzel- und Sproßwachstum an zwei Kultivaren von Bohnen (Phaseolus vulgaris L. cv. Carioca, eine brasilianischen, indeterminierte Landsorte und cv. Prince, eine determinierter in Europa angebauter Kultivar) zu untersuchen. Carioca erscheint grundsätzlich streßtoleranter im Vergleich zu Prince. Die Sämlinge wurden in Gefäßen mit nichtsterilisiertem Boden unter Feldkapazitäten von 30,60 oder 90 % mit 0, 0,1 oder 1 g eines Volldüngers angezogen. Der Boden enthielt eine Population von wirksamem Rhizobium. Das stärkste Wachstum wurde bei beiden Kultivaren unter dem Einfluß des höchsten Feuchtigkeitsgehaltes und der höchsten Düngermenge gefunden. Der Wurzelanteil war bei der geringen Düngermenge am niedrigsten. Der Einfluß der Bodenfeuchtigkeit war nicht signifikant. Der Blattanteil nahm mit zunehmendem Wurzelanteil ab. Die Anzahl der Knötchen war bei hoher und mittlerer Bodenfeuchte und ohne Düngeranwendung am höchsten. Die Anzahl war am geringsten bei 30 % FC und der höchsten Düngermenge. Die Knötchenmasse und ihr Anteil reagierte entsprechend. Abnehmende Bodenfeuchte reduzierte die relative Wachtumsrate (RGR) von Prince, während Carioca einen hohen RGR auch bei ungünstigen Bedingungen bezüglich Wasser und Düngung behielt. Die Nettoassimilationsraten wurden durch die Düngung nicht beeinflußt; sie gingen bei geringer Bodenfeuchte zurück. Die Wassernutzungseffiziens (WUE) wurde bei Wasserstreß reduziert, nahm aber bei Düngermangel zu. Die Wassernutzung für die Trockenmasseproduktion war bei 60 % Feldkapazität am höchsten. [source]

Experimental and numerical research for fluidization behaviors in a gas,solid acoustic fluidized bed

AICHE JOURNAL, Issue 7 2010
Changqing Cao
Abstract The effects of sound assistance on fluidization behaviors were systematically investigated in a gas,solid acoustic fluidized bed. A model modified from Syamlal,O'Brien drag model was established. The original solid momentum equation was developed and an acoustic model was also proposed. The radial particle volume fraction, axial root-mean-square of bed pressure drop, granular temperature, and particle velocity in gas,solid acoustic fluidized bed were simulated using computational fluid dynamics (CFD) code Fluent 6.2. The results showed that radial particle volume fraction increased using modified drag model compared with that using the original one. Radial particle volume fraction was revealed as a parabolic concentration profile. Axial particle volume fraction decreased with the increasing bed height. The granular temperature increased with increasing sound pressure level. It showed that simulation values using CFD code Fluent 6.2 were in agreement with the experimental data. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source]

Characterization of the Acute Cardiac Electrophysiologic Effects of Ethanol in Dogs

ALCOHOLISM, Issue 9 2007
Guilherme Fenelon
Background: Alcohol has been related to atrial fibrillation (holiday heart syndrome), but its electrophysiologic actions remain unclear. Methods: We evaluated the effects of alcohol in 23 anesthetized dogs at baseline and after 2 cumulative intravenous doses of ethanol: first dose 1.5 ml/kg (plasma level 200 mg/dl); second dose 1.0 ml/kg (279 mg/dl). In 13 closed-chest dogs (5 with intact autonomic nervous system, 5 under combined autonomic blockade and 3 sham controls), electrophysiologic evaluation and monophasic action potential (MAP) recordings were undertaken in the right atrium and ventricle. In 5 additional dogs, open-chest biatrial epicardial mapping with 8 bipoles on Bachmann's bundle was undertaken. In the remaining 5 dogs, 2D echocardiograms and ultrastructural analysis were performed. Results: In closed-chest dogs with intact autonomic nervous system, ethanol had no effects on surface electrocardiogram and intracardiac variables. At a cycle length of 300 milliseconds, no effects were noted on atrial and ventricular refractoriness and on the right atrial MAP. These results were not altered by autonomic blockade. No changes occurred in sham controls. In open-chest dogs, ethanol did not affect inter-atrial conduction time, conduction velocity, and wavelength. Atrial arrhythmias were not induced in any dog, either at baseline or after ethanol. Histological and ultrastructural findings were normal but left ventricular (LV) ejection fraction decreased in treated dogs (77 vs. 73 vs. 66%; p = 0.04). Conclusion: Ethanol at medium and high doses depresses LV systolic function but has no effects on atrial electrophysiological parameters. These findings suggest that acute alcoholic intoxication does not directly promote atrial arrhythmias. [source]

Nonstationary disposition of valproic acid during prolonged intravenous infusion: contributions of unbound clearance and protein binding

BIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 6 2001
Tori L. Arens
Abstract Circadian variations in disposition have been observed for a variety of agents, including anticonvulsants. Valproic acid (VPA), an anticonvulsant used to control generalized and partial seizures, has exhibited diurnal oscillations in steady-state concentrations during long-term administration to humans and non-human primates. The present study was conducted to assess potential diurnal changes in the disposition of VPA during prolonged i.v. infusion in rats. Animals, maintained on a strict 12-h per day light cycle, were equipped with venous cannulae and an arterial microdialysis probe. VPA was administered as a 50-mg/kg loading dose followed by a 42 mg/kg/h infusion for 70 h. Blood and microdialysate samples were obtained at timed intervals after establishment of steady-state throughout two complete light/dark cycles; and total (serum) and unbound (microdialysate) VPA was determined by gas chromatography. Modest oscillations (6,7 h period) in total and unbound VPA were observed; clearance and binding parameters were not different between light and dark periods. However, unbound clearance increased, and unbound fraction decreased, with time over the course of the infusion. These results suggest that time-dependent changes in VPA disposition occur in rats, although oscillations in steady-state concentrations do not appear to be diurnal in nature. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Phenotyping the Right Ventricle in Patients with Pulmonary Hypertension

CLINICAL AND TRANSLATIONAL SCIENCE, Issue 4 2009
M.S., Marc A. Simon M.D.
Abstract Right ventricular (RV) failure is associated with poor outcomes in pulmonary hypertension (PH). We sought to phenotype the RV in PH patients with compensated and decompensated RV function by quantifying regional and global RV structural and functional changes. Twenty-two patients (age 51 ± 11, 14 females, mean pulmonary artery (PA) pressure range 13,79 mmHg) underwent right heart catheterization, echocardiography, and ECG-gated multislice computed tomography of the chest. Patients were divided into three groups: Normal, PH with hemodynamically compensated, and decompensated RV function (PH-C and PH-D, respectively). RV wall thickness (WT) was measured at end-diastole (ED) and end-systole (ES) in three regions: infundibulum, lateral free wall, and inferior free wall. Globally, RV volumes progressively increased from Normal to PH-C to PH-D and RV ejection fraction decreased. Regionally, WT increased and fractional wall thickening (FWT) decreased in a spatially heterogeneous manner. Infundibular wall stress was elevated and FWT was lower regardless of the status of global RV function. In PH, there are significant phenotypic abnormalities in the RV even in the absence of overt hemodynamic RV decompensation. Regional changes in RV structure and function may be early markers of patients at risk for developing RV failure. [source]

Scintigraphic evaluation of intrapulmonary shunt in normoxemic cirrhotic patients and effects of terlipressin

HEPATOLOGY RESEARCH, Issue 10 2010
George Kalambokis
Aim:, The magnitude of intrapulmonary shunt (IPS) in cirrhotic patients without hypoxemia remains undefined. We evaluated the severity and clinical correlations of IPS in normoxemic cirrhotics, and possible IPS alterations after terlipressin treatment. Methods:, Fifteen patients with alcoholic cirrhosis without hypoxemia were studied at baseline and after the administration of 2 mg of terlipressin. The IPS fraction was evaluated by lung perfusion scan after the i.v. injection of technetium-99m -labeled macroaggregated albumin (99mTc-MAA) and calculation of brain uptake (positive value ,6%). Cardiac output (CO), pulmonary artery systolic pressure (PASP) and pulmonary vascular resistance (PVR) were evaluated by Doppler echocardiography. Mean arterial pressure (MAP) was measured and the ratio MAP/CO was calculated as an index of systemic vascular resistance (SVR). Portal vein velocity (PVV) and portal venous flow (PVF) were also assessed by Doppler ultrasonography. Results:, Three patients (20%) had an IPS fraction of more than 6%. A significant inverse correlation with platelet count (P = 0.001) and a direct correlation with Child,Pugh score (P = 0.06), PVV (P = 0.07) and PVF (P = 0.07) were noted. IPS fractions decreased significantly after terlipressin administration (P = 0.00001); the IPS fraction fell below 6% in all three patients with positive baseline values. Terlipressin treatment induced a significant decrease in CO (P = 0.003) and significant increases in MAP (P = 0.0003), SVR (P = 0.0003), SPAP (P = 0.001) and PVR (P = 0.01). Conclusion:, IPS fractions detected by 99mTc-MAA lung scan were inversely correlated with platelet count and directly with liver disease severity, and found abnormal in 20% of normoxemic cirrhotic patients. Terlipressin reduced significantly the magnitude of the shunt. [source]

The circulating IGF system and its relationship with 24-h glucose regulation and insulin sensitivity in healthy subjects

CLINICAL ENDOCRINOLOGY, Issue 6 2003
Jan Frystyk
Summary objective and design It has been suggested that circulating free IGF-I participates in glucose homeostasis and that IGFBP-1 reflects changes in insulin sensitivity. To study this further, we examined 10 healthy, nonobese subjects under standardized conditions for 24 h with and without an intravenous infusion of glucose, the latter in order to augment insulin sensitivity. Serum was collected every 2 h for analysis of free and total IGFs, IGFBP-1, , 2 and , 3 and the acid labile subunit (ALS). Insulin sensitivity was estimated at the end of each 24-h study period by use of the hyperinsulinaemic euglycaemic clamp technique. results Glucose infusion resulted in mild hyperglycaemia (P < 0·0001), a reduction in IGFBP-1 by approximately 40% (P < 0·0003), and increased insulin and C-peptide levels (P < 0·0001). Glucose infusion also increased insulin sensitivity (P < 0·003). However, despite the reduction in IGFBP-1, glucose infusion did not increase free IGF-I over the control level, and free IGF-II was slightly reduced (P < 0·02). Irrespective of glucose infusion, free IGF-I and -II remained stable during daytime (i.e. they were unresponsive to meal-related changes in plasma glucose), but both free fractions decreased during the night, reaching nadir at 04·00 h. None of the other members of the IGF system showed any relationship with plasma glucose levels. Finally, we failed to observe any relationship between changes in insulin sensitivity and the circulating IGF system. conclusion We found no evidence that the circulating IGF system is involved in meal-related blood glucose regulation or that it reflects short-term changes in insulin sensitivity in healthy, nonobese subjects. However, we cannot preclude that the observed changes in circulating IGFBP-1 may affect the glucose-lowering effect of IGF-I and -II at the local tissue level. [source]