Antioxidant and antihemolytic activities of methanol extract of Hyssopus angustifolius

This study was designed to evaluate antioxidant and antihemolytic activities of Hyssopus angustifolius flower, stem and leaf methanol extracts by employing various in vitro assays. The leaf extract showed the best activity in DPPH (63.2 ± 2.3 μg mL-1) and H2O2  (55.6 ± 2.6 μg mL-1) models compared to the other extracts. However, flower extract exhibited the highest Fe2+ chelating activity (131.4 ± 4.4 μg mL-1). The extracts exhibited good antioxidant activity in linoleic acid peroxidation and reducing power assays, but were not comparable to vitamin C. The stem (23.58 ± 0.7 μg mL-1) and leaf (26.21 ± 1 μg mL-1) extracts showed highest level of antihemolytic activity than the flower extract

Antidepressant and antioxidant activities of Artemisia absinthium L. at flowering stage

Artemisia absinthium (Asteraceae) is widely used in Iranian traditional medicine. Its effects may be correlated with the presence of antioxidant compounds. Methanolic extract of A. absinthium aerial part at flowering stage was screened for antioxidant activities by five complementary test systems. Also, its antidepressant activity was determined by forced swimming (FST) and tail suspension tests (TST). The extract showed good antioxidant activity. Also, the extract showed good reducing power activitybetween 50 and 800 ìgml-1. The extract exhibited a good activity in H2O2 scavenging (IC50 = 243 ± 12.15 ìg ml-1). IC50 for iron ion chelating activity was 419 ± 20.95 ìg ml-1. Quercetin, BHA, EDTA and ascorbicacid used as positive controls in parallel experiments. The extract showed high phenolic and flavonoid contents. Extract showed good antidepressant activity in FST. The extract shortened remarkably the immobility period during the FST and TST and exhibited a dose dependent activity. All test groups were significantly different form control group (P 0.05) in TST. LD50 was 3700 mg/kg. These results introduced A. absinthium aerial parts as an easily accessible and edible source of natural antioxidants and antidepressant

Biological and pharmacological effects of Delphinium elbursense

Antidepressant, antihypoxic and antioxidant activities of aerial parts of Delphinium elbursense were investigated employing nine various assay systems. Antidepessant activity was examined by using forced swimming test and tail suspension test in mice. The extracts at all tested doses show significant activity as compared to control group. Antihypoxic activity was investigated in two models, haemic and circulatory. The effects were pronounced and dose-dependent in both model of hypoxia. Extracts showed weak antioxidant activity in some models. IC50 for 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical-scavenging activity was 116.2 ± 5.6 mg ml-1. Extracts showed nitric oxide-scavenging activity between 0.1 and 1.6 mg ml-1 (IC50 = 502.3 ± 18 mg ml-1) and a very weak Fe2+ chelating ability (IC50 = 1.01 ± 0.03 mg ml-1). It also exhibited low antioxidant activity in hemoglobin-induced peroxidation of linoleic acid but was capable of scavenging hydrogen peroxide in a concentration dependent manner. Extract show antihemolytic activity againts hydrogen peroxide (H2O2) induced hemolysis (558.7 ± 31 mg ml-1). The total phenolic compounds in extract were determined as gallic acid equivalents (52.24 ± 1.7) and total flavonoid contents were calculated as quercetin equivalents (17.26 ± 0.6) from a calibration curve.Keywords: Antidepressant, antihypoxic, Delphinium elbursense, flavonoid contents, forced swimming test, medicinal plants, phenolic contents, tail suspension testAfrican Journal of Biotechnology Vol. 9(34), pp. 5542-5549, 23 August, 201

On the acoustic levitation stability behaviour of spherical and ellipsoidal particles

We present here an in-depth analysis of particle levitation stability and the role of the radial and axial forces exerted on fixed spherical and ellipsoidal particles levitated in an axisymmetric acoustic levitator, over a wide range of particle sizes and surrounding medium viscosities. We show that the stability behaviour of a levitated particle in an axisymmetric levitator is unequivocally connected to the radial forces: the loss of levitation stability is always due to the change of the radial force sign from positive to negative. It is found that the axial force exerted on a sphere of radius ${R}_{s}$ increases with increasing viscosity for ${R}_{s} / \lambda \lt 0. 0125$ ( $\lambda$ is the acoustic wavelength), with the viscous contribution of this force scaling with the inverse of the sphere radius. The axial force decreases with increasing viscosity for spheres with ${R}_{s} / \lambda \gt 0. 0125$ . The radial force, on the other hand, decreases monotonically with increasing viscosity. The radial and axial forces exerted on an ellipsoidal particle are larger than those exerted on a volume-equivalent sphere, up to the point where the ellipsoid starts to act as an obstacle to the formation of the standing wave in the levitator chambe

Some conditions implying normality of operators

Let $T\in\mathbb{B}(\mathscr{H})$ and $T=U|T|$ be its polar decomposition. We proved that (i) if $T$ is log-hyponormal or $p$-hyponormal and $U^n=U^\ast$ for some $n$, then $T$ is normal; (ii) if the spectrum of $U$ is contained in some open semicircle, then $T$ is normal if and only if so is its Aluthge transform $\widetilde{T}=|T|^{1\over2}U|T|^{1\over2}$

The use of embolic signal detection in multicenter trials to evaluate antiplatelet efficacy: signal analysis and quality control mechanisms in the CARESS (Clopidogrel and Aspirin for Reduction of Emboli in Symptomatic carotid Stenosis) trial

<p><b>Background and Purpose:</b> The CARESS (Clopidogrel and Aspirin for Reduction of Emboli in Symptomatic carotid Stenosis) trial proved the effectiveness of the combination of clopidogrel and aspirin compared with aspirin alone in reducing presence and number of microembolic signals (MES) in patients with recently symptomatic carotid stenosis. The present study aimed at installing primary and secondary quality control measures in CARESS because MES evaluation relies on subjective judgment by human experts.</p> <p><b>Methods:</b> As primary quality control, centers participating in CARESS evaluated a reference digital audio tape (DAT) before the study containing both MES and artifacts. Interobserver agreement of classifying signals as MES was expressed as proportions of specific agreement of positive ratings (ps±values). For all DATs included in CARESS (n=300), online number of MES and off-line number of MES read by the central reader were compared using correlation coefficients. As secondary control, a sample of 16 of 300 DATs was cross-validated by another independent reader (post-trial validator).</p> <p><b>Results:</b> For the reference tape, the cumulative ps±value was 0.894 based on 12 of 14 observers. Two observers with very different results improved after a training procedure. Agreement between post-trial validator and central reader was ps+=0.805, indicating very good agreement. Correlation between online evaluation and off-line evaluation of DATs was very good overall (cumulative ρ=0.84; P<0.001).</p> <p><b>Conclusion:</b> Multicenter studies using MES as outcome parameter are feasible. However, primary and secondary quality control procedures are important.</p&gt

The relation between environmental parameters of Hormuzgan coastline in Persian Gulf and occurrence of the first harmful algal bloom of Cochlodinium polykrikoides (Gymnodiniaceae)

Cochlodinium polykrikoides was bloomed in the Persian Gulf for the first time in September 2008, started from the Strait of Hormuz and then spread out towards the northern parts covering most of the areas of the Gulf and lasted 8 months. In order to find out environmental conditions during the bloom, a monthly sampling program was carried out in seven surface stations in 2008-2009. At each station, three samples (triplicates) were collected for phytoplankton analysis and also one sample for environmental analyses, including salinity, chlorophyll a and nutrients. Blooms of C. polykrikoides were observed with a seawater temperature of 20.1 to 31.0 °C, salinity 37.0-40.1 ppt and nutrient concentration ranges during the bloom and red tide were 0.064-0.707 mg/l nitrate + nitrite and 0.001-1.66 mg/l phosphate, respectively. Maximum of C. polykrikoides abundance was measured 26 × 106 cells L-1 in October 2008. Kruscal wallis test demonstrated a significant difference in densities and chlorophyll-a in different months and seasons not in different stations. This study showed increase of temperature (>31.0 °C) stopped bloom and red tide due to C. polykrikoides in both the eastern and middle sampling stations but in the western stations was determined decrease in nutrient amounts as the major factor therefore increased nutrient of coastal waters, and environmental conditions could have efficacy the occurrence of this dinoflagellate