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Introduction Asthma is one of the most common chronic inflammatory diseases, and is ranked among the top 10 prevalent conditions. It affects about 300 million people worldwide and is projected [...], The subacute use of corticosteroids has side-effects such as glucose intolerance, dyslipidemia, anxiety, and depression, which could be halted with vitamin D, which is an immunomodulatory vitamin. Thus, we aimed to study the anti-asthmatic efficacy and side-effects profile of vitamin D, the corticosteroid dexamethasone, and their combination on ovalbumin-induced airway inflammation in rats. For this, 2 different doses of vitamin D (50 IU/kg, daily for 2 weeks, or and 60000 IU/kg, bolus dose, by intraperitoneal injection (i.p.)) were administered in combination with dexamethasone (2.5 mg/kg, i.p., for 2 weeks) prior to challenge with ovalbumin. At the end of the therapy, the asthmatic parameters such as differential white blood cell counts, serum levels of immunoglobulin E, bronchoalveolar lavaged fluid, and interleukin-5, as well as serum levels of nitric oxide were significantly increased after allergen challenges in asthmatic rats as compared with the controls. Such increases were significantly attenuated by monotherapy with vitamin D and with combination therapy of vitamin D and dexamethasone, where the combination therapy was superior to the monotherapy. Dexamethasone-induced hyperglycemia, hyperlipidemia, and behavioral abnormalities in the allergic rats were attenuated with vitamin D. The daily dose was better for controlling serum levels of immunoglobulin E than the bolus dose, whereas the bolus was superior for reducing dexamethasone-induced psychotropic abnormalities. There were no significant changes in other parameters between the daily and the bolus dose. In conclusion, a daily dose of vitamin D in combination with dexamethasone is more efficacious for treating asthma in allergic rats than monotherapy. Key words: ovalbumin, dexamethasone, single dose, bolus dose. L'utilisation subaigue de corticosteroides provoque des effets secondaires comme l'intolerance au glucose, la dyslipidemie, l'anxiete et la depression, qui pourraient etre contrecarres par la vitamine D, une vitamine immuno-modulatrice. Les auteurs avaient pour but d'etudier l'efficacite antiasthmatique et le profil des effets secondaires de la vitamine D, de la dexamethasone et de leur combinaison, dans un modele d'inflammation des voies respiratoires induite par l'ovalbumine chez le rat. Deux doses differentes de vitamine D (50 UI/kg, i.p., quotidiennement pendant 2 semaines et 60000 UI/kg bolus) ont ete administrees en combinaison avec la dexamethasone (2,5 mg/kg, i.p. pendant 2 semaines) avant une provocation a l'ovalbumine. A la fin de la therapie, les parametres asthmatiques comme la numeration differentielle des globules blancs, les IgE du serum et du liquide de lavage broncho-alveolaire, l'IL-5 et le NO du serum etaient significativement accrus a la suite de la provocation chez les rats asthmatiques comparativement aux controles. Un tel accroissement etait significativement attenue par la combinaison ou monotherapie de vitamine D et de dexamethasone, la therapie combinee etant superieure a la monotherapie. L'hyperglycemie, l'hyperlipidemie et les troubles de comportements induits chez les rats allergiques par la dexamethasone etaient attenues par la vitamine D. La dose quotidienne etait plus efficace pour controler les IgE que le bolus, alors que le bolus etait plus efficace pour reduire les troubles du comportement que la dose quotidienne. Il n'y avait pas de changements significatifs des autres parametres entre la dose quotidienne et le bolus. En conclusion, une dose quotidienne de vitamine D combines a la dexamethasone est plus efficace pour traiter l'asthme chez les rats allergiques que la monotherapie. [Traduit par la Redaction] Mots-cles: ovalbumine, dexamethasone, dose unique, dose bolus.

The number of array faces is an important factor in determining antenna and radar system performance, cost, and manufacturing complexity. The subject of determining the optimum number of antenna faces has been addressed previously by several authors [1-5] using various figures of merit. For active phased array radars performing tracking and discrimination functions, the important figure of merit for antenna performance is power-aperture-gain (PAG) product. We determine the optimal number of laces by choosing PAG product as the figure of merit for the same tracking and discrimination performance at maximum scan angles. Given equal antenna performance at maximum scan angles in the coverage area, cost is the primary basis for comparison in the selection of the number of faces for a modern active phased array radar system.

The effect of various concentrations of several lead and mercury compounds upon various high affinity receptor sites within discrete brain regions has been measured. The specific binding of radioactive spiroperidol and quinuclidinyl benzilate to striatal and cortical membranes respectively, was much more severely inhibited in the presence of tri-n-butyl lead acetate than by lead acetate. This suggested that the hydrophobic organic lead derivative was able to interfere with receptor structure more readily than the lead acetate. On the other hand mercuric chloride was more effective in blocking these two neurotransmitter receptor sites than was the organic methylmercuric chloride. This implied that sulfhydryl groups may be within, or proximal to the allosteric binding site. The relative ineffectiveness of all heavy metal compounds studied in blocking the glycine. GABA or the diazepam receptors indicated that the mechanism of binding may not be similar with different receptor proteins. Since micromolar concentrations of some lead and mercury compounds suffice to severely inhibit neurotransmitter binding sites, such a direct interference with postsynaptic events may in part account for the neurological consequences of heavy metal poisoning.

We discuss strategies for designing active phased array antennas with high reliability. We show how to consider fault-tolerance in the design of the antenna architecture, so that replacement of failed components can be avoided for an extended period of time. First, we address the dependence of antenna life cycle cost on component failure rates. Then we discuss the design of active phased array architecture for maximizing antenna mean-time-between-failures (MTBF). The antenna MTBF is defined in terms of a specified degradation in peak sidelobe level. We present simulated data showing the effect of random, single, and clustered element failures on the peak sidelobe level of a low sidelobe antenna aperture. We use these data as a basis for analyzing various phased array architectures in terms of their antenna MTBF.

In active phased-array antennas, the transmit and receive functions are distributed at the antenna aperture using transmit and receive (T/R) modules. The use of T/R modules provides a significant improvement in antenna performance and flexibility in the choice of array architectures. In this paper, we present a review of various beamformer architectures for active phased-array antennas. This review is limited to corporate-fed active phased-array antennas for radar applications, as the general discussion to include all phased-array types is too broad for any one presentation. Beamformer architectures for narrow and wide bandwidth arrays, including the choice of applying an amplitude taper in the T/R module or beamformer network are discussed. Beamformer architectures that increase antenna reliability are also presented. Index Terms - Active arrays, phased arrays.

A previous study from our laboratory has shown the facilitatory effect of Ceratonia siliqua L. (Fabaceae) on the dopaminergic function. This study investigates the involvement of monoamines in the antidepressant activity of the total polyphenol content of Ceratonia siliqua extract (CS) in mice using a tail suspension test (TST) and forced swim test (FST). The immobility time in the TST and FST were significantly reduced by CS (25 and 50 mg kg-1, i.p.). The extract considerably attenuated the duration of immobility induced by prazosin (62.5 µg kg-1, i.p., an α-adrenoceptor antagonist) and eticlopride (0.1 µg kg-1, i.p., a classical D2-like dopamine receptor antagonist) in both TST and FST, whereas the extract could not modify the immobility in mice treated with p-chlorophenylalanine (100 mg kg-1, i.p., ×3 days; an inhibitor of serotonin synthesis) and baclofen (10 mg kg-1, i.p., GABAB agonist). This suggests that the antidepressant effect of CS is mediated by dopamine and noradrenaline. [ABSTRACT FROM AUTHOR]

Ginkgo bilobaextract (EGb), a potent antioxidant and monoamine oxidase B (MAO-B) inhibitor, was evaluated for its anti-parkinsonian effects in a 6-hydroxydopamine (6-OHDA) rat model of the disease. Rats were treated with 50, 100, and 150 mg/kg EGb for 3 weeks. On day 21, 2 µL 6-OHDA (10 µg in 0.1% ascorbic acid saline) was injected into the right striatum, while the sham-operated group received 2 µL of vehicle. Three weeks after 6-OHDA injection, rats were tested for rotational behaviour, locomotor activity, and muscular coordination. After 6 weeks, they were killed to estimate the generation of thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) content, to measure activities of glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD), and to quantify catecholamines, dopamine (DA) D2 receptor binding, and tyrosine hydroxylase-immunoreactive (TH-IR) fibre density. The increase in drug-induced rotations and deficits in locomotor activity and muscular coordination due to 6-OHDA injections were significantly and dose-dependently restored by EGb. The lesion was followed by an increased generation of TBARS and significant depletion of GSH content in substantia nigra, which was gradually restored with EGb treatment. EGb also dose-dependently restored the activities of glutathione-dependent enzymes, catalase, and SOD in striatum, which had reduced significantly by lesioning. A significant decrease in the level of DA and its metabolites and an increase in the number of dopaminergic D2 receptors in striatum were observed after 6-OHDA injection, both of which were significantly recovered following EGb treatment. Finally, all of these results were exhibited by an increase in the density of TH-IR fibers in the ipsilateral substantia nigra of the lesioned group following treatment with EGb; the lesioning had induced almost a complete loss of TH-IR fibers. Considering our behavioural studies, biochemical analysis, and immunohistochemical observation, we conclude that EGb can be used as a therapeutic approach to check the neuronal loss following parkinsonism. [ABSTRACT FROM AUTHOR]