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11.

Background:

In previous studies, the neuroprotective effect of 17β-estradiol in diffuse traumatic brain injury has been shown. This study used ICI 182,780, a non-selective estrogen receptor antagonist, to test the hypothesis that the neuroprotective effect of 17β-estradiol in traumatic brain injury is mediated by the estrogen receptors.

Methods:

The ovariectomized rats were divided into eight groups. Brain injury was induced by Marmarou’s method. Estrogen was injected 30 minutes after traumatic brain injury, and ICI 182,780 was injected before traumatic brain injury and also before estrogen treatment. In one group only ICI 182,780 was injected. The brain water content and Evans blue dye content were measured 24 and 5 hours after traumatic brain injury, respectively. The neurologic outcomes and intracranial pressure were assessed before, 4, and 24 hours after traumatic brain injury.

Results:

Brain water content and Evans blue content were less in estrogen-treated group comparison to vehicle group. ICI 182,780 eliminated the effects of estrogen on brain edema and brain blood barrier permeability. Intracranial pressure was increased significantly after trauma, and estrogen decreased intracranial pressure at 4 and 24 hours after traumatic brain injury in comparison to vehicle. This inhibitory effect was also eliminated by treatment with ICI182,780. ICI 182,780 also inhibited the estrogen induced increase in neurologic outcomes following traumatic brain injury. However, the use of ICI 182,780 alone had no neuroprotective effect after traumatic brain injury.

Conclusion:

The results suggest that classical estrogen receptors have probably a role in the neuroprotective function of estrogen following traumatic brain injury.Key Words: Estrogens, Intracranial pressure (ICP), Brain edema  相似文献   
12.
Background:Despite introduction of modern antiepileptic drugs, 30% of epileptic patients are still drug resistant. Remarkable three-dimensional spatial structure of AdCA, yet the simplicity of the molecule, makes AdCA a promising lead compound. Methods:Sedative/motor impairment and 24-h mortality rate of AdCA were determined in mice. Impact of AdCA on (1) threshold and occurrence of clonic seizures induced by PTZ in mice, (2) incidence of tonic seizures induced by MES in mice, and (3) incidence of generalized seizures and duration of evoked afterdischarges in amygdala-kindled rats, were determined. The role of benzodiazepine receptors in the AdCA effect on clonic seizure threshold was also assessed. Results:AdCA showed sedative effect (TD50 = 224.5 [190.2-289.9] mg/kg). LD50 = 805.5 (715.2–988.1) mg/kg was obtained for AdCA. The compound increased PTZ seizure threshold from 180 mg/kg (p < 0.05) and also inhibited the incidence of clonic seizures (ED50 = 256.3 [107.4-417.3] mg/kg). AdCA also decreased afterdischarge duration (p < 0.01) and the incidence of generalized seizures (ED50 < 50 mg/kg) in the kindled rats. However, AdCA did not protect mice against tonic seizures induced by MES. The benzodiazepine receptor antagonist flumazenil prevented the increase of seizure threshold by AdCA. Conclusion:AdCA possesses anticonvulsant activity in kindling and PTZ models through the activation of benzodiazepine/GABAA receptors with acceptable therapeutic index. Key Words: Anticonvulsants, Flumazenil, Pentylenetetrazole  相似文献   
13.
Abstract

Experimental results indicate the existence of an inducible system that can temporarily help cereal plants to defend themselves against cereal aphids. The induction is released by volatiles emitted when aphids attack a neighbour plant individual. Similar effects are obtained with mildew attacked plants. The system shows moderate specificity and affects the allocation of biomass in the plant.  相似文献   
14.
The recent decreasing worldwide supplies of marine oils have forced the aquaculture industry to investigate alternative lipid sources for use in marine fish feeds. The aim of this study was to determine the impact of dietary replacement of fish oil by vegetable oils on gilthead seabream (Sparus aurata) growth performance, nutritive utilization, body composition, and fatty acid profile as well as feed cost. Two dietary vegetable oil (VO) mix blends (VO1 and VO2) in which: sunflower (SO), cottonseed (CO) and linseed (LO) for VO1 or soybean oil (SBO) for VO2, were tested as 60% fish oil (FO) substitutes versus the 100% FO control or reference diet (FO). Three iso-proteic (46% CP) and iso-lipidic (18%) experimental diets were hand fed, twice a day, 6 days a week to apparent visual satiety to triplicate groups of seabream growers (average initial weight, 130.9 ± 3.44 g), until fish reached market size (300–400 g/fish) after 20 weeks at mean ambient temperature 27.0 ± 1.8°C. All experimental diets were well accepted by seabream growers regardless of the different lipid sources used, as overall mean feed intake (FI) and daily intake (DFI) were not significantly different (P > 0.05) among dietary treatments. In terms of growth performance, fish fed VO1 diet (with LO) exhibited a relatively lower, but significant (P < 0.05), total weight gain (WG) than fish fed all FO diet (FO). However, mean value of WG of fish fed either vegetable oil-tested diet was nonsignificantly different. Feeding seabream growers vegetable oil (VO) diets (VO1 or VO2) had no significant effect on specific growth rate (SGR), daily weight index (DWI), or feed conversion ratio (FCR) among dietary treatments. Consumption of VO for 20 weeks did not significantly alter the major nutrient composition of fish, but the muscle fatty acid (FA) profile was significantly altered compared to the reference FO diet. Comparatively reduced levels of eicosapentaenoic acid (EPA) and docosahexaenoic acids (DHA), as well as elevated levels of linoleic and linolenic acids (LA and LNA) compared with fish fed the FO were noticed. In terms of economics, 17 or 20% reduction in Kg feed cost was obtained for diets VO1 or VO2, respectively. In terms of growth performance and cost, VO2 diet showed slight relative superiority over VO1 diet. However, in terms of liver structure morphology, VO1 diet (with LO) has resulted in less fat-infiltration and altered hepatic cells than VO2 (with SBO). As these traits do not affect yield or the price paid for the fish, VO2 diet has therefore been considered better than VO1 as complementary lipid sources for gilthead seabream grower diets.  相似文献   
15.
The major constituents of the oil of Lavandula angustifolia Mill were estimated as borneoll (8.57%), alpha terpinene (6.22%), linolool (4.91%) geranyl proprionate (3.76%), butanoic acid hexyl ester (2.99%) and caryophyllene oxide (2.72%). LC10, LC30 and LC50 were estimated as 0.31%, 0.705% and 1.24% respectively. The sublethal concentration (LC30) of essential oil affected the nutritional indices of 4th instar larvae of Glyphodes pyloalis. The essential oil reduced total protein, carbohydrate and lipid when compared with the control. All concentrations (0.25%, 0.5%, 1%, and 2%) of essential oil affected the major macromolecules and activities of key enzyme in G. pyloalis.  相似文献   
16.
17.
Background:Hereditary spherocytosis and hereditary dRTA are associated with mutations in the SLC4A1 gene encoding the AE1. In this study, some patients with clinical evidence of congenital HS and renal symptoms were investigated. Methods:Twelve patients with congenital HS and renal symptoms were recruited from Ali-Asghar Children’s Hospital (Tehran, Iran). A patient suspected of having dRTA was examined using WES method, followed by Sanger sequencing. Results:One patient (HS03) showed severe failure to thrive, short stature, frequent urinary infection, and weakness. A homozygote (rs571376371 for c.2494C>T; p.Arg832Cys) and a heterozygote (rs377051298 for c.466C>T; p.Arg156Trp) missense variant were identified in the SLC4A1 and SPTA1 genes, respectively. The compound heterozygous mutations manifested as idRTA and severe HS in patient HS03. Conclusion:Our observations, for the first time, revealed clinical and genetic characteristics of idRTA and severe HS in an Iranian patient HS03. Key Words: Erythrocyte membrane protein, Hereditary spherocytosis, Hemolytic anemia, Whole-exome sequencing  相似文献   
18.
ABSTRACT

Background: Traditional field-based methods of measurement of biomass and carbon storage face difficulty in collecting time-consuming and expensive, suggests the use of remote sensing-based techniques. It estimates the economic value of the aboveground biomass (AGB) using satellite remote sensing across the Hyrcanian forests of Iran. Methods: The Landsat-8 OLI sensor data were combined with field-based allometric information of 186 circular sample plots. The AGB was calculated at the plot level using the collected data and specific volumetric mass for species in the studied area. It was followed by calculating the carbon storage using a 50% carbon coefficient and the photosynthesis equation at the forest parcel level. Model results using the random forest and support vector machines. The carbon sequestration value was calculated with USD 25.3 as a shadow value of carbon in 2014 and using the replacement cost approach. Results: The highest performances achieved by RF for biomass, carbon storage and the carbon storage value (Iranian Rials of 0.67% and 16%, respectively). The value was derived once at the plot level of 12.22 million IRR (370.43 USD) per ha. In addition, at the parcel level, which resulted in an estimated value of 12.87 million IRR (390.24 USD) per ha.  相似文献   
19.
Quantum computers, besides offering substantial computational speedups, are also expected to preserve the privacy of a computation. We present an experimental demonstration of blind quantum computing in which the input, computation, and output all remain unknown to the computer. We exploit the conceptual framework of measurement-based quantum computation that enables a client to delegate a computation to a quantum server. Various blind delegated computations, including one- and two-qubit gates and the Deutsch and Grover quantum algorithms, are demonstrated. The client only needs to be able to prepare and transmit individual photonic qubits. Our demonstration is crucial for unconditionally secure quantum cloud computing and might become a key ingredient for real-life applications, especially when considering the challenges of making powerful quantum computers widely available.  相似文献   
20.
The species of Glaucium have been used in Iranian herbal medicine in the treatment of dermatitis. Due to anti-inflammatory and analgesic activity of Glaucium grandiflorum methanolic extract in i.p. administration, these effects in topical administration were studied using carrageenan-induced edema and formalin test. Several formulations were prepared and the best cream was chosen as vehicle. Piroxicam gel and methyl salicylate ointment were studied as positive control for anti-inflammatory and analgesic activity, respectively. The edema inhibition of preparations containing extract at the doses of 1-5% w/w were significantly different from control group. The anti-inflammatory effect of MS4-5% was similar to the effect of piroxicam gel at 3 h after carrageenan injection. Topical preparation containing G. grandiflorum methanolic extract showed analgesic effect in concentrations more than 4% w/w in early phase in formalin test. This activity was observed in concentrations more than 3% w/w in late phase. The topical analgesic activity of extract was less than the analgesic activity of methyl salicylate ointment.  相似文献   
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