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Acute Myocardial Infarction Inhibits the Neurogenic Tachycardic and Vasopressor Response in Rats via Presynaptic Cannabinoid Type 1 Receptor
Get PDFABSTRACT The present study was carried out to examine whether acute experimental myocardial infarction affects the sympathetic transmission to vessels and the heart of pithed rats via a presynaptic mechanism and, if so, to check whether inhibitory presynaptic cannabinoid (CB) receptors and endocannabinoids are involved in this response. In pithed and vagotomized rats, electrical stimulation (0.75 Hz; 1 ms; 50 V; 5 or 15 pulses for increases in heart rate or blood pressure, respectively) of the preganglionic sympathetic nerve fibers or intravenous injection of isoprenaline (0.1 nmol/kg) or noradrenaline (1 nmol/kg) increased heart rate and blood pressure by approximately 50 beats/min and 40 mm Hg, respectively. Ligation of the left coronary artery reduced the electrically (as opposed to the chemically) induced tachycardic and pressor responses by approximately 30 to 40%. The inhibitory effect of myocardial infarction was prevented by the CB 1 receptor antagonist rimonabant but not by the CB 2 receptor antagonist N- [(1S)-endo-1,3,3-trimethyl-bicyclo[2 Our results demonstrate that during the early phase of myocardial infarction the activation of presynaptic CB 1 receptors by endogenously formed cannabinoids contributes to the inhibition of the neurogenic tachycardic and vasopressor responses. Thus, the CB 1 receptor-mediated inhibition of excessive noradrenaline release from the sympathetic nerve fibers innervating the heart and vessels might play a protective role in myocardial ischemia. .2.1]heptan-2-yl]-5-(4-chloro-3
JianMin H. Effect of Aloe vera polysaccharides on immunity and antioxidant activities in oral ulcer animal models. Carbohydrate Polymers 2009; 75
No full texta b s t r a c t Aloe vera polysaccharides have traditionally been used in Asian cultures as medicinal plants to enhance immunity and reduce oxidative injury. The current investigation was conducted to examine the effects of A. vera polysaccharides on various in vivo parameters of innate immunity and antioxidant enzymes activities in oral ulcer animals. Forty wistar rats were randomly divided into the following 1 control group and 3 experimental groups (each group contained 10 rats). Rats in experimental groups were orally fed by A. vera polysaccharides. Rats in control group were orally fed by same volume of saline. The results showed that A. vera polysaccharides enhanced immunity activity and exerted antioxidant effects compared with vehicle controls. These results demonstrate, for the first time, that A. vera polysaccharides are effective in enhancing innate immunity and suppressing oxidative injury in oral ulcer animals
RNA Interference as a New Tool in Therapeutics
Get PDFSummary The basic principle of RNA interference, a possible new therapeutic tool, involves destruction of messenger RNA upon interaction with homologous double-stranded RNA present in the cell cytoplasm. Studies have shown that both viral and non-viral small interfering RNA delivery methods and delivery of chemically synthesized small interfering RNAs to the cell can provide selective gene suppression through this mechanism, both in vitro and in vivo. Before becoming a functional therapeutic tool, there are a number of problems concerning RNA interference that should be solved. Major problems involve off--target effects, insertional mutagenesis and malignant transformation, as well as problems of delivery methods and reduction of toxicity
Yajima: Biodegradation of an s-triazine herbicide, simazine
No full textAbstract Two types of simazine-degrading microorganisms were isolated from soil samples where the herbicide had been spread with the enrichment culture using simazine as the sole carbon and nitrogen source. A fungal strain, DS6F, identified as Penicillium steckii, is the first simazine-degrading fungus ever reported. Ž Simazine was gradually degraded by P. steckii DS6F in the mineral medium containing simazine initial concentration: . 50 mgrl and 25 mgrl of yeast extract. The rate of simazine degradation was improved when assimilable carbon sources were added into the medium, and the reduction rate of 53% was obtained after 5 days of cultivation at 308C when glucose was added into the basal medium. Ž . The bacterial strain, N5C, identified as Moraxella Branhamella oÕis, was newly isolated and proven to degrade simazine more effectively than strain, DS6F, and 200 mgrl of simazine disappeared almost completely within 5 days at 358C. Ž . M. Branhamella oÕis could also degrade another s-triazine herbicide, atrazine, at the similar reduction rate as simazine.
Author's personal copy Behavioural Inhibition System (BIS) sensitivity differentiates EEG theta responses during goal conflict in a continuous monitoring task
No full textPrevious research has revealed that EEG theta oscillations are affected during goal conflict processing. This is consistent with the behavioural inhibition system (BIS) theory of anxiet
X-RAY ABSORPTION STUDIES OF GE LAYERS BURIED IN SILICON CRYSTAL
No full textThe physical properties of quantum confined semiconductor heterostructures have attracted wide attention both from the experimental and theoretical point of view because of their potential applications in microelectronics and optoelectronics. The growth mechanisms are closely related to both self-assembly nanocrystal formation exhibiting three-dimensional quantum-confinement effects and band engineering. Due to the well elaborated grown technology of Si and Ge crystals and the large lattice mismatch (about 4%) the particular attention is paid to the Ge/Si system. Therefore, the mechanisms taking place during the Ge quantum dots formation are of particular interest. Several studies have been reported on the interface structure and growth morphologies of Ge on Si crystal [1-4] but researchers are still far from understanding and controlling the evaluation and morphology of interface. Recognizing the advantages of X-ray absorption spectroscopy as being a local atom probe and a fingerprint of atom chemical bonding we applied this spectroscopy to study of the local arrangement and chemical bonding of Ge monolayers buried in Si. The XANES and EXAFS spectra have been measured at room temperature at the A1 station in HASYLAB using double crystal Si (111) monochromator. The experiments were done at the K-edge of Ge using five elements Ge fluorescence detector. Samples with 6 to 20 monolayers of Ge were grown at Si (001) oriented crystal and covered by 200 Å of Si. The angles between samples surface and X-ray beam were 20 0 and 75 0 . Therefore, taking into account polarization effects one can study bonds out of sample plane (20 0 ) and in plane (75 0 ). The powdered monocrystal of Ge was measured as a reference in transmission mode. Figures 1 and 2 report the X-ray absorption Ge K near-edge spectra of Ge layers buried in Si with thickness 6 and 20 monolayers, respectively, and Ge -crystal as reference. All spectra are normalized to the same intensity before the edge and at the end of the spectra. Considerable changes in spectra for the layers with different thickness, measured at two orientations in respect to the polarization vector of the radiation, were observed. These changes indicate on the change of the morphology of the formed layers with increase of the layers thickness in the considered directions. Comparing spectra from 6ML sample with that of 20M
Semiclassical approximation of the radial equation with two-dimensional potentials
Get PDFAbstract. The radial equation for scattering from a cylindrically symmetrical potential is examined, because two-dimensional scattering arises in high-energy electron diffraction from crystals. Particular attention is paid to the case of s waves, where there is a centripetal attractive potential for free particles. After showing that the Langer transformation, which leads to correct semiclassical wavefunctions for all other cases in two and three dimensions, fails for s waves, we apply the method of comparison equations, which enables us to express the phase shifts and bound state conditions in a simple form valid for all angular momenta. We test the theory for s waves by comparison with exactly-calculated energy levels
Collaborative IDS Framework for Cloud
Get PDFAbstract Cloud computing is used extensively to deliver utility computing over the Internet. Defending network accessible Cloud resources and services from various threats and attacks is of great concern. Intrusion Detection System (IDS) has become popular as an important network security technology to detect cyber-attacks. In this paper, we propose a novel Collaborative IDS (CIDS) Framework for cloud. We use Snort to detect the known stealthy attacks using signature matching. To detect unknown attacks, anomaly detection system (ADS) is built using Decision Tree Classifier and Support Vector Machine (SVM). Alert Correlation and automatic signature generation reduce the impact of Denial of Service (DoS) /Distributed DoS (DDoS) attacks and increase the performance and accuracy of IDS
This content has been downloaded from IOPscience. Please scroll down to see the full text. Validating biorobotic models Validating biorobotic models *
No full textAbstract Some issues in neuroscience can be addressed by building robot models of biological sensorimotor systems. What we can conclude from building models or simulations, however, is determined by a number of factors in addition to the central hypothesis we intend to test. These include the way in which the hypothesis is represented and implemented in simulation, how the simulation output is interpreted, how it is compared to the behaviour of the biological system, and the conditions under which it is tested. These issues will be illustrated by discussing a series of robot models of cricket phonotaxis behaviour