RESUMEN
OBJECTIVE: Hydroethanolic extract of Zanthoxylum alatum seeds (HEZA) in scopolamine-induced amnesia was investigated for memory enhancing activity. MATERIALS AND METHODS: Radial arm maze (RAM) test was performed to evaluate the behavioral activity. Rats were treated with HEZA (50, 100, and 200 mg/kg, p. o.) and tacrine (3 mg/kg. i. p.) for 14 days. Scopolamine (0.4 mg/kg) was injected i. p. into rats after 45 min of drug administration on the 14th day. The messenger RNA (mRNA)/protein profile of few markers (acetylcholinesterase [AChE], heme oxygenase-1 [HO-1], nuclear factor-kappa B [NFκB], nuclear factor erythroid 2-related factor 2 [Nrf2], protein phosphatase 2A[PP2A], Tau, brain-derived neurotrophic factor [BDNF], tropomyosin-related kinase B [TrkB], Bcl-2-associated X protein [Bax], and Caspase-3) were also measured by polymerase chain reaction (PCR) and immunoblotting assay. Brain cytokines (tumor necrosis factor alpha [TNF-α], interleukin [IL]-1 ß, and IL-10) in hippocampus were evaluated using commercially available enzyme-linked immunosorbent assay kits. RESULTS: HEZA exhibited anti-amnesic activity as indicated by a significant reduction in the working memory error and reference memory error in RAM. Pretreatment with HEZA significantly down-regulated the expression of AChE, NFκB, Tau, Bax, and Caspase-3 with simultaneous up-regulation of Nrf2, HO-1, PP2A, BDNF, and TrkB genes in the hippocampal tissues similar to tacrine when compared with scopolamine-treated rats. Pretreatment with HEZA attenuated scopolamine-induced elevation of TNF-α, IL-1 ß, levels in hippocampus and reversed diminished IL-10 concentrations towards normal levels in the brain. CONCLUSION: Zanthoxylum alatum seeds could probably counteract amnesia. Since its use is mainly reported as a stimulant and tonic, this novel activity could be a boon for the scientists to explore more in this direction.
Asunto(s)
Amnesia/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Extractos Vegetales/uso terapéutico , Zanthoxylum , Acetilcolinesterasa/genética , Amnesia/inducido químicamente , Amnesia/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Citocinas/metabolismo , Hemo Oxigenasa (Desciclizante)/genética , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Factor 2 Relacionado con NF-E2/genética , FN-kappa B/genética , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/toxicidad , Fitoterapia , Extractos Vegetales/farmacología , Extractos Vegetales/toxicidad , Proteína Fosfatasa 2/genética , Ratas Wistar , Receptor trkB/metabolismo , Escopolamina , Semillas , Pruebas de Toxicidad Aguda , Proteína X Asociada a bcl-2/metabolismo , Proteínas tau/genéticaRESUMEN
We have calculated the high harmonic generation spectra from Xe atom by imposing different kinds of absorbing potentials. Owing to the center of inversion of the model system, one should get odd harmonics only. However, using negative imaginary potentials as an absorbing boundary condition, we have also got even order harmonics along with the odd order harmonics. These non-odd order harmonics are generated due to the spurious reflections occurring at the grid boundary. On the contrary, when smooth exterior scaling methods are used as an absorbing boundary condition, only odd order harmonics are obtained. Hence, smooth exterior scaling methods impose proper absorbing boundary condition.
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Recently, occurrence of coalescence point was reported in H(2)(+) undergoing multiphoton dissociation in strong laser field. We have applied parametric equations of motion and smooth exterior scaling method to study the coalescence phenomenon of H(2)(+). The advantage of this method is that one can easily trace the different states that are changing as the field parameters change. It was reported earlier that in the parameter space, only two bound states coalesce [R. Lefebvre, O. Atabek, M. Sindelka, and N. Moiseyev, Phys. Rev. Lett. 103, 123003 (2009)]. However, it is found that increasing the accuracy of the calculation leads to the coalescence between resonance states originating from the bound and the continuum states. We have also reported many other coalescence points.
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We have applied parametric equations of motion (PEM) to study photodissociation dynamics of H(2)(+). The resonances are extracted using smooth exterior scaling method. This is the first application of PEM to non-Hermitian Hamiltonian that includes resonances and the continuum. Here, we have studied how the different resonance states behave with respect to the change in field amplitude. The advantage of this method is that one can easily trace the different states that are changing as the field parameter changes.
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Here, we propose a new complex path to achieve better absorption during the propagation of a wavepacket. In the proposed modified smooth exterior scaling (SES) method, scaling function, θ(x), has been chosen as a real function rather than complex (as used in a conventional smooth exterior scaling method). It greatly reduces the artificial reflections from the boundary edges. This modified SES method is applied to study the multiphoton dissociation of H(2)(+) in intense laser field. The resonance states are calculated accurately.