Search results for "Modulator"

Dispersion Compensation in Holograms Reconstructed by Femtosecond Light Pulses

2014

This chapter describes how the spatiotemporal dispersion associated with the diffraction of broadband femtosecond light pulses through computer generated holograms (CGHs) can be compensated to a first order with a properly designed dispersion compensation module (DCM). The angular dispersion of the beam associated to CGHs leads to both spatial and temporal distortion of the pulse. Some experiments in one-shot second harmonic generation, wide-field two-photon microscopy, and parallel micromachining are shown to study the quality of the compensation performed with the DCM.

Q-switched all-fibre laser using a fibre-optic resonant acousto-optic modulator

2007

Abstract We report an actively Q-switched all-fibre laser using a fibre-optic resonant acousto-optic modulator as Q-switching element. The modulator consists of a short-length fibre Bragg grating modulated by a standing longitudinal elastic wave, being the grating length much shorter than the acoustic wavelength. Q-switch pulses were successfully obtained from an Er3+-doped fibre laser at repetition rates of 18 and 37 kHz.

Synthesis of N-acyl Derivatives of Aminocombretastatin A-4 and Study of their Interaction with Tubulin and Downregulation of c-Myc.

2021

11 p.-9 fig.-4 tab.

Preclinical evidence of new opioid modulators for the treatment of addiction.

2010

Addiction to opiates is one of the most severe forms of substance dependence, and despite a variety of pharmacological approaches to treat it, relapse is observed in a high percentage of subjects. New pharmacological compounds are necessary to improve the outcome of treatments and reduce adverse side effects. Moreover, drugs that act on the opioid system can also be of benefit in the treatment of alcohol or cocaine addiction. AREA COVERED BY THIS REVIEW: Recent preclinical studies of pharmacological agents for the treatment of opiate addiction (2008 to the present date).The reader will be informed of the latest drugs shown in animal models to modify dependence on opiates and the reinforcing…

Design, synthesis, and biological evaluation of thiophene analogues of chalcones.

2008

Chalcones are characterized by possessing an enone moiety between two aromatic rings. A series of chalcone-like agents, in which the double bond of the enone system is embedded within a thiophene ring, were synthesized and evaluated for antiproliferative activity and inhibition of tubulin assembly and colchicine binding to tubulin. The replacement of the double bond with a thiophene maintains antiproliferative activity and therefore must not significantly alter the relative conformation of the two aryl rings. The synthesized compounds were found to inhibit the growth of several cancer cell lines at nanomolar to low micromolar concentrations. In general, all compounds having significant anti…

Abnormal mitotic spindle assembly and cytokinesis induced by D-Limonene in cultured mammalian cells

2013

D-Limonene is found widely in citrus and many other plant species; it is a major constituent of many essential oils and is used as a solvent for commercial purposes. With the discovery of its chemotherapeutic properties against cancer, it is important to investigate the biological effects of the exposure to D-Limonene and elucidate its, as yet unknown, mechanism of action. We reported here that D-Limonene is toxic in V79 Chinese hamster cells in a dose-dependent manner. Moreover, to determine the cellular target of D-Limonene, we performed morphological observations and immunocytochemical analysis and we showed that this drug has a direct effect on dividing cells preventing assembly of mito…

The Emerging Role of the Endocannabinoid System in Endocrine Regulation and Energy Balance

2005

During the last few years, the endocannabinoid system has emerged as a highly relevant topic in the scientific community. Many different regulatory actions have been attributed to endocannabinoids, and their involvement in several pathophysiological conditions is under intense scrutiny. Cannabinoid receptors, named CB1 receptor and CB2 receptor, first discovered as the molecular targets of the psychotropic component of the plant Cannabis sativa, participate in the physiological modulation of many central and peripheral functions. CB2 receptor is mainly expressed in immune cells, whereas CB1 receptor is the most abundant G protein-coupled receptor expressed in the brain. CB1 receptor is expr…

Structural Determinants for the Mode of Action of Imidazopyridine DS2 at δ-Containing γ-Aminobutyric Acid Type A Receptors

2021

Despite the therapeutic relevance of δ-containing γ-aminobutyric acid type A receptors (GABAARs) and the need for δ-selective compounds, the structural determinants for the mode and molecular site of action of δ-selective positive allosteric modulator imidazo[1,2-a]pyridine DS2 remain elusive. To guide the quest for insight, we synthesized a series of DS2 analogues guided by a structural receptor model. Using a fluorescence-based fluorometric imaging plate reader membrane potential assay, we found that the δ-selectivity and the pharmacological profile are severely affected by substituents in the 5-position of the imidazopyridine core scaffold. Interestingly, the 5-methyl, 5-bromo, and 5-chl…

Characterization of a novel LPS-induced peptide from Ciona intestinalis with immune modulatory activities

2015

How many sites of action for endocannabinoids to control energy metabolism?

2006

The promising results obtained by clinical trials using Rimonabant to tackle visceral obesity and related disorders recently promoted a remarkable impulse to carry out detailed investigations into the mechanisms of action of endocannabinoids in regulating food intake and energy metabolism. The endocannabinoid system has been known for many years to play an important role in the modulation of the neuronal pathways mediating the rewarding properties of food. However, in the last few years, with the advanced understanding of the crucial role of the hypothalamic neuronal network in the regulation of appetite, several studies have also directed attention to the orexigenic role of the endocannabi…