The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform

Perry F Renshaw - One of the best experts on this subject based on the ideXlab platform.

  • citicoline enhances frontal lobe bioenergetics as measured by phosphorus magnetic resonance spectroscopy
    NMR in Biomedicine, 2008
    Co-Authors: Marisa M Silveri, J Dikan, Amy J Ross, J Jensen, Toshikazu Kamiya, Yoko Kawada, Perry F Renshaw
    Abstract:

    Citicoline supplementation has been used to ameliorate memory disturbances in older people and those with Alzheimer's disease. This study used MRS to characterize the effects of citicoline on high-energy phosphate metabolites and constituents of Membrane synthesis in the frontal lobe. Phosphorus ((31)P) metabolite data were acquired using a three-dimensional chemical-shift imaging protocol at 4 T from 16 healthy men and women (mean +/- SD age 47.3 +/- 5.4 years) who orally self-administered 500 mg or 2000 mg Cognizin Citicoline (Kyowa Hakko Kogyo Co., Ltd, Ibaraki, Japan) for 6 weeks. Individual (31)P metabolites were quantified in the frontal lobe (anterior cingulate cortex) and a comparison region (parieto-occipital cortex). Significant increases in phosphocreatine (+7%), beta-nucleoside triphosphates (largely ATP in brain, +14%) and the ratio of phosphocreatine to inorganic phosphate (+32%), as well as significant changes in Membrane Phospholipids, were observed in the anterior cingulate cortex after 6 weeks of citicoline treatment. These treatment-related alterations in phosphorus metabolites were not only regionally specific, but tended to be of greater magnitude in subjects who received the lower dose. These data show that citicoline improves frontal lobe bioenergetics and alters Phospholipid Membrane turnover. Citicoline supplementation may therefore help to mitigate cognitive declines associated with aging by increasing energy reserves and utilization, as well as increasing the amount of essential Phospholipid Membrane components needed to synthesize and maintain cell Membranes.

Neal K. Devaraj - One of the best experts on this subject based on the ideXlab platform.

  • In Situ Lipid Membrane Formation Triggered by Intramolecular Photoinduced Electron Transfer.
    Langmuir : the ACS journal of surfaces and colloids, 2017
    Co-Authors: Takafumi Enomoto, Roberto J. Brea, Ahanjit Bhattacharya, Neal K. Devaraj
    Abstract:

    A major goal of synthetic biology is the development of rational methodologies to construct self-assembling non-natural Membranes, which could enable the efficient fabrication of artificial cellular systems from purely synthetic components. However, spatiotemporal control of artificial Membrane formation remains both challenging and limited in scope. Here, we describe a new methodology to promote biomimetic Phospholipid Membrane formation by the photochemical activation of a catalyst-sensitizer dyad via an intramolecular photoinduced electron-transfer process. Our results offer future opportunities to exert spatiotemporal control over artificial cellular constructs.

  • Spontaneous Phospholipid Membrane Formation by Histidine Ligation
    Synlett, 2016
    Co-Authors: Roberto J. Brea, Ahanjit Bhattacharya, Neal K. Devaraj
    Abstract:

    A major challenge for the construction of artificial lipid Membranes is the development of simple and robust methods for mimicking natural Phospholipid Membrane generation. Here we describe a nonenzymatic and chemoselective approach that relies on histidine ligation to form Phospholipids de novo from water-soluble amphiphilic precursors. The resulting Phospholipids can spontaneously self-assemble into micron-sized vesicles and encapsulate biomacromolecules.

  • spontaneous reconstitution of functional transMembrane proteins during bioorthogonal Phospholipid Membrane synthesis
    Angewandte Chemie, 2015
    Co-Authors: Christian M Cole, Roberto J. Brea, Young Hun Kim, Michael D Hardy, Jerry Yang, Neal K. Devaraj
    Abstract:

    TransMembrane proteins are critical for signaling, transport, and metabolism, yet their reconstitution in synthetic Membranes is often challenging. Non-enzymatic and chemoselective methods to generate Phospholipid Membranes in situ would be powerful tools for the incorporation of Membrane proteins. Herein, the spontaneous reconstitution of functional integral Membrane proteins during the de novo synthesis of biomimetic Phospholipid bilayers is described. The approach takes advantage of bioorthogonal coupling reactions to generate proteoliposomes from micelle-solubilized proteins. This method was successfully used to reconstitute three different transMembrane proteins into synthetic Membranes. This is the first example of the use of non-enzymatic chemical synthesis of Phospholipids to prepare proteoliposomes.

Roberto Righini - One of the best experts on this subject based on the ideXlab platform.

  • Partitioning of an anchor dipeptide in a Phospholipid Membrane.
    The journal of physical chemistry. B, 2009
    Co-Authors: Victor Volkov, Roberto Righini
    Abstract:

    We explore the localization of a guest N-myristoylated methyl glycine anchor dipeptide in a Phospholipid environment. The dipeptide is part of a conservative sequence, which ensures proper association of a wide group of proteins in living organisms with a cellular Phospholipid Membrane. Using linear and two-color anharmonic infrared spectroscopy, we measure relative degrees of hydration of the amide I modes of the dipeptide and of Phospholipid carbonyls. The atomic density of water in dependence of the distance from the hydrophobic center of the bilayer (a result of an independent Neutron scattering experiment) allows us to determine the relative altitudes of the peptide carbonyls with respect to those of the Phospholipid ones. Considering this, and the dimensions of the dipeptide molecular frame, we anticipate the average angle between the backbone of the dipeptide and the normal to the Membrane surface. The results provide a descriptive picture of the depth and geometry of partitioning of a guest N-myristoylated methyl glycine anchor dipeptide into a Phospholipid Membrane.

  • Distinct water species confined at the interface of a Phospholipid Membrane
    Physical review letters, 2007
    Co-Authors: Victor Volkov, D. Jason Palmer, Roberto Righini
    Abstract:

    The physics of confined water has stimulated extensive research in recent years, in particular, regarding the role of hydrogen bonding as a significant factor in the observed dynamics. In this work, two-dimensional infrared spectroscopy was employed to investigate the response of the OH moiety of water in Phospholipid Membrane samples. The results show strong evidence for three distinct hydrogen bonding motifs (H 2 O with zero, one, or both OH moieties hydrogen bonded), whose relative proportions at the Membrane interface are estimated.

Junjing Yin - One of the best experts on this subject based on the ideXlab platform.

  • Phospholipid Membrane decorated deep penetrated nanocatalase relieve tumor hypoxia to enhance chemo photodynamic therapy
    Acta Pharmaceutica Sinica B, 2020
    Co-Authors: Junjing Yin, Haiqiang Cao, Hong Wang, Kaoxiang Sun, Zhiwen Zhang
    Abstract:

    Abstract Hypoxia is a serious impediment to current treatments of many malignant tumors. Catalase, an antioxidant enzyme, is capable of decomposing endogenous hydrogen peroxide (H2O2) into oxygen for tumor reoxygenation, but suffered from in vivo instability and limited delivery to deep interior hypoxic regions in tumor. Herein, a deep-penetrated nanocatalase-loading DiIC18 (5, DiD) and soravtansine (Cat@PDS) were provided by coating catalase nanoparticles with PEGylated Phospholipids Membrane, stimulating the structure and function of erythrocytes to relieve tumor hypoxia for enhanced chemo-photodynamic therapy. After intravenous administration, Cat@PDS preferentially accumulated at tumor sites, flexibly penetrated into the interior regions of tumor mass and remarkably relieved the hypoxic status in tumor. Notably, the Cat@PDS + laser treatment produced striking inhibition of tumor growth and resulted in a 97.2% suppression of lung metastasis. Thus, the Phospholipids Membrane-coated nanocatalase system represents an encouraging nanoplatform to relieve tumor hypoxia and synergize the chemo-photodynamic cancer therapy.

A Elsagh - One of the best experts on this subject based on the ideXlab platform.

  • quantum study of solvent effect with popc Phospholipid bilayers in a cell Membrane and its impact on active and targeted drug delivery
    Eurasian Chemical Communications, 2020
    Co-Authors: A Elsagh
    Abstract:

    In this study, since the system was relatively large, the modified methods of molecular mechanics and quantum mechanics were used to obtain changes in the thickness of the Membrane Phospholipids by different solvents. Thus, according to the theory of fluidity Mosaic, the changes that were made due to various solutions and, consequently, the constant change of solution dielectric effect on the thickness of the Phospholipid Membrane. By comparing these changes, it was found that changes in the width of the inner layers in the vicinity of different solvents, with the shift from this effect, are consistent with the total width of the Phospholipid Membrane. It seems to be the determining factor in changing the width of the diaphragm against different solvents of the Phospholipid inner layer. Accordingly, the depth of Membrane thinning was calculated for each solvent in comparison with the water solution, which was reduced by decreasing the solvent dielectric constant, thinning of the solution and the Phospholipid Membrane, respectively. Thermodynamic functions for the usual solution were calculated using frequency studies and thermodynamic relations. These functions indicate that the system is stable in terms of thermodynamics and stabilizes the desired solution without distorting structural integrity. Hence, these structures can be used as agents for the delivery, exchange, and absorption of materials. The Membrane structures studied in this study are used in the mechanism, and drug delivery interactions in the body and the pharmaceutical industry as a channel for the delivery and exchange, and these results can be used in the discussion of intelligent redeploy of drugs and Nano drug. So, paying attention to the operating environment and the thinning factor and the thickness of the Membrane increase the reactivity, improve the solubility and delivery of drugs, reduce the dose of the medicine and increase its effectiveness.