Search results for "MIME"

DNA interaction of CuII, NiII and ZnII functionalized salphen complexes: studies by linear dichroism, gel electrophoresis and PCR.

2013

The interaction of salphen-type NiII, CuII and ZnII complexes with native DNA was investigated by exploiting linear dichroism experiments. The NiII complex behaves as a typical intercalator, binding strongly and stiffening and unwinding the DNA. The strength of the DNA interaction is slightly weaker for the copper complex and much weaker for the zinc complex. Plasmid-DNA gel electrophoresis experiments indicated that while CuII and ZnII complexes do not induce the unwinding of supercoiled DNA, the NiII complex has a nuclease activity without the addition of external agents. On the other hand, as shown in the PCR assays, we demonstrate that, at the used concentrations, only the CuII complex …

Physics of the nuclear pore complex: Theory, modeling and experiment

2021

Abstract The hallmark of eukaryotic cells is the nucleus that contains the genome, enclosed by a physical barrier known as the nuclear envelope (NE). On the one hand, this compartmentalization endows the eukaryotic cells with high regulatory complexity and flexibility. On the other hand, it poses a tremendous logistic and energetic problem of transporting millions of molecules per second across the nuclear envelope, to facilitate their biological function in all compartments of the cell. Therefore, eukaryotes have evolved a molecular “nanomachine” known as the Nuclear Pore Complex (NPC). Embedded in the nuclear envelope, NPCs control and regulate all the bi-directional transport between the…

Collective amplitude mode fluctuations in a flat band superconductor formed at a semimetal surface

2016

We study the fluctuations of the amplitude (i.e., the Higgs-Anderson) mode in a superconducting system of coupled Dirac particles proposed as a model for possible surface or interface superconductivity in rhombohedral graphite. This system also serves as a generic model of a topological semimetal with an interaction-driven transition on its surface. We show that the absence of Fermi energy and vanishing of the excitation gap of the collective amplitude mode in the model leads to a large fluctuation contribution to thermodynamic quantities, such as the heat capacity. As a consequence, the mean-field theory becomes inaccurate, indicating that the interactions lead to a strongly correlated sta…

Sylviasta, Sylvialle, Sylviana : retoriikka ja merkityksenmuodostus osoitteessa www.sylviaplathforum.com

2016

This study explores the writings of Sylvia Plath Forum, a discussion forum in the Internet that was launched in 1998. Using Norman Fairclough’s critical discourse analysis, Chaïm Perelman’s theory of argumentation, Kenneth Burke’s idea of identification as the basis of rhetoric, and René Girards’s theory of mimetic desire as its framework this study looks into the forum’s meaning-making processes and the ways the author Sylvia Plath (1932-1963) and her readers are represented on the forum. Attention is paid especially to meaning-making practices that are connected with literary studies, feminism, medicalization, and cultic phenomena. Furthermore, cultic discourse and fan discourse are under…

Day-night differences in the sensitivity of adrenoceptors in the Syrian hamster pineal gland: an in vivo iontophoretic study.

1989

Abstract Investigations on the regulation of pineal melatonin synthesis in the Syrian hamster revealed distinct differences compared to this well-understood mechanism in rat. E.g., a circadian profile of pineal norepinephrine (NE) is absent, there is no β-adrenoceptor sensitivity during daytime and adrenergic receptor supersensitivity is not easily achieved. To elucidate the action of NE on pineal receptor sites, the effects of iontophoretic application of adrenergic compounds on spontaneous electrical discharge rates of pinealocytes were investigated during day- and nighttime. Following application of either NE, isoproterenol or clonidine, cells were activated, inhibited or not affected. W…

A muscarinic mechanism inhibiting the release of noradrenaline from peripheral adrenergic nerve fibres by nicotinic agents.

1968

Computational analysis of a multi-varied biomimetic neural network

2021

In recent years, astrocytes have emerged as such elements involved in inter-neuronal communication that they are increasingly considered in the synaptic coupling connecting neurons and synapses, thus constituting tripartite synapses. Many studies have focused on this astrocytic influence. With the description of the basic mechanisms of synapses, as well as the influence of gliotransmission, we emphasize that gliotransmission to extra-synaptic areas has so far been mainly studied in vivo and in vitro. We come closer to the paradigms used in AI, by proposing an analysis of the astrocyte influence on the variations of the parameters governing synaptic and extra-synaptic plasticity.We sought to…

Cartilage Repair and Regeneration: Focus on Multi-Disciplinary Strategies—Highlight on Magneto-Responsive Techniques

2021

This editorial focuses on the interesting studies published within the present Special Issue and dealing with the innovative multi-disciplinary therapeutic approaches for musculoskeletal diseases. Moreover, it highlights the noteworthy magneto-responsive technique for a cartilage regeneration scope and reports some interesting studies and their outcomes in this specific field.

A Regio- and Diastereoselective Anodic Aryl-Aryl Coupling in the Biomimetic Total Synthesis of (-)-Thebaine.

2018

The biosynthesis of thebaine is based on the regioselective, intramolecular, oxidative coupling of (R)-reticuline. For decades, chemists have sought to mimic this coupling by using stoichiometric oxidants. However, all approaches to date have suffered from low yields or the formation of undesired regioisomers. Electrochemistry would represent a sustainable alternative in this respect but all attempts to accomplish an electrochemical synthesis of thebaine have failed so far. Herein, a regio- and diastereoselective anodic coupling of 3',4',5'-trioxygenated laudanosine derivatives is presented, which finally enables electrochemical access to (-)-thebaine.

Biomimetic synthesis of the tumor-associated (2,3)-sialyl-T antigen and its incorporation into glycopeptide antigens from the mucins MUC1 and MUC4.

2004

Glycoproteins on epithelial tumor cells often exhibit aberrant glycosylation profiles. The incomplete formation of the glycan side chains resulting from a down-regulated glucosamine transfer and a premature sialylation results in additional peptide epitopes, which become accessible to the immune system in mucin-type glycoproteins. These cancer-specific structure alterations are considered to be a promising basis for selective immunological attack on tumor cells. Among the tumor-associated saccharide antigens, the (2,3)-sialyl-T antigen has been identified as the most abundant glycan, found in several different carcinoma cell lines. According to a linear biomimetic strategy, the (2,3)-sialyl…