Search results for "RESISTANCE"

Recurrences of multidrug-resistant tuberculosis: Strains involved, within-host diversity, and fine-tuned allocation of reinfections

2020

34 páginas, 13 figuras

Possible Mechanisms for Tumour Cell Sensitivity to TNF-a and Potential Therapeutic Applications

2001

TNF is a macrophage / monocyte-derived cytokine with cytostatic and cytotoxic anti-tumour activity. TNF-alpha can cause haemorrhagic necrosis and regression of experimental tumours. Nevertheless, the TNF-alpha doses required to cure tumour-bearing mice lead to injury of normal tissues and, eventually, may cause a lethal shock syndrome. This toxicity implies severe limitations for the therapeutic use of TNF-a. Reactive oxygen intermediates (ROIs) are involved in TNF-a-induced cell killing. Different studies are consistent with the hypothesis that tumour cell sensitivity to TNF-alpha is related to its capacity to buffer oxidative attack. Recently, we have demonstrated that the sensitivity of …

Death receptors as targets in cancer

2014

Anti-tumour therapies based on the use PARAs (pro-apoptotic receptor agonists), including TRAIL (TNF-Related Apoptosis inducing Ligand) or monoclonal antibodies targeting TRAIL-R1 or TRAIL-R2, have been disappointing so far, despite clear evidence of clinical activity and lack of adverse events for the vast majority of these compounds, whether combined or not with conventional or targeted anti-cancer therapies. This brief review aims at discussing the possible reasons for the lack of apparent success of these therapeutic approaches and at providing hints in order to rationally design optimal protocols based on our current understanding of TRAIL signalling regulation or resistance for future…

Nanosession: Spin Tunneling Systems

2013

SAMs Based Device Fabrication and Characterization

2015

Despite the high potentiality of SAMs for spintronics, not many results exist at the moment in the literature. This lack of results is mainly due to the difficulty to fabricate the devices. The two main technological problems consist in the ferromagnetic electrodes compatibility issues with wet chemistry and the short-circuit formation during top electrode deposition. A part of this thesis has been committed to overcome these technological problems. This chapter will explain the steps that led us to the development of SAMs-based magnetic tunnel nanojunctions.

Probing the electronic states of high-TMR off-stoichiometric Co2MnSi thin films by hard x-ray photoelectron spectroscopy

2014

The tunnel magnetoresistance ratio (TMR) of fully epitaxial magnetic tunnel junctions with an off-stoichiometric Co${}_{2}$MnSi Heusler alloy has been shown to exhibit a systematic dependence on Mn content, reaching 1135% at 4.2 K for Co${}_{2}$Mn${}_{1.29}$Si. In this paper, we explain the behavior of the observed TMR ratio using ab initio calculations and hard x-ray photoelectron spectroscopy (HAXPES). For the Mn-deficient samples, we show that the the drop of the TMR is caused by Co antisite atoms, which impose extra states into the minority-spin band gap. On the other hand, Mn-excess composition shows nearly half-metallic behavior. This result can be intuitively understood since both Co…

Introduction to Self-Assembled Monolayers

2015

One of the most exciting targets of molecular spintronics field is to go towards multifunctional devices where the properties can be accurately controlled and actively changed. Spin dependent hybridization at the metal/molecule interface could thus be used in the tailoring of the resistive and magnetoresistive response of spintronic devices exploiting chemistry versatility. In this new direction, Self-Assembled Monolayers (SAMs) appear as highly promising candidates since each part and function of this system can be modulated independently (like a molecular LEGO building unit). Despite highly promising, they are still scarcely investigated in the literature probably due to the difficulties …

Antiproliferative activity against leukemia cells of sesquiterpene lactones from the Turkish endemic plant Centaurea drabifolia subsp. detonsa

2017

The apolar organic extract obtained from aerial parts of Centaurea drabifolia Sibth. & Sm. subsp. detonsa (Bornm.) Wagenitz, growing wild in Turkey, was investigated for the first time for its secondary metabolite composition. Seven sesquiterpene lactones belonging to the guaiane class (1-7), including the new compound 4, along with a fatty acid lactone derivative (8), were isolated. The structures of these compounds were established by spectroscopic analysis, including 2D NMR spectroscopic techniques, with the stereostructure of the new guaiane 4 determined with the help of MTPA derivatization. Cytotoxic activities of compounds 1-7 were evaluated against two cancer cell lines, namely acute…

Resistance to change: a literature review and empirical study

2003

This paper examines organizational change, focusing on the distinction of changes according to their scope and presenting a typology of evolutionary and strategic changes. It also offers an in‐depth study of resistance to change. Through empirical research, the paper analyzes the importance of the sources of resistance to change defined theoretically, and considers both types of changes. The article shows which sources of resistance differ most, according to the scope of change, offering hints about where organizations should pay special attention when initiating a change process.

¿Qué creen? No soy chismoso pero…. Mexican gossip: Affiliation or self-interest?

2017

Whilst being taken more seriously, especially in anthropological and sociological studies, gossip is still often regarded trivial and of little academic research interest. Given that it is unstoppable, persistent and often enjoyable (Epstein, 2011), gossip has been examined in terms of function (e.g. talk about intimate matters to express shared values) and as a form of communication *for example, to express resistance (Goodman & Ben-Ze’ev, 1994). In this chapter, I examine the importance of gossip in the Mexican context. In Mexico, gossip has been examined in terms of function e.g. (Hagene, 2010), situation (Vázquez Garcia y Chávez Arellano, 2008) and resistance (Vázquez García 2007). …