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971.
Altenhöfer S Kleikers PW Radermacher KA Scheurer P Rob Hermans JJ Schiffers P Ho H Wingler K Schmidt HH 《Cellular and molecular life sciences : CMLS》2012,69(14):2327-2343
Reactive oxygen species (ROS) are cellular signals but also disease triggers; their relative excess (oxidative stress) or shortage (reductive stress) compared to reducing equivalents are potentially deleterious. This may explain why antioxidants fail to combat diseases that correlate with oxidative stress. Instead, targeting of disease-relevant enzymatic ROS sources that leaves physiological ROS signaling unaffected may be more beneficial. NADPH oxidases are the only known enzyme family with the sole function to produce ROS. Of the catalytic NADPH oxidase subunits (NOX), NOX4 is the most widely distributed isoform. We provide here a critical review of the currently available experimental tools to assess the role of NOX and especially NOX4, i.e. knock-out mice, siRNAs, antibodies, and pharmacological inhibitors. We then focus on the characterization of the small molecule NADPH oxidase inhibitor, VAS2870, in vitro and in vivo, its specificity, selectivity, and possible mechanism of action. Finally, we discuss the validation of NOX4 as a potential therapeutic target for indications including stroke, heart failure, and fibrosis. 相似文献
972.
Galvin P Thompson D Ryan KB McCarthy A Moore AC Burke CS Dyson M Maccraith BD Gun'ko YK Byrne MT Volkov Y Keely C Keehan E Howe M Duffy C MacLoughlin R 《Cellular and molecular life sciences : CMLS》2012,69(3):389-404
Nanoparticles (NPs) comprised of nanoengineered complexes are providing new opportunities for enabling targeted delivery of a range of therapeutics and combinations. A range of functionalities can be included within a nanoparticle complex, including surface chemistry that allows attachment of cell-specific ligands for targeted delivery, surface coatings to increase circulation times for enhanced bioavailability, specific materials on the surface or in the nanoparticle core that enable storage of a therapeutic cargo until the target site is reached, and materials sensitive to local or remote actuation cues that allow controlled delivery of therapeutics to the target cells. However, despite the potential benefits of NPs as smart drug delivery and diagnostic systems, much research is still required to evaluate potential toxicity issues related to the chemical properties of NP materials, as well as their size and shape. The need to validate each NP for safety and efficacy with each therapeutic compound or combination of therapeutics is an enormous challenge, which forces industry to focus mainly on those nanoparticle materials where data on safety and efficacy already exists, i.e., predominantly polymer NPs. However, the enhanced functionality affordable by inclusion of metallic materials as part of nanoengineered particles provides a wealth of new opportunity for innovation and new, more effective, and safer therapeutics for applications such as cancer and cardiovascular diseases, which require selective targeting of the therapeutic to maximize effectiveness while avoiding adverse effects on non-target tissues. 相似文献
973.
Age is an important risk for autoimmunity, and many autoimmune diseases preferentially occur in the second half of adulthood
when immune competence has declined and thymic T cell generation has ceased. Many tolerance checkpoints have to fail for an
autoimmune disease to develop, and several of those are susceptible to the immune aging process. Homeostatic T cell proliferation
which is mainly responsible for T cell replenishment during adulthood can lead to the selection of T cells with increased
affinity to self- or neoantigens and enhanced growth and survival properties. These cells can acquire a memory-like phenotype,
in particular under lymphopenic conditions. Accumulation of end-differentiated effector T cells, either specific for self-antigen
or for latent viruses, have a low activation threshold due to the expression of signaling and regulatory molecules and generate
an inflammatory environment with their ability to be cytotoxic and to produce excessive amounts of cytokines and thereby inducing
or amplifying autoimmune responses. 相似文献
974.
Over the last two decades the molecular and cellular mechanisms underlying T cell activation, expansion, differentiation,
and memory formation have been intensively investigated. These studies revealed that the generation of memory T cells is critically
impacted by a number of factors, including the magnitude of the inflammatory response and cytokine production, the type of
dendritic cell [DC] that presents the pathogen derived antigen, their maturation status, and the concomitant provision of
costimulation. Nevertheless, the primary stimulus leading to T cell activation is generated through the T cell receptor [TCR]
following its engagement with a peptide MHC ligand [pMHC]. The purpose of this review is to highlight classical and recent
findings on how antigen recognition, the degree of TCR stimulation, and intracellular signal transduction pathways impact
the formation of effector and memory T cells. 相似文献
975.
976.
977.
Machnicka B Grochowalska R Bogusławska DM Sikorski AF Lecomte MC 《Cellular and molecular life sciences : CMLS》2012,69(2):191-201
This review focuses on the recent advances in functions of spectrins in non-erythroid cells. We discuss new data concerning
the commonly known role of the spectrin-based skeleton in control of membrane organization, stability and shape, and tethering
protein mosaics to the cellular motors and to all major filament systems. Particular effort has been undertaken to highlight
recent advances linking spectrin to cell signaling phenomena and its participation in signal transduction pathways in many
cell types. 相似文献
978.
Xue B Mizianty MJ Kurgan L Uversky VN 《Cellular and molecular life sciences : CMLS》2012,69(8):1211-1259
Many proteins and protein regions are disordered in their native, biologically active states. These proteins/regions are abundant
in different organisms and carry out important biological functions that complement the functional repertoire of ordered proteins.
Viruses, with their highly compact genomes, small proteomes, and high adaptability for fast change in their biological and
physical environment utilize many of the advantages of intrinsic disorder. In fact, viral proteins are generally rich in intrinsic
disorder, and intrinsically disordered regions are commonly used by viruses to invade the host organisms, to hijack various
host systems, and to help viruses in accommodation to their hostile habitats and to manage their economic usage of genetic
material. In this review, we focus on the structural peculiarities of HIV-1 proteins, on the abundance of intrinsic disorder
in viral proteins, and on the role of intrinsic disorder in their functions. 相似文献
979.
980.
Arboleda VA Lee H Parnaik R Fleming A Banerjee A Ferraz-de-Souza B Délot EC Rodriguez-Fernandez IA Braslavsky D Bergadá I Dell'Angelica EC Nelson SF Martinez-Agosto JA Achermann JC Vilain E 《Nature genetics》2012,44(7):788-792
IMAGe syndrome (intrauterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenita and genital anomalies) is an undergrowth developmental disorder with life-threatening consequences. An identity-by-descent analysis in a family with IMAGe syndrome identified a 17.2-Mb locus on chromosome 11p15 that segregated in the affected family members. Targeted exon array capture of the disease locus, followed by high-throughput genomic sequencing and validation by dideoxy sequencing, identified missense mutations in the imprinted gene CDKN1C (also known as P57KIP2) in two familial and four unrelated patients. A familial analysis showed an imprinted mode of inheritance in which only maternal transmission of the mutation resulted in IMAGe syndrome. CDKN1C inhibits cell-cycle progression, and we found that targeted expression of IMAGe-associated CDKN1C mutations in Drosophila caused severe eye growth defects compared to wild-type CDKN1C, suggesting a gain-of-function mechanism. All IMAGe-associated mutations clustered in the PCNA-binding domain of CDKN1C and resulted in loss of PCNA binding, distinguishing them from the mutations of CDKN1C that cause Beckwith-Wiedemann syndrome, an overgrowth syndrome. 相似文献