European telecommunications markets: International dynamics and implications for transforming economies

Today, the telecoms sector is not only one of the fastest growing sectors in the world but also one of the most rapidly changing sectors. In Western Europe different strategies under different regulatory frameworks are being pursued in the effort to meet the challenges posed by this. In Central and Eastern Europe, telecommunications networks are still extremely underdeveloped. What lessons can the transforming economies draw from the experiences of Western European countries

Current Understanding of Biomarkers in Post Traumatic Stress Disorder and Mild Traumatic Brain Injury: A Systematic Review and Implications for Research and Treatment

For nearly 100 years, it was erroneously believed that the loss of consciousness and/or the altered mental status associated with a mild traumatic brain injury (mTBI) offered protection from the development of posttraumatic stress disorder (PTSD). However, it is now accepted that it is possible for PTSD to result from mTBI, and that the co-occurrence of these two conditions creates a more difficult condition to treat and worsens prognosis. In addition, it is known that the symptomology associated with PTSD and mTBI have a great deal of overlap, complicating diagnoses. The objective of this chapter is to review the current state of biomarkers aimed at diagnosing comorbid mTBI and PTSD that are useful on a single-patient basis and are not reliant on self-report or arduous interviews. Further, implications for future research and treatment are discussed

Tobacco plastid ribosomal protein S18 is essential for cell survival

Plastid genomes contain a conserved set of genes most of which are involved in either photosynthesis or gene expression. Among the ribosomal protein genes present in higher plant plastid genomes, rps18 is special in that it is absent from the plastid genomes of several non-green unicellular organisms, including Euglena longa and Toxoplasma gondii. Here we have tested whether the ribosomal protein S18 is required for translation by deleting the rps18 gene from the tobacco plastid genome. We report that, while deletion of the rps18 gene was readily obtained, no homoplasmic Δrps18 plants or leaf sectors could be isolated. Instead, segregation into homoplasmy led to severe defects in leaf development suggesting that the knockout of rps18 is lethal and the S18 protein is required for cell survival. Our data demonstrate that S18 is indispensable for plastid ribosome function in tobacco and support an essential role for plastid translation in plant development. Moreover, we demonstrate the occurrence of flip-flop recombination on short inverted repeat sequences which generates different isoforms of the transformed plastid genome that differ in the orientation a 70 kb segment in the large single-copy region. However, infrequent occurrence of flip-flop recombination and random segregation of plastid genomes result in the predominant presence of only one of the isoforms in many tissue samples. Implications for the interpretation of chloroplast transformation experiments and vector design are discussed

Reconstructing the evolution of the mitochondrial ribosomal proteome

For production of proteins that are encoded by the mitochondrial genome, mitochondria rely on their own mitochondrial translation system, with the mitoribosome as its central component. Using extensive homology searches, we have reconstructed the evolutionary history of the mitoribosomal proteome that is encoded by a diverse subset of eukaryotic genomes, revealing an ancestral ribosome of alpha-proteobacterial descent that more than doubled its protein content in most eukaryotic lineages. We observe large variations in the protein content of mitoribosomes between different eukaryotes, with mammalian mitoribosomes sharing only 74 and 43% of its proteins with yeast and Leishmania mitoribosomes, respectively. We detected many previously unidentified mitochondrial ribosomal proteins (MRPs) and found that several have increased in size compared to their bacterial ancestral counterparts by addition of functional domains. Several new MRPs have originated via duplication of existing MRPs as well as by recruitment from outside of the mitoribosomal proteome. Using sensitive profile–profile homology searches, we found hitherto undetected homology between bacterial and eukaryotic ribosomal proteins, as well as between fungal and mammalian ribosomal proteins, detecting two novel human MRPs. These newly detected MRPs constitute, along with evolutionary conserved MRPs, excellent new screening targets for human patients with unresolved mitochondrial oxidative phosphorylation disorders

Cross‐border expansion and competitive interactions of indigenous mobile network operators in sub‐Saharan Africa

Emerging‐market multinational enterprises (EMNEs) have become major players in the global economy, with an increasing share of global foreign direct investment (FDI). Indigenous mobile network operators (MNOs) in sub‐Saharan Africa (SSA) are not left out in this pursuit, as they seek growth and competitiveness beyond their domestic markets. We investigate the FDI location choices and competitive interactions of the five indigenous SSA MNOs that had internationalized as of 2014 and find that, contrary to the literature, these EMNEs, operating in a key and rapidly developing industry, did not tend to commence their cross‐border expansion in geographically close markets. In addition, the MNOs are more likely to invest in countries with stronger control over corruption and do not appear to engage in heavy head‐to‐head competition with their rivals. These findings contribute to the internationalization literature in the context of the investment and competitive behaviors of the currently underexplored indigenous SSA multinationals

Mitoriboscins : mitochondrial-based therapeutics targeting cancer stem cells (CSCs), bacteria and pathogenic yeast

The “endo-symbiotic theory of mitochondrial evolution” states that mitochondrial organelles evolved from engulfed aerobic bacteria, after millions of years of symbiosis and adaptation. Here, we have exploited this premise to design new antibiotics and novel anti-cancer therapies, using a convergent approach. First, virtual high-throughput screening (vHTS) and computational chemistry were used to identify novel compounds binding to the 3D structure of the mammalian mitochondrial ribosome. The resulting library of ~880 compounds was then subjected to phenotypic drug screening on human cancer cells, to identify which compounds functionally induce ATP-depletion, which is characteristic of mitochondrial inhibition. Notably, the top ten “hit” compounds define four new classes of mitochondrial inhibitors. Next, we further validated that these novel mitochondrial inhibitors metabolically target mitochondrial respiration in cancer cells and effectively inhibit the propagation of cancer stem-like cells in vitro. Finally, we show that these mitochondrial inhibitors possess broad-spectrum antibiotic activity, preventing the growth of both gram-positive and gram-negative bacteria, as well as C. albicans – a pathogenic yeast. Remarkably, these novel antibiotics also were effective against methicillin-resistant Staphylococcus aureus (MRSA). Thus, this simple, yet systematic, approach to the discovery of mitochondrial ribosome inhibitors could provide a plethora of anti-microbials and anti-cancer therapies, to target drug-resistance that is characteristic of both i) tumor recurrence and ii) infectious disease. In summary, we have successfully used vHTS combined with phenotypic drug screening of human cancer cells to identify several new classes of broad-spectrum antibiotics that target both bacteria and pathogenic yeast. We propose the new term “mitoriboscins” to describe these novel mitochondrial-related antibiotics. Thus far, we have identified four different classes of mitoriboscins, such as: 1) mitoribocyclines, 2) mitoribomycins, 3) mitoribosporins and 4) mitoribofloxins. However, we broadly define mitoriboscins as any small molecule(s) or peptide(s) that bind to the mitoribosome (large or small subunits) and, as a consequence, inhibit mitochondrial function, i.e., mitoribosome inhibitors