17 research outputs found

    Genome-wide Analysis of the Host Intracellular Network that Regulates Survival of Mycobacterium tuberculosis

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    SummaryWe performed a genome-wide siRNA screen to identify host factors that regulated pathogen load in human macrophages infected with a virulent strain of Mycobacterium tuberculosis. Iterative rounds of confirmation, followed by validation, identified 275 such molecules that were all found to functionally associate with each other through a dense network of interactions. This network then yielded to a molecular description of the host cell functional modules that were both engaged and perturbed by the pathogen. Importantly, a subscreen against a panel of field isolates revealed that the molecular composition of the host interface varied with both genotype and the phenotypic properties of the pathogen. An analysis of these differences, however, permitted identification of those host factors that were invariantly involved, regardless of the diversification in adaptive mechanisms employed by the pathogen. Interestingly, these factors were found to predominantly function through the regulation of autophagy

    Identification of Host-Dependent Survival Factors for Intracellular Mycobacterium tuberculosis through an siRNA Screen

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    The stable infection of host macrophages by Mycobacterium tuberculosis (Mtb) involves, and depends on, the attenuation of the diverse microbicidal responses mounted by the host cell. This is primarily achieved through targeted perturbations of the host cellular signaling machinery. Therefore, in view of the dependency of the pathogen on host molecules for its intracellular survival, we wanted to test whether targeting such factors could provide an alternate route for the therapeutic management of tuberculosis. To first identify components of the host signaling machinery that regulate intracellular survival of Mtb, we performed an siRNA screen against all known kinases and phosphatases in murine macrophages infected with the virulent strain, H37Rv. Several validated targets could be identified by this method where silencing led either to a significant decrease, or enhancement in the intracellular mycobacterial load. To further resolve the functional relevance of these targets, we also screened against these identified targets in cells infected with different strains of multiple drug-resistant mycobacteria which differed in terms of their intracellular growth properties. The results obtained subsequently allowed us to filter the core set of host regulatory molecules that functioned independently of the phenotypic variations exhibited by the pathogen. Then, using a combination of both in vitro and in vivo experimentation, we could demonstrate that at least some of these host factors provide attractive targets for anti-TB drug development. These results provide a “proof-of-concept” demonstration that targeting host factors subverted by intracellular Mtb provides an attractive and feasible strategy for the development of anti-tuberculosis drugs. Importantly, our findings also emphasize the advantage of such an approach by establishing its equal applicability to infections with Mtb strains exhibiting a range of phenotypic diversifications, including multiple drug-resistance. Thus the host factors identified here may potentially be exploited for the development of anti-tuberculosis drugs

    Abstracts from the 3rd International Genomic Medicine Conference (3rd IGMC 2015)

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    Life cycle assessment of asphalt pavement maintenance and rehabilitation techniques: a study for the City of St. John’s

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    Although pavement maintenance and rehabilitation (M&R) techniques are usually examined in economic terms, there is a growing need to address their environmental footprints. The objective of this study is to assess the environmental impacts of M&R techniques. Life cycle assessment (LCA) can help in the decision-making process of selecting suitable maintenance techniques based on their environmental impacts. This study investigates: patching, rout & sealing, hot in-place recycling, and cold in-place recycling. Global warming potential (GWP), acidification potential, human health particulate, eutrophication potential, ozone depletion potential, and smog potential are estimated as environmental impacts for each maintenance activity. Materials, equipment use (for construction and M&R), and transportation were the main elements considered. A sensitivity test is performed to identify the significant factors for the LCA. The study concluded that GWP was the most important impact category. Rout & sealing and cold in-place recycling produced the lowest GWP emissions. Notably, pavement patching and hot in-place recycling showed significant detrimental environmental impacts.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    Aplikasi asas bolasepak untuk kanak-kanak bagi pelantar android

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    Bolasepak merupakan antara sukan yang paling popular di Malaysia dan di seluruh dunia. Kanak-kanak juga tidak terkecuali meminati bolasepak. Selain itu kanak-kanak juga amat tertarik dengan aplikasi permainan di telefon pintar. Namun begitu, aplikasi yang mengajar kanak-kanak bermain bola sepak masih kurang dibangunkan di Malaysia. Oleh yang demikian, aplikasi ini dibangunkan. Aplikasi Asas Bolasepak Untuk Kanak-kanak Bagi Pelantar Android merupakan satu sistem berasaskan telefon pintar Android yang berfungsi sebagai alternatif kepada pembelajaran bermain bolasepak. Objektif pembangunan aplikasi ini adalah untuk mendidik kanak-kanak tentang cara-cara bermain bolasepak dengan betul. Model ADDIE diimplementasikan sebagai metodologi pembangunan aplikasi ini. Keputusan daripada pengujian terhadap pengguna sasaran menunjukkan 80% responden bersetuju aplikasi ini membantu meningkatkan pemahaman mereka tentang asas sukan bolasepak. Kesimpulannya, aplikasi ini telah berjaya mencapai objektif pembangunan serta berjaya memenuhi kehendak pengguna sasaran

    Nanoarchitectonics: a new materials horizon for Prussian blue and its analogues

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    Although porous materials based on coordination compounds, including metal-organic frameworks (MOFs) and porous coordination polymers (PCPs), have well-defined pore structures and promising properties, they can efficiently be prepared by conventional and facile methods. Among coordination compounds, Prussian blue (PB) and its analogues (PBA) show high physical/chemical properties and potential as a multifunctional platform for various applications such as information records, sensing, batteries, biomedicine, imaging, and water purification. This review introduces versatile paths for nano-and meso-structural controls and demonstrates strong relationship between nanoarchitectures and properties with regard to PB and PBAs. This review will provide some guidance for future derivations of nanoarchitectonics based on coordination compounds which are PB and PBA
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