261 research outputs found

    Waddlia chondrophila: from biology to pathogenicity.

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    Waddlia chondrophila is an emerging pathogen causing miscarriages in humans and abortions in ruminants. The full genome of this Chlamydia-related bacterium has been recently completed, providing new insights into its biology and evolution. Moreover, new cell biology approaches and the use of novel inhibitors have allowed detailed investigations of its interaction with host cells

    Functional genomics of intracellular bacteria.

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    During the genomic era, a large amount of whole-genome sequences accumulated, which identified many hypothetical proteins of unknown function. Rapidly, functional genomics, which is the research domain that assign a function to a given gene product, has thus been developed. Functional genomics of intracellular pathogenic bacteria exhibit specific peculiarities due to the fastidious growth of most of these intracellular micro-organisms, due to the close interaction with the host cell, due to the risk of contamination of experiments with host cell proteins and, for some strict intracellular bacteria such as Chlamydia, due to the absence of simple genetic system to manipulate the bacterial genome. To identify virulence factors of intracellular pathogenic bacteria, functional genomics often rely on bioinformatic analyses compared with model organisms such as Escherichia coli and Bacillus subtilis. The use of heterologous expression is another common approach. Given the intracellular lifestyle and the many effectors that are used by the intracellular bacteria to corrupt host cell functions, functional genomics is also often targeting the identification of new effectors such as those of the T4SS of Brucella and Legionella

    Big Tech Acquisitions and Innovation: An Empirical Assessment

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    In the past 20 years, large digital platforms have made many acquisitions, mainly young and innovative startups. Few of them have been reviewed by competition authorities and little is known on their evolution after acquisition. This paper intends to fill in this gap by looking at the development of the technologies owned by the acquired firms. We focus on technologies protected by a patent and we investigate whether an acquisition by a big tech contributes to their development. For this analysis, we use patent citations as a proxy for the innovation effort by the acquirer. Our main result is to show that acquisition increases the innovation effort of the acquirer but only temporarily. After 1.5 year, there is no longer a significant impact of the acquisition on the acquirer's innovation effort. This decline is relatively larger when the acquired patent belongs to a core technology field of the acquiring firm or to a large patent portfolio. On the contrary, citations by the rest of the industry are not negatively affected by acquisition, which does not corroborate the idea that the acquired technology has reached its maturity

    Non-epileptic seizures: delayed diagnosis in patients presenting with electroencephalographic (EEG) or clinical signs of epileptic seizures

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    AbstractThe clinical differentiation between epileptic seizures (ES) and non-epileptic seizures (NES) is often difficult and mostly based on the presence or absence of widely recognized features of ES such as tongue biting, falling, incontinence or concomitant epileptic abnormalities in the electroencephalogram (EEG). We retrospectively analysed the records of all patients referred to our Epilepsy Centre for refractory epilepsy and finally diagnosed with NES between 1980 and 1999 ( n= 103), half of them also exhibiting ES. The mean time-lapse between first attack and NES diagnosis was 8.7 ± 1.3 years and 16.5 ± 1.4 years for the NES and NES + ES groups respectively. At least one of the usual signs associated with generalized tonic–clonic seizures (tongue biting, falling or incontinence) was reported by 66% and 60% of patients with NES or NES + ES respectively. Interictal EEG abnormalities were recorded in 16% of NES patients vs. 80% of NES + ES patients. In the NES group, delay before establishing the correct diagnosis was significantly longer when the patients exhibited ≥1 symptom(s) of generalized seizures, or when patients exhibited interictal EEG abnormalities. Upon admission, 72% of NES patients and all NES + ES patients were being treated with antiepileptic drugs (AEDs).We conclude that EEG or clinical abnormalities suggestive of epileptic seizures are common in undiagnosed NES patients. Such diagnostic pitfalls, besides considerably delaying NES diagnosis, also considerably delay appropriate treatment implementation
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