858 research outputs found

    Analysis and characterization of mouse monoclonal antibodies reactive to Chikungunya virus (CHIKV)

    Get PDF
    occurring in 1984). However, plague has made an astonishing comeback in the last decade. Methods: n/a. Results: After a silence of 50 years, an outbreak of bubonic plague suddenly occurred close to Oran in Algeria, in June 2003. Eighteen bubonic cases were identified, and Yersinia pestis was isolated from 6 patients. In July 2008, a new cluster was reported among nomads 300 km south of the first one. Four members of one family were affected and one died. The bacillus was isolated from one patient. No epidemiological association was identified between the two events. On June 2009, 25 years after the last occurrence in the country, Libya reported five confirmed cases of bubonic plague in the Tobruk area. Y. pestis was isolated from three patients. In all these cases, further local ecological investigations confirmed the existence of a natural focus The re-emergence of human plague in the region is not without international consequences. Two of the last concerned natural foci are close to an international port which raises the question of the potential exportation of infected rodents. Cross-border tensions, between ''plague countries'' and ''plague-free countries'' have been observed although the foci's limits are unknown as any systematic ecological investigation and surveillance is lacking. Additionally, the potential weaponization of Y.pestis together with international political tensions feed a recurrent interest in plague in North Africa. False rumors of alleged military laboratory accidents or terrorist acts are routinely mentioned, although events could be first explained by the natural history of the disease. Conclusion: In this context, and although the number of human cases has been very limited so far, the first priorities are to establish appropriate ecological surveillance and agree on a common plague control strategy for the region

    Computational Analysis of a Radiofrequency Knee Coil for Low-Field MRI Using FDTD

    Get PDF
    Magnetic resonance imaging (MRI) is essential for the diagnosis and treatment of musculoskeletal conditions. Low-field (< 0.5T) imaging is a cost-effective alternative to more expensive high-field strength imaging due to the inexpensive setting, greater patient comfort and better safety profile. On the other hand, if compared with high-field body scanners, the low-field scanners produce poor-quality images with lower signal-to-noise ratio. Especially in low-field MR, receiver coil performance plays a significant role in image quality. Coil performance is generally evaluated using classical electromagnetic theory, but when the coil is loaded with a sample, an analytical solution is extremely difficult to derive, so that a trial-and-error approach is often followed. Numerical methods have been proposed in literature as good alternatives to predict MRI coil performance. In this study the performance of a knee coil for low-field (0.5 T) MR scanners is analyzed using workbench tests and numerical simulation with a software program based on the finite difference time domain method. Parameter performances measured using the classical workbench test are compared with those obtained using numerical simulations. Finally, the knee coil performance is validated with images acquired in a commercial low-field MR system. RI Positano, Vincenzo/A-6953-2008 OI Positano, Vincenzo/0000-0001-6955-957

    Imported cases of Chikungunya and Dengue fever in Emilia Romagna region, Italy

    Get PDF
    Imported cases of Chikungunya and Dengue fever in Emilia Romagna region, Italy F. Cavrini 1,∗, P. Gaibani2, C. Manisera3, A. Pierro4, G. Rossini 5, M.P. Landini 5, V. Sambri6 1 S. Orsola-Malpighi Hospital, BOLOGNA, Italy 2 S.Orsola-Malpighi Hospital, Section of Microbiology, BOLOGNA, Italy 3 S.Orsola-Malpighi Hospital, Section of Microbiology, BOLOGNA, Italy 4 S.Orsola-Malpighi, Bologna, Italy 5 S.Orsola-Malpighi Hospital, section of Microbiology, BOLOGNA, Italy 6 University of Bologna, Bologna, Ital

    Comparative genomic and phylogenetic analysis of the first usutu virus isolate from a human patient presenting with neurological symptoms.

    Get PDF
    Usutu virus (USUV) is a mosquito-borne flavivirus, belonging to the Japanese encephalitis antigenic complex, that circulates among mosquitoes and birds. We describe and analyze the complete genome sequence of the first USUV strain isolated from an immunocompromised patient with neuroinvasive disease. This USUV isolate showed an overall nucleotide identity of 99% and 96%, respectively, with the genomes of isolates from Europe and Africa. Comparison of the human USUV complete polyprotein sequence with bird-derived strains, showed two unique amino acid substitutions. In particular, one substitution (S595G) was situated in the DIII domain of the viral Envelope protein that is recognized by flavivirus neutralizing antibodies. An additional amino acid substitution (D3425E) was identified in the RNA-dependent RNA polymerase (RdRp) domain of the NS5 protein. This substitution is remarkable since E3425 is highly conserved among the other USUV isolates that were not associated with human infection. However, a similar substitution was observed in Japanese encephalitis and in West Nile viruses isolated from humans. Phylogenetic analysis of the human USUV strain revealed a close relationship with an Italian strain isolated in 2009. Analysis of synonymous nucleotide substitutions (SNSs) among the different USUV genomes showed a specific evolutionary divergence among different countries. In addition, 15 SNSs were identified as unique in the human isolate. We also identified four specific nucleotide substitutions in the 59 and 39 untranslated regions (UTRs) in the human isolate that were not present in the other USUV sequences. Our analyses provide the basis for further experimental studies aimed at defining the effective role of these mutations in the USUV genome, their potential role in the development of viral variants pathogenic for humans and their evolution and dispersal out of Africa

    Serological update of the Chikungunya epidemic outbreak in Italy

    Get PDF
    Serological update of the Chikungunya epidemic outbreak in Italy P. Gaibani1,∗, A. Pierro1, F. CAVRINI2, G. Rossini 3, M.P. Landini 3, C. Manisera4, V. Sambri5 1 S.Orsola-Malpighi, Bologna, Italy 2 S. Orsola-Malpighi Hospital, BOLOGNA, Italy 3 S.Orsola-Malpighi Hospital, section of Microbiology, BOLOGNA, Italy 4 S.Orsola-Malpighi Hospital, Microbiology, Bologna, Italy 5 University of Bologna, Bologna, Ital

    Design, simulation, and fabrication of a three-dimensional printed pump mimicking the left ventricle motion

    Get PDF
    The development of accurate replicas of the circulatory and cardiac system is fundamental for a deeper understanding of cardiovascular diseases and the testing of new devices. Although numerous works concerning mock circulatory loops are present in the current state of the art, still some limitations are present. In particular, a pumping system able to reproduce the left ventricle motion and completely compatible with the magnetic resonance environment to permit the four-dimensional flow monitoring is still missing. The aim of this work was to evaluate the feasibility of an actuator suitable for cardiovascular mock circuits. Particular attention was given to the ability to mimic the left ventricle dynamics including both compression and twisting with the magnetic resonance compatibility. In our study, a left ventricle model to be actuated through vacuum was designed. The realization of the system was evaluated with finite element analysis of different design solutions. After the in silico evaluation phase, the most suitable design in terms of physiological values reproduction was fabricated through three-dimensional printing for in vitro validation. A pneumatic experimental setup was developed to evaluate the pump performances in terms of actuation, in particular ventricle radial and longitudinal displacement, twist rotation, and ejection fraction. The study demonstrated the feasibility of a custom pneumatic pump for mock circulatory loops able to reproduce the physiological ventricle movement and completely suitable for the magnetic resonance environment
    • …
    corecore