Burned to the Bone

International audienc

Myelitis and tenosynovitis attributed to toxocariasis

International audienceNo abstrac

Effects of COVID-19 lockdown on low back pain intensity in chronic low back pain patients: results of the multicenter CONFI-LOMB study

Purpose: The COVID-19 pandemic and the extended lockdown are associated with numerous changes in behavior and lifestyles. The objective was to assess the impact of the first lockdown on LBP course among chronic LBP patients.Methods: Descriptive and analytical, cross-sectional, multicenter study, conducted by questionnaire from mid-May to end of June 2020 among patients treated for chronic LBP in 6 French and 1 Swiss center. Collected data concerned changes in LBP intensity during lockdown, lockdown experience, physical activity (PA) practice and sedentary lifestyle prior and during lockdown, recourse to care, consumption of psychoactive substances for LBP, and professional activity and its conditions during lockdown.Results: 360 participants (58.6% women, 52.1 ± 13.4 years) were included of which 65% were active (63% keep on working of which 54% teleworked). LBP got worse in 41.1%, mean VAS went from 49.5 ± 21.6 before to 53.5 ± 22.4 during lockdown (p Conclusion: These findings indicate that chronic LBP people suffered from increase in self-perceived LBP during lockdown and help to better understand the factors associated with their condition.</p

Role of dual-energy CT in the diagnosis and follow-up of gout: systematic analysis of the literature

International audienceThe aim of this systematic review was to determine the potential role of dual-energy CT in the diagnosis and follow-up of gout with regard to the Outcome Measures in Rheumatology (OMERACT) filter. A systematic analysis of the literature was conducted using the MEDLINE and Cochrane databases and published abstracts of international congresses, according to the criteria of the OMERACT filter: feasibility, reproducibility, validity versus laboratory (serum urate, MSU synovial fluid aspirate) and other imaging modalities for gout, and its sensitivity to change in patients on urate lowering therapy (ULT). Thirty-two articles were found representing a total of 1502 patients. The data on feasibility showed that the examination took little time and involved low levels of radiation but had current limited availability. Intra- and inter-observer reproducibility was excellent, with intra-class correlation coefficients > 0.9. Validity in comparison with polarized-light microscopy showed good sensitivity and specificity (> 80%). The diagnostic performance was better than that of radiography and conventional CT-scan and at least equivalent to that of ultrasonography. The sensitivity to change varied with effect sizes from 0.05 (low) to 1.24 (high) for decrease in the tophus volume following different ULT in gout patients. Dual-energy CT-scan is a reproducible and accurate imaging modality for the diagnosis of gout, particularly for tophaceous gout (intra- or extra-articular). It can become a second-line imaging modality of choice in cases of diagnostic doubt, such as ultrasonography. Its role remains uncertain in the follow-up of gout patients treated with ULT and needs further clarification

Structure-Based Analysis of the Interaction between the Simian Virus 40 T-Antigen Origin Binding Domain and Single-Stranded DNA▿ †

The origin-binding domain (OBD) of simian virus 40 (SV40) large T-antigen (T-Ag) is essential for many of T-Ag's interactions with DNA. Nevertheless, many important issues related to DNA binding, for example, how single-stranded DNA (ssDNA) transits along the T-Ag OBD, have yet to be established. Therefore, X-ray crystallography was used to determine the costructure of the T-Ag OBD bound to DNA substrates such as the single-stranded region of a forked oligonucleotide. A second structure of the T-Ag OBD crystallized in the presence of poly(dT)12 is also reported. To test the conclusions derived from these structures, residues identified as being involved in binding to ssDNA by crystallography or by an earlier nuclear magnetic resonance study were mutated, and their binding to DNA was characterized via fluorescence anisotropy. In addition, these mutations were introduced into full-length T-Ag, and these mutants were tested for their ability to support replication. When considered in terms of additional homology-based sequence alignments, our studies refine our understanding of how the T-Ag OBDs encoded by the polyomavirus family interact with ssDNA, a critical step during the initiation of DNA replication

Model for T-Antigen-Dependent Melting of the Simian Virus 40 Core Origin Based on Studies of the Interaction of the Beta-Hairpin with DNA▿

The interaction of simian virus 40 (SV40) T antigen (T-ag) with the viral origin has served as a model for studies of site-specific recognition of a eukaryotic replication origin and the mechanism of DNA unwinding. These studies have revealed that a motif termed the “beta-hairpin” is necessary for assembly of T-ag on the SV40 origin. Herein it is demonstrated that residues at the tip of the “beta-hairpin” are needed to melt the origin-flanking regions and that the T-ag helicase domain selectively assembles around one of the newly generated single strands in a manner that accounts for its 3′-to-5′ helicase activity. Furthermore, T-ags mutated at the tip of the “beta-hairpin” are defective for oligomerization on duplex DNA; however, they can assemble on hybrid duplex DNA or single-stranded DNA (ssDNA) substrates provided the strand containing the 3′ extension is present. Collectively, these experiments indicate that residues at the tip of the beta-hairpin generate ssDNA in the core origin and that the ssDNA is essential for subsequent oligomerization events