A micro-bead device to explore Plasmodium falciparum-infected, spherocytic or aged red blood cells prone to mechanical retention by spleen endothelial slits

Présentation oraleInternational audiencen.

Activation-Induced Cytidine Deaminase (AID) Deficiency Causes the Autosomal Recessive Form of the Hyper-IgM Syndrome (HIGM2)

AbstractThe activation-induced cytidine deaminase (AID) gene, specifically expressed in germinal center B cells in mice, is a member of the cytidine deaminase family. We herein report mutations in the human counterpart of AID in patients with the autosomal recessive form of hyper-IgM syndrome (HIGM2). Three major abnormalities characterize AID deficiency: (1) the absence of immunoglobulin class switch recombination, (2) the lack of immunoglobulin somatic hypermutations, and (3) lymph node hyperplasia caused by the presence of giant germinal centers. The phenotype observed in HIGM2 patients (and in AID−/− mice) demonstrates the absolute requirement for AID in several crucial steps of B cell terminal differentiation necessary for efficient antibody responses

In situ measurement of rock compressibility in a heavy oil reservoir

International audienceCompaction drive is a potentially important recovery mechanism for weakly cemented heavy oil reservoirs. In order to assess its magnitude the knowledge of the compressibility of the reservoir sands is required. However, due to the very nature of this class of reservoirs, the reliability of laboratory measurements can be questioned as the specimens are heavily disturbed during the coring process. To circumvent this shortcoming, the option of carrying out in-situ compressibility measurements becomes attractive. The use of a dilatometer, allowing the downhole measurement of the pressure-deformation characteristics of the formation, has thus been considered. A preliminary study was carried out involving direct numerical simulations of a dilatometer test in a sand described by a Cam-Clay model. That study showed that the mechanical parameters, in particular the elastic and plastic compressibilities as well as the consolidation pressure do affect the response, thus establishing the theoretical feasibility of such a measurement. A series of three tests were conducted in a newly drilled well in an uncemented sandstone reservoir. By applying an inversion technique, based on an iterative finite element algorithm, it is then possible to identify the Cam-Clay parameters of the formation sands

Suivi thérapeutique pharmacologique de l’olanzapine

International audienc

Onset or exacerbation of cutaneous psoriasis during TNFalpha antagonist therapy.

International audienceThe widespread use of TNFalpha antagonists in recent years has led to the recognition of paradoxical adverse effects, defined as the onset or exacerbation of disorders that are usually improved by TNFalpha antagonists. Cutaneous psoriasis is an example, of which several cases have been reported. OBJECTIVE: To identify cases of psoriasis onset or exacerbation during TNFalpha antagonist therapy and to look for potential predictive factors. METHODS: We retrospectively reviewed cases of psoriasis onset or exacerbation during TNFalpha antagonist therapy. For each case we recorded the following data: age, sex, underlying disease, nature of the TNFalpha antagonist, effectiveness in improving the underlying disease, history of psoriasis in the patient or family, time to psoriasis development, type of psoriasis (confirmed by an experienced dermatologist), concomitant treatments, whether the TNFalpha antagonist was stopped or continued, and the outcome of the psoriasis. These data were compared to those in the literature. RESULTS: We identified 12 patients, six men and six women, with a mean age of 45.5 years. The TNFalpha antagonist was adalimumab in four patients, etanercept in six patients, and infliximab in two patients. The underlying disease was ankylosing spondylitis in six cases, rheumatoid arthritis in four, and psoriatic arthritis in two. Mean time from treatment initiation to psoriasis was 4.1 months (range, 1-15 months). A previous history of psoriasis in the patient was noted in six cases, including four of the six patients taking etanercept. TNFalpha antagonist therapy was effective on the underlying disease in 11 of the 12 patients. The drug was discontinued in five patients, of whom four experienced resolution of their psoriasis. In the remaining seven patients, the drug was continued and the skin lesions remained unchanged. Most of the patients had psoriasis vulgaris (plaque psoriasis); palmoplantar pustulosis was a feature in five patients. DISCUSSION: Over 40 cases of psoriasis onset or exacerbation during TNFalpha antagonist therapy have been reported in the literature. The prevalence of this adverse effect has been estimated at 1.5-5% of patients taking TNFalpha antagonists. The findings from our case series are consistent with data in the literature. Psoriasis is a class effect that has been reported with all the currently available TNFalpha antagonists. The skin lesions develop within the first few months of therapy. Patients with a wide range of underlying diseases can be affected. Palmoplantar pustulosis is a common feature. A previous history of psoriasis seems more common in patients who experience psoriasis onset or exacerbation during etanercept therapy (four of six patients in our study and 55% in the literature); thus, previous psoriasis may be a risk factor for psoriasis exacerbation during etanercept therapy

Quantification of void networks of as-sprayed and annealed nanostructured yttria-stabilized zirconia (YSZ) deposits manufactured by suspension plasma spraying

International audienceSuspension plasma spraying (SPS) allows processing a stabilized suspension of nanometer-sized feedstock particles to form thick (from 20 to 100 μm, average values) deposits. The void content and porous network of such deposits are difficult to quantify (in terms of void and size distributions, anisotropy, etc.) using conventional techniques due to their low resolution. The combination of ultra-small-angle X-ray scattering (USAXS) and helium pycnometry permits to address some of the characteristics of this void network. Deposits of yttria-partially stabilized zirconia (YSZ) were manufactured by plasma spraying a suspension made of solid sub-micrometer-sized particles (50 and 400 nm) with several sets of spray operating parameters. Results indicate that the average void size exhibits the same scale as the solid structure; i.e., nanometer sizes and multimodal size distribution which varies with spray operating parameters. About 90% of voids (by number) exhibit characteristic dimensions smaller than 40 nm. The cumulative void volume fraction of such as-sprayed deposits varies between about 13 and 20%, depending upon operating parameters. The void network architecture evolves also with annealing conditions: the void size distribution evolves toward higher void characteristic dimensions as a result of sintering of smallest voids but the cumulative void content does not decrease significantly

<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language:AR-SA" lang="EN-GB">Twenty-four-hour pattern in French firemen of lag time response to out-of-hospital cardiac arrest and work-related injury^#</span>

420-424Circadian cognitive and physical rhythms plus 24 h patterns of accidents and work-related injuries (WRI) have been verified in numerous studies. However, rarely, if ever, have 24 h temporal differences in both work performance and risk of WRI been assessed in the same group of workers. We explored in a homogenous group of French firemen (FM) 24 h patterns of both lag time (LT) response duration to emergency calls for medical help (ECFM) for life-threatening out-of-hospital cardiac arrests (OHCA), used as a non-specific index of work performance, and WRI. Our studies demonstrate rather high amplitude statistically significant 24 h patterns of the two variables. The LT response duration was twice as long ~0500 h (slowest response) than ~1600 h (fastest response). In the same group of FM, the actual number WRI/h was greatest ~1600 h and lowest in the early morning hours. However, the 24 h pattern of the relative risk (RR) of WRIs, i.e., per clock hour number of WRI/(total number of responses to emergency calls x number of FM at risk per response), was very different, the RR being greatest ~0200 h and lowest in the afternoon. The 24 h pattern in LT response duration to ECMH for OHCA and RR of WRI was strongly correlated (r=+0.85, P<0.01), with the nocturnal trough (slowest response) in LT response duration coinciding with the nocturnal peak RR of WRI. These findings indicate the requirement for circadian rhythm-based interventions to improve the nocturnal compromised work performance and elevated risk of WRI of shift-working FM. </span