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De nombreuses équipes travaillent sur la perfusion ex vivo des transplants rénaux et la prolongation de la durée de préservation afin de permettre le transport des transplants rénaux sur de longues distances, d’évaluer leur viabilité et permettre le développement de thérapies innovantes dans la pratique clinique.

The aim of this single-center crossover substudy was to assess pharmacokinetics and pharmacodynamics [inosine 5′-monophosphate dehydrogenase (IMPDH) activity] of enteric-coated mycophenolate sodium (EC-MPS) and mycophenolate mofetil (MMF) at steady-state conditions. Stable maintenance renal transplant patients on 1 g MMF b.i.d. participating in a double-blind, multicenter study, were randomized to receive EC-MPS (720 mg b.i.d.) or continue receiving MMF (1000 mg b.i.d.) for 12 months. Thereafter, all patients (n = 18) received 720 mg EC-MPS b.i.d. Area under the plasma mycophenolic acid (MPA) concentration–time curve with EC-MPS (57.4 ± 15.0 μg h/mL) fulfilled bioequivalence criteria (geometric mean 0.98 (90% CI: 0.87–1.11) compared to MMF (58.4 ± 14.1 μg h/mL). Consistent with the delayed release characteristics of EC-MPS, peak MPA concentration (geometric mean 0.89; 90% CI: 0.70–1.13) occurred approximately 0.5 h later (p < 0.05) and predose MPA levels (geometric mean 2.10; 90% CI: 1.51–2.91) were higher and more variable, not fulfilling bioequivalence criteria. IMPDH activity inversely followed MPA concentrations and was inhibited to a similar degree (approximately 85%) by both formulations. The calculated value for 50% IMPDH inhibition was identical for both drugs. In conclusion, equimolar doses of EC-MPS and MMF produce equivalent MPA exposure, while the delayed release formulation of EC-MPS exhibits more variable predose levels and TmaxOverall, IMPDH activity reflected MPA pharmacokinetics.

Purpose : A method is presented for visualizing microcalcifications by full-field mammography using wavelet frames, an enhancement operator, and a suitable reconstruction technique. Material and methods : The computer algorithm is tested on 24 digital mammographies (Senographe 2000D, GE Medical Systems) containing microcalcifications. This algorithm highlights microcalcification-like structures by means of a filter bank that is based on wavelet decomposition. What is new about this filter bank is that the discretization of the continuous wavelet transformation is specifically adjusted to the problem of image analysis, allowing for a better discrimination of microcalcifications from the image background. Results : In all cases (24/24), microcalcifications were depicted with a markedly higher contrast. Conclusion : Special computer algorithms improve the visualization of microcalcifications. This means in principle, that there is a potential to improve diagnostic assessment.

The geometry of airborne reflectance measurements above broken cloud fields is simulated for various flight levels, artificial and natural cloud distributions with a simple ray-tracing technique. A similarity relation, which uses the cloud structure within the field of view of the pyranometer below the aircraft, could be derived to extrapolate from these airborne samples to averages over larger areas, which for instance are covered by several pixels of satellite measurements. The data probes were obtained during the first flight of the metric camera (MOMS-O1) in the “Shuttle Pallet Satellite”. The application of this method in field experiments requires areal overviews (photographs from aircraft or satellites) of the experiment site to be sampled from aircraft.

Allograft infiltration has been described in up to 20% of all patients with posttransplant lymphoproliferative disorder (PTLD), most representing EBV-positive B-cell lymphomas. Plasma cells are often observed in humoral rejection biopsies, but graft infiltration by plasmacytoma-like PTLD is rare. We report the case of a 54-year-old simultaneous pancreas-kidney transplant recipient (immunosuppression: OKT3, methylprednisolone, cyclosporine, and azathioprine), diagnosed with an IgG-kappa monoclonal gammopathy of undetermined significance eighteen years after transplant. Nine months later, pancreas allograft biopsy performed due to new-onset hyperglycemia (HgA1C 8.6%, C-peptide 6.15ng/mL and anti-GAD 0.9UI/mL) revealed a monotypic plasma cell infiltrate, CD19, CD79a, CD138 positive, with IgG-kappa light chain restriction, and EBV negative. PET-scan FDG uptake was limited to pancreas allograft. Tumor origin could not be established (using DNA microsatellite analysis). Despite treatment with bortezomib and dexamethasone, patient eventually died one month later. This is the first report of a late onset extramedullary plasmacytoma involving a pancreas allograft.

Infections are among the most common complications transplant physicians face when dealing with solid organ transplant recipients. We present a case of pyomyositis caused by Staphylococcus aureus in a patient with IgA nephropathy and a kidney transplant, under treatment with mTOR inhibitors and prednisone. This entity is a rare intramuscular infection, given the resistance of healthy muscle to colonization. We review the most frequent agents, the diagnostic algorithm, and therapeutic alternatives. We also comment on the role of mTOR inhibitors in this case as possible predisposing factor for the infection.