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Background Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP), a rare disorder affecting young adults, causes gradual weakness of the limbs, areflexia and impaired sensory function. New CIDP phenotypes without pathogenic antibodies but with modified cell profiles have been described. Treatments include corticotherapy, intravenous immunoglobulins, and plasmapheresis but the latter’s action mechanisms remain unclear. Plasmapheresis supposedly removes toxic agents like antibodies from plasma but it is uncertain whether it has an immune-modulating effect. Also, the refining mechanisms of the two main plasmapheresis techniques—single plasma exchange and double filtration plasmapheresis (DFPP) – are different and unclear. This study aims to compare the evolution of peripheral lymphocyte profiles in patients with CIDP according to their treatment (single centrifugation plasmapheresis or DFPP) to better grasp the action mechanisms of both techniques. Method In this proof-of-concept, monocentric, prospective, Single-Case Experimental Design study, 5 patients are evaluated by alternating their treatment type (single plasma exchange or DFPP) for 6 courses of treatment after randomization to their first treatment type. Each course of treatment lasts 2–4 weeks. For single plasma exchange, 60 ml/kg plasma will be removed from the patient and replaced with albumin solutes, with a centrifugation method to avoid the immunological reaction caused by the membrane used with the filtration method. For DFPP, 60 ml/kg plasma will be removed from the patient with a plasma separator membrane, then processed via a fractionator membrane to remove molecules of a greater size than albumin before returning it to the patient. This technique requires no substitution solutes, only 20 g of albumin to replace what would normally be lost during a session. The primary outcome is the difference between the two plasmapheresis techniques in the variation of the TH1/TH17 ratio over the period D0H0-D0H3 and D0H0-D7. Secondary outcomes include the variation in lymphocyte subpopulations at each session and between therapeutic plasmapheresis techniques, the clinical evolution, tolerance and cost of treatments. Discussion Understanding the action mechanisms of single plasma exchange and DFPP will help us to offer the right treatment to each patient with CIPD according to efficacy, tolerance and cost. Trial registration ClinicalTrials.gov under the no. NCT04742374 and date of registration 10 December 2020.

Allophanic soils are interesting in terms of environmental properties especially because of their potentialities as sinks for “greenhouse gases” by the way of C sequestration. These volcanic soils contain amorphous clays (allophanes) and exhibit higher organic carbon content than the one measured in other clay soils. We measured the C content of a set of allophanic soils and showed that the C content is positively correlated to the allophane content. We also measured the part of organic matter transformed into CO 2 during a respiration experiment and showed that the decomposition is lowered as the soils allophane content increases. Allophane aggregates are very close to the synthetic gels: high specific surface area large pore volume, fractal structure, large water content and important irreversible shrinkage during drying. In this work we characterized by Small Angle X-Ray Scattering (SAXS) the fractal structure of the allophane aggregates at the nano scale. We hypothesized that the peculiar structure and the associated low accessibility of the allophanic soils could explain the high organic carbon content and the associated poor transformation into CO 2 . The tortuous structure of the allophane aggregates plays the role of a labyrinth which fix and traps soil organic carbon.

Agroforestry is an increasingly popular farming system enabling agricultural diversification and providing several ecosystem services. In agroforestry systems, soil organic carbon (SOC) stocks are generally increased, but it is difficult to disentangle the different factors responsible for this storage. Organic carbon (OC) inputs to the soil may be larger, but SOC decomposition rates may be modified owing to microclimate, physical protection, or priming effect from roots, especially at depth. We used an 18-year-old silvoarable system associating hybrid walnut trees (Juglans regia × nigra) and durum wheat (Triticum turgidum L. subsp. durum) and an adjacent agricultural control plot to quantify all OC inputs to the soil – leaf litter, tree fine root senescence, crop residues, and tree row herbaceous vegetation – and measured SOC stocks down to 2 m of depth at varying distances from the trees. We then proposed a model that simulates SOC dynamics in agroforestry accounting for both the whole soil profile and the lateral spatial heterogeneity. The model was calibrated to the control plot only. Measured OC inputs to soil were increased by about 40 % (+ 1.11 t C ha−1 yr−1) down to 2 m of depth in the agroforestry plot compared to the control, resulting in an additional SOC stock of 6.3 t C ha−1 down to 1 m of depth. However, most of the SOC storage occurred in the first 30 cm of soil and in the tree rows. The model was strongly validated, properly describing the measured SOC stocks and distribution with depth in agroforestry tree rows and alleys. It showed that the increased inputs of fresh biomass to soil explained the observed additional SOC storage in the agroforestry plot. Moreover, only a priming effect variant of the model was able to capture the depth distribution of SOC stocks, suggesting the priming effect as a possible mechanism driving deep SOC dynamics. This result questions the potential of soils to store large amounts of carbon, especially at depth. Deep-rooted trees modify OC inputs to soil, a process that deserves further study given its potential effects on SOC dynamics.

Quantifying both soil organic carbon (SOC) and soil inorganic carbon (SIC) is essential to understand carbon (C) dynamics and to assess the atmospheric C sequestration potential in calcareous soils. The procedures usually used to quantify SOC and SIC involve pretreatments (decarbonation, carbonate removal) and calculations of the difference between C contents estimated by elemental analysis on raw and pretreated aliquots. These procedures lead to analytical bias associated with pretreatments, measurement deviations associated with sample heterogeneity, and cumulative errors associated with calculations. The Rock-Eval® analysis is a ramped thermal analysis that has been used in soil sciences since the 2000s, consisting of pyrolysis of the sample followed by oxidation of the residue. A single Rock-Eval® analysis on non-pretreated aliquots provides two parameters estimating the organic (TOC) and inorganic (MinC) C contents of the samples. Nevertheless, the Rock-Eval® protocol was standardised in the 1970s by IFP Energies Nouvelles for studying oil-bearing rocks and is thus not perfectly suited for soil study. Previous studies have suggested statistical corrections of the standard parameters to improve their estimations of C contents assessed by elemental analysis, but only a few of them have focused on the estimation of inorganic C content using the MinC parameter. Moreover, none of them have suggested adjustments to the standard Rock-Eval® protocol. This study proposes to adapt this protocol to optimise SOC and SIC quantifications in soil samples. Comparisons between SOC and SIC quantifications by elemental analysis and by Rock-Eval®, with and without statistical corrections of the standard TOC and MinC parameters, were carried out on 30 agricultural topsoils with a wide range of SOC and SIC contents. The results show that the standard Rock-Eval® protocol can properly estimate SOC contents once the TOC parameter is corrected. However, it cannot achieve a complete thermal breakdown of SIC amounts > 4 mg, leading to an underestimation of high SIC contents by the MinC parameter, even after correcting for this. Thus, the final oxidation isotherm is extended to 7 min to complete the thermal breakdown of SIC before the end of the analysis. This work is a methodological step to measure SOC and SIC contents in a single analytical run on a non-pretreated aliquot. More work is needed (i) on a wider range of soil samples with differing land use and other forms of carbonate mineral and sampling depths and (ii) to avoid the use of statistical corrections of the TOC and MinC parameters.

From 1991 to 1993, 90 children having received a kidney graft with a post-transplantation period of at least 12 months were included in a prospective study carried out in 18 French pediatric centers. After informed consent and randomization, children received recombinant human growth hormone (rhGH) (Genotonorm, Pharmacia peptide hormones) 30 U/m2 per week, either immediately on enrollment, for the treated group, or after 1 year of follow-up for the group serving as a control. After 1 year both groups were treated and we analyzed data during the subsequent years. Eighty-five children completed the 1-year study. Growth velocity was significantly increased by rhGH: 7.7 cm with a gain of +0.3 standard deviation score in the treated group versus 4.6 cm in the control group (P<0.0001) during the 1st year. Four factors predicted response to therapy: growth velocity prior to GH therapy, glomerular filtration rate (GFR) at the start, mode of corticosteroid administration, and degree of insulin resistance. After 1 year we observed a moderate, significant decrease in GFR in both groups. Biopsy-proven acute rejection episodes were not significantly more frequent during the 1st year in the group of patients who received rhGH: 9 in 44 versus 4 in 46 patients. The patients who rejected did not differ in terms of age, renal function at the start, and type of immunosuppression, but history of rejection before GH treatment was discriminatory: 6 of 17 children with two or more episodes had a new rejection versus 1 of 22 who had no or only one episode (P=0.01). Glucose tolerance was not modified after 1 year of GH therapy. During the subsequent years of treatment a decrease in growth velocity was noted: 5.9 cm at 2 years, 5.5 at 3 years, and 5.2 cm at 4 years. In conclusion, GH is efficient for improving growth velocity in short transplanted children, inducing clear-cut but limited catch-up growth. The risk of rejection was shown only in patients with a prior history of more than one rejection episode. [PUBLICATION ABSTRACT]

The quality of wind speed from different reanalyses (ERA5, COSMO-REA6 and CERRA) is assessed along the different coasts of mainland France. SYNOP (surface synoptic observations) wind measurements from Météo-France at 10 m height and floating LiDAR (Light Detection and Ranging) measurements from DGEC (Direction Générale de l'Énergie et du Climat) at 100 m height are used as reference. The inter-annual variability, distribution of wind, seasonal cycle, diurnal cycle and extremes are evaluated using several metrics (bias, correlation, normalized root mean square error). Results show that the shape of the 10 m wind seasonal cycle is well represented by all reanalyses. However, along the Mediterranean coast, wind speed is underestimated by ERA5, and overestimated by COSMO-REA6 during winter. COSMO-REA6 does not reproduce well the diurnal cycle along the Mediterranean coast, nor does ERA5 for the Atlantic coast. Overall, CERRA has better skills in representing surface wind speed on the three French seafronts, as well as for offshore wind speed at 100 m. The present study provides insights on the use of CERRA as a reference for offshore wind studies over the French maritime zone.

Fallowing is a common practice for the management of soil fertility in low-input cropping systems of the WestAfrican savanna, but has been threatened by the growing need for land in the sub-region for the past few decades. Proposals for alternatives to traditional fallowing must rely on a proper understanding of the soil biochemical dynamics occurring after fallow conversion to cropping. Two mesh-bag experiments were thus conducted in two sites (dry and sub-humid tropical climates) in Senegal to assess the role of site-related factors (climate, macrofaunal activity) and root-related factors (tree species, root diameter) on the decomposition of tree roots after clearing of fallow vegetation as measured from mass loss. Root decomposition was fastest – and even faster than predicted from a global model – in the wettest site (first order disappearance rate: 1.00 y-1 and 1.46–1.49 y-1 under dry and sub-humid conditions, respectively). Macrofauna accounted for half of root mass loss in the sub-humid site, with biomass removal occurring even during the dry season. Fastest disappearance for roots with ϕ < 5 mm occurred for Dichrostachys cinerea, and Combretum glutinosum. The influence of root chemical composition on decomposition patterns among tree species and root diameter classes was not clear, with effects of cell wall composition and nutrient content changing throughout the incubation period. Fast disappearance of dead roots suggests that cropping practices that allow conservation of live stumps, such as no-tillage and direct sowing, be promoted wherever possible to ensure soil conservation. It also suggests the possible management of tree species composition and, to a much lesser extent, of macrofauna during the fallow period to control root decomposition patterns and related nutrient transfers to crop biomass after fallow conversion.

Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP), a rare disorder affecting young adults, causes gradual weakness of the limbs, areflexia and impaired sensory function. New CIDP phenotypes without pathogenic antibodies but with modified cell profiles have been described. Treatments include corticotherapy, intravenous immunoglobulins, and plasmapheresis but the latter's action mechanisms remain unclear. Plasmapheresis supposedly removes toxic agents like antibodies from plasma but it is uncertain whether it has an immune-modulating effect. Also, the refining mechanisms of the two main plasmapheresis techniques--single plasma exchange and double filtration plasmapheresis (DFPP) - are different and unclear. This study aims to compare the evolution of peripheral lymphocyte profiles in patients with CIDP according to their treatment (single centrifugation plasmapheresis or DFPP) to better grasp the action mechanisms of both techniques. In this proof-of-concept, monocentric, prospective, Single-Case Experimental Design study, 5 patients are evaluated by alternating their treatment type (single plasma exchange or DFPP) for 6 courses of treatment after randomization to their first treatment type. Each course of treatment lasts 2-4 weeks. For single plasma exchange, 60 ml/kg plasma will be removed from the patient and replaced with albumin solutes, with a centrifugation method to avoid the immunological reaction caused by the membrane used with the filtration method. For DFPP, 60 ml/kg plasma will be removed from the patient with a plasma separator membrane, then processed via a fractionator membrane to remove molecules of a greater size than albumin before returning it to the patient. This technique requires no substitution solutes, only 20 g of albumin to replace what would normally be lost during a session. The primary outcome is the difference between the two plasmapheresis techniques in the variation of the TH1/TH17 ratio over the period D0H0-D0H3 and D0H0-D7. Secondary outcomes include the variation in lymphocyte subpopulations at each session and between therapeutic plasmapheresis techniques, the clinical evolution, tolerance and cost of treatments. Understanding the action mechanisms of single plasma exchange and DFPP will help us to offer the right treatment to each patient with CIPD according to efficacy, tolerance and cost.

The link between travel and the risk of venous thromboembolic disease (VTED) has been widely suspected. However, only cases or series of cases have been reported in the literature. By means of a case-control study, we sought to confirm this relationship and to determine the main features, if any, of these posttravel VTEDs. The history, in particular the history of recent travel, of 160 patients presenting in our department with VTED was scrupulously investigated. All journeys undertaken during the preceding 4 weeks and lasting > 4 h by whatever means of transport were considered. The same questionnaire was submitted to a control group. When the two groups of patients are compared, a history of recent travel is found almost four times more frequently in the VTED group (p < 0.0001). The odds ratio for having a VTED in patients who traveled was 3.98 (95% confidence interval, 1.9 to 8.4). Means of travel used included the train in 2 cases, airplane in 9, and car in 28. Mean duration of travel was 5.4+/-2.1 h. These posttravel VTEDs are not confined to a specific location, seem to involve no particular predisposition, and are more often \"idiopathic.\" This fact supports the hypothesis that travel alone can produce vein clot formation. A history of recent travel is a risk factor for VTED. Posttravel venous thrombotic events can occur after short journeys in patients with no other risk factors or concomitant disease

Some general notions on soil organic carbon (SOC) sequestration and the difficulties to evaluate this process globally are presented. Problems of time- and space- scales are emphasized. SOC erosion, which is generally difficult to evaluate in relation to land use changes, is discussed in detail. Different aspects of SOC sequestration on the Lesser Antilles are presented for a wide range of soil types. Comparisons between soils revealed that the SOC stocks in the Lesser Antilles are highly dependent upon the mineralogy: higher stocks for allophanic (ALL) soils than for low activity clay (LAC) and high activity clay (HAC) soils. But in terms of potential of SOC sequestration (pSeq-SOC, differences between permanent vegetation and continuous cultivation situations), there are no differences between ALL and LAC soils (22.9 and 23.3 tC. ha−1, respectively). On the other hand, the potentials of SOC sequestration were higher for HAC soils (30.8 – 59.4 tC. ha−1, with the higher levels in the less Mg- and Na-affected Vertisol). Sheet erosion is a serious problem for Vertisol with high Mg and Na on exchange complex, causing high dispersability of fine elements. Thus, the lower SOC levels in these soils may be partly due to erosion losses. Laboratory incubations have shown that 37 – 53% of the protected SOC in these soils was located in aggregates larger than 0.2 mm. The effect of agricultural practices on SOC sequestration was studied for the Vertisols. Intensification of pastures led to higher plant productivity and higher organic matter restitutions and SOC sequestration. The gain was 53.5 and 25.4 tC. ha−1 for the low and high-Mg Vertisol, respectively (0–20 cm layer). SOC sequestration with pastures also depends upon the plot history with lower mean annual increase in SOC for the initially eroded (1.0 gC . kg−1 soil . yr−1) than for the non-degraded (1.5 gC . kg−1 soil . yr−1) Vertisol. Loss of SOC in a pasture-market gardening rotation was 22.2 tC . ha−1 with deep (30–40 cm) and 10.7 tC . ha−1 with surface (10–15 cm) tillage. It was unclear whether the differences in SOC losses were due to mineralization and/or to erosion.