The aim of this in vitro study was to evaluate if osteoclasts (OCs) and dendritic cells (DCs), both of monocyte origin, can support the survival of normal human plasma cells (PCs). PCs differentiate ...from plasmablasts (PBs) arising from activated B cells, essentially memory B cells. To study the survival of both PBs (CD20lowCD38highCD138neg) and PCs (CD20negCD38brightCD138bright), we generated pre-PBs (CD20lowCD38posCD138neg) from CD40-activated B cells (CD20highCD38negCD138neg) and cultured them on DCs or OCs in the presence of added IL-6. By quantitative and qualitative study, we showed that DCs support the survival of PBs and early PCs, but not that of PCs. In contrast, OCs support the survival of PBs, early PCs and PCs. PCs surviving on OCs 12 days after pre-PB input display phenotypic features of bone marrow PCs, CD138brightCD38brightHLA-DRlowCD45dim. The ability for OCs to support the survival of PCs was fully dependent on cell–cell contact and not inhibited by BCMA-Fc suggesting that secreted BAFF and APRIL were not involved.
In aqueous solution, the biocidal double-tailed cationic surfactant, di-
n-decyl-dimethyl-ammonium chloride can form inclusion complexes with various cyclodextrins (α-
CD, β-
CD, γ-
CD,
HP-α-
CD,
...HP-β-
CD and
CM-β-
CD). A physicochemical study has been performed to investigate the association parameters of these host–guest complexes by combining the use of ammonium and chloride selective electrodes, NMR spectroscopy and molecular modeling. stoichiometries, equilibrium constants and geometries were determined by resorting to a specific algorithm. The antimicrobial activity of the encapsulated ammonium surfactant was compared with that of the free ammonium showing three different behaviors depending on the cyclodextrin. The close relationship between the complex structure and the biocidal activity is used to propose a delivery molecular mechanism.
Lung transplantation (LTx) is a steadily expanding field. The considerable developments have been driven over the years by indefatigable work conducted at LTx centers to improve donor and recipient ...selection, combined with multifaceted efforts to overcome challenges raised by the surgical procedure, perioperative care, and long-term medical complications. One consequence has been a pruning away of contraindications over time, which has, in some ways, complicated the patient selection process.
The Francophone Pulmonology Society (Société de Pneumology de Langue Française, SPLF) set up a task force to produce up-to-date working guidelines designed to assist pulmonologists in managing end-stage respiratory insufficiency, determining which patients may be eligible for LTx, and appropriately timing LTx-center referral. The task force examined the most recent literature and evaluated the risk factors that limit patient survival after LTx. Ideally, the objectives of LTx are to prolong life while also improving quality of life. The guidelines developed by the task force apply to a limited resource and are consistent with the ethical principles described below.
SARS-CoV-2 positive pregnant women are at higher risk of adverse outcomes, but little evidence is available on how variants impact that risk. We aim to evaluate maternal and perinatal outcomes among ...unvaccinated pregnant women that tested positive for SARS-CoV-2, stratified by pre-Delta, Delta, and Omicron periods.
This prospective study enrolled women from March 2020 to September 2022. Exposure to the different SARS-CoV-2 variants was defined by their periods of predominance. The primary outcome was severe maternal adverse outcome defined as either intensive care unit admission, acute respiratory distress syndrome, advanced oxygen supplementation, or maternal death. The secondary outcomes were preterm birth and other perinatal outcomes.
Overall, 1402, 262, and 391 SARS-CoV-2 positive pregnant women were enrolled during the pre-Delta, Delta, and Omicron periods respectively. Severe maternal adverse outcome was reported in 3.4% (n = 947/1402; 95% confidence intervals (95%CI) 2.5–4.5), 6.5% (n = 7/262; 95%CI 3.8–10.2), and 1.0% (n = 4/391; 95%CI 0.3–2.6) of women during the pre-Delta, Delta, and Omicron periods. The risk of severe maternal adverse outcome was higher during the Delta vs pre-Delta period (adjusted risk ratio (aRR) = 1.8; 95%CI 1.1–3.2) and lower during the Omicron vs pre-Delta period (aRR = 0.3; 95%CI, 0.1–0.8). The risks of hospitalization for COVID-19 were 12.6% (n = 176/1402; 95%CI 10.9–14.4), 17.2% (n = 45/262; 95%CI 12.8–22.3), and 12.5% (n = 49/391; 95%CI 9.4–16.2), during the pre-Delta, Delta, and Omicron period, respectively. Pregnancy complications occurred after SARS-CoV-2 exposure in 30.0% (n = 363/1212; 95%CI 27.4–32.6), 35.2% (n = 83/236; 95%CI 29.1–41.6), and 30.3% (n = 105/347; 95%CI 25.5–35.4) of patients during the pre-Delta, Delta, and Omicron periods, respectively. Stillbirths were reported in 0.5% (n = 6/1159; 95%CI 0.2–1.1), 2.8% (n = 6/210; 95%CI 1.0–6.0), and 0.9% (n = 2/213; 95%CI 0.1–3.4) or patients during the pre-Delta, Delta, and Omicron periods respectively.
The Delta period was associated with a higher risk of severe maternal adverse outcome and the Omicron period with a lower risk of severe adverse outcome compared to pre-Delta era. The reported risk of hospitalization was high during the Omicron period and should not be trivialized.
Swiss Federal Office of Public Health, Fondation CHUV.
Global dust storms on Mars are rare but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere, primarily owing to solar ...heating of the dust. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars. Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes, as well as a decrease in the water column at low latitudes. Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H2O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H2O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals. The observed changes in H2O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere.
The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today. A number of different measurements of methane show evidence of ...transient, locally elevated methane concentrations and seasonal variations in background methane concentrations. These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere, which—given methane’s lifetime of several centuries—predicts an even, well mixed distribution of methane. Here we report highly sensitive measurements of the atmosphere of Mars in an attempt to detect methane, using the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter from April to August 2018. We did not detect any methane over a range of latitudes in both hemispheres, obtaining an upper limit for methane of about 0.05 parts per billion by volume, which is 10 to 100 times lower than previously reported positive detections. We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally.
Extensive grazing applied in the form of low instantaneous pressure over a long period is a widespread management practice in protected areas. However this kind of stocking method does not always ...achieve the expected results, in particular because it fails to limit colonization by woody plants.This is the case in the relict xero-halophytic grasslands of the northern Mediterranean coastal region, subjected to widespread colonization by the shrub
Phillyrea angustifolia
despite the presence of extensive grazing. In this study, we investigated, for an equal annual stocking rate, the respective impact of high stocking density applied over a short period (mob grazing) and low stocking density applied over a long period on both
P. angustifolia
and herbaceous cover, using an in situ experimental design run for 7 years. Only mob grazing was effective both in controlling the establishment and increasing the mortality of
P. angustifolia
individuals. We did not find any difference after the 7 years of experimentation between the two stocking methods with regard to the herbaceous community parameters tested: species richness, diversity, evenness, contribution of annual characteristic species. By contrast, the exclusion of domestic grazing led to a strong reduction of these values.The use of mob grazing may be well suited for meeting conservation goals such as maintaining open habitats in these grasslands.
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