The coronavirus disease 2019 (COVID-19) pandemic is a global health care emergency. Although reverse-transcription polymerase chain reaction testing is the reference standard method to identify ...patients with COVID-19 infection, chest radiography and CT play a vital role in the detection and management of these patients. Prediction models for COVID-19 imaging are rapidly being developed to support medical decision making. However, inadequate availability of a diverse annotated data set has limited the performance and generalizability of existing models. To address this unmet need, the RSNA and Society of Thoracic Radiology collaborated to develop the RSNA International COVID-19 Open Radiology Database (RICORD). This database is the first multi-institutional, multinational, expert-annotated COVID-19 imaging data set. It is made freely available to the machine learning community as a research and educational resource for COVID-19 chest imaging. Pixel-level volumetric segmentation with clinical annotations was performed by thoracic radiology subspecialists for all COVID-19-positive thoracic CT scans. The labeling schema was coordinated with other international consensus panels and COVID-19 data annotation efforts, the European Society of Medical Imaging Informatics, the American College of Radiology, and the American Association of Physicists in Medicine. Study-level COVID-19 classification labels for chest radiographs were annotated by three radiologists, with majority vote adjudication by board-certified radiologists. RICORD consists of 240 thoracic CT scans and 1000 chest radiographs contributed from four international sites. It is anticipated that RICORD will ideally lead to prediction models that can demonstrate sustained performance across populations and health care systems.
Premise
While angiosperms respond uniformly to abscisic acid (ABA) by stomatal closure, the response of ferns to ABA is ambiguous. We evaluated the effect of endogenous ABA, hydrogen peroxide (H2O2), ...nitric oxide (NO), and Ca2+, low and high light intensities, and blue light (BL) on stomatal opening of Pleopeltis polypodioides.
Methods
Endogenous ABA was quantified using gas chromatography‐mass spectrometry; microscopy results and stomatal responses to light and chemical treatments were analyzed with Image J.
Results
The ABA content increases during initial dehydration, peaks at 15 h and then decreases to one fourth of the ABA content of hydrated fronds. Following rehydration, ABA content increases within 24 h to the level of hydrated tissue. The stomatal aperture opens under BL and remains open even in the presence of ABA. Closure was strongly affected by BL, NO, and Ca2+, regardless of ABA, H2O2 effect was weak.
Conclusions
The decrease in the ABA content during extended dehydration and insensitivity of the stomata to ABA suggests that the drought tolerance mechanism of Pleopeltis polypodioides is independent of ABA.
Although heat and desiccation stresses often coincide, the response to heat especially in desiccation tolerant plants is rarely studied. We subjected hydrated
fronds to temperatures up to 50°C and ...dehydrated fronds up to 65°C for 24 h. The effect of heat stress was evaluated using morphological changes, photosystem (PS) II efficiency, and metabolic indicators. Pinnae of dried fronds exposed to more than 40°C curled tighter and became brittle compared to fronds dried at lower temperatures. Exposure to > 50°C leads to discolored fronds after rehydration. Hydrated fronds turned partially brown at > 35°C. Chlorophyll fluorescence (F
) and quantum yield (Q
) increased following re-hydration but the recovery process after 40°C treatment lasted longer than at lower temperatures. Similarly, hydrated fronds showed reduced Q
when exposed to > 40°C. Dried and hydrated fronds remained metabolically active up to 40°C. Hydroperoxides and lipid hydroperoxides in dried samples remained high up to 50°C, but decreased in hydrated fronds at > 40°C. Catalase (CAT) and glutathione (GSH) oxidizing activities remained high up to 40°C in dehydrated fronds and up to 35°C in hydrated fronds. Major fatty acids detected in both dehydrated and hydrated fronds included palmitic (C16:0) and stearic (C18:0) acids, oleic (18:1), linoleic (C18:2); and linolenic (C18:3) acids. Linolenic acid was most abundant. In dried fronds, all fatty acids decreased at > 35°C. The combined data indicate that the thermotolerance of dry fronds is about 55°C but is at least 10°C lower for hydrated fronds.
During its three terms in office, the National-led government (2008-2017) introduced a number of family income support policies which served to further embed the radical paradigm shift that had ...occurred under the National governments when in power from 1990 to 1999. This earlier comprehensive retrenchment programme by National transformed the welfare state from one based on the notion that the state would provide for people in need, to a residual welfare state in which people were supposed to seek support from the state only as a last resort. Family income policy was targeted to a narrower group of recipients, the conditions for benefit eligibility were tightened, benefit payments reduced and a discourse of welfare dependency that stigmatised benefit recipients was promoted. From 2008, this article argues National's measures were merely incremental adjustments to its previous policy direction and which served to further embed the paradigm shift it had introduced in the 1990s. The Labour-led government elected in 2017, despite suggesting it would make radical changes, has made little significant effort to reverse this policy direction. It would appear that National's social policy legacy from the 1990s has become so well-entrenched, that it is difficult for the Labour Party to challenge the targeted, stigmatising approach that characterises family incomes policy.
We studied the effect of peltate scales on water uptake and loss of the desiccation-tolerant epiphytic fern Pleopeltis polypodioides using optical and FTIR microscopy and staining with calcofluor, ...solophenyl flavine7GFE, and Ruthenium Red. We provide information on structure, property, and function of the scales by measuring water uptake and dehydration, contact angles, and metabolic activity. Peltate scales mainly contain cellulose, xylogalactans, and pectin. Water is absorbed from the center of scales, and the overlapping arrangement of scales facilitates surface spreading of water. Intact fronds hydrated fully within 5 h of imbibition of the apical pinna, without scales water uptake stopped after 1 h. Hydration rates via rhizomes followed a longer time course but also improved in the presence of scales. Fronds with and without scales lost half of their water content in 15 or 4 h, respectively. The overall metabolism of rapidly dehydrated fronds was significantly reduced compared with slowly dehydrated fronds. Thus, water management and metabolism of Pleopeltis are dependent on surface properties determined by peltate scales.
Alterations in cellular metabolism underpin macrophage activation, yet little is known regarding how key immunological molecules regulate metabolic programs in macrophages. Here we uncover a function ...for the antigen presenting molecule CD1d in the control of lipid metabolism. We show that CD1d-deficient macrophages exhibit a metabolic reprogramming, with a downregulation of lipid metabolic pathways and an increase in exogenous lipid import. This metabolic rewiring primes macrophages for enhanced responses to innate signals, as CD1d-KO cells show higher signalling and cytokine secretion upon Toll-like receptor stimulation. Mechanistically, CD1d modulates lipid import by controlling the internalization of the lipid transporter CD36, while blocking lipid uptake through CD36 restores metabolic and immune responses in macrophages. Thus, our data reveal CD1d as a key regulator of an inflammatory-metabolic circuit in macrophages, independent of its function in the control of T cell responses.
CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs) are potent suppressors of the adaptive immune system, but their effects on innate immune cells are less well known. Here we demonstrate a previously ...uncharacterized function of Tregs, namely their ability to steer monocyte differentiation toward alternatively activated macrophages (AAM). AAM are cells with strong antiinflammatory potential involved in immune regulation, tissue remodeling, parasite killing, and tumor promotion. We show that, after coculture with Tregs, monocytes/macrophages display typical features of AAM, including up-regulated expression of CD206 (macrophage mannose receptor) and CD163 (hemoglobin scavenger receptor), an increased production of CCL18, and an enhanced phagocytic capacity. In addition, the monocytes/macrophages have reduced expression of HLA-DR and a strongly reduced capacity to respond to LPS in terms of proinflammatory mediator production (IL-1β, IL-6, IL-8, MIP-1α, TNF-α), NFκB activation, and tyrosine phosphorylation. Mechanistic studies reveal that CD4⁺CD25⁺CD127lowFoxp3⁺ Tregs produce IL-10, IL-4, and IL-13 and that these cytokines are the critical factors involved in the suppression of the proinflammatory cytokine response. In contrast, the Treg-mediated induction of CD206 is entirely cytokine-independent, whereas the up-regulation of CD163, CCL18, and phagocytosis are (partly) dependent on IL-10 but not on IL-4/IL-13. Together these data demonstrate a previously unrecognized function of CD4⁺CD25⁺Foxp3⁺ Tregs, namely their ability to induce alternative activation of monocytes/macrophages. Moreover, the data suggest that the Treg-mediated induction of AAM partly involves a novel, cytokine-independent pathway.
This lecture commemorates the life of one of our most distinguished judges and citizens, Sir Owen Woodhouse. His compassion, generosity of spirit and social conscience were reflected in his work as ...President of the Court of Appeal, President of the Law Commission and Chairman of the Royal Commission on Compensation for Injury that recommended a no-fault accident compensation scheme and laid the foundations for the Accident Compensation Corporation (ACC) scheme. He made an immense contribution to New Zealand's law and society.
The epiphytic fern Pleopeltis polypodioides can tolerate repeated drying and rehydration events without conspicuous damage. To understand the biochemical principles of drought-tolerance, we analyzed ...the effect of dehydration and rehydration at 25 °C on hydroperoxide and lipid hydroperoxide, the activities of antioxidative (catalase and glutathione-oxidizing) enzymes and evaluated changes in fatty acid composition and saturation levels. Dehydration increased peroxide concentration and the activity of glutathione oxidases, but reduced catalase activity. During dehydration, the biosynthesis of palmitic (C16:0), linoleic (C18:2), linolenic (C18:3) and stearic acid (C18:0) increased 18, 12, 20, and 8-fold, respectively. In contrast, rehydration lowered levels of peroxides, the activity of glutathione-oxidizing enzymes, and fatty acids but increased catalase activity. The coordinated changes during de- and rehydration suggest that lipids and oxidative and antioxidative enzymes are components of the drought-resistance system.
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