41 research outputs found
Recognizing pedogenic features in Paleogene sandstones and silcretes in Belgium: a key-feature for paleoenvironmental and sourcing material studies
International audienceA few sandstones occurring in Belgium, especially those from Paleogene strata, share many common features with pedogenic and groundwater silcretes documented in the Paris Basin in France, in South Africa and in Australia (e.g. Thiry, 1999; Summerfield, 1983; Webb & Golding, 1998,). Here we present a review of the criteria that may be used to assess the pedogenic (or "groundwater") origin for sandstones and silcretes. At field scale, pedogenic features in silcrete often consist in the development of vertical (columnar) or nodular structures and/or layers (horizons) due to vetical percolation (illuviation) and transformation of materials in the profile porosity and cracks. Groundwater silcrete often exhibit a typical mammilated surface (e.g. Nash & Ullyot, 2007). Root and rootlet casts, sometimes with silicified root or wood material, also indicate that the rock evolved at the surface or near-surface. At microscopic scale, illuviation of silt and clays in the vadose or water-table environment results in the formation of a series of finely-laminated coatings and infillings. These pedofeatures consist in "typic", "crescent", "capping", "pendent", "micropan" and "crust" coatings (Bullock et al., 1985). Irregular rounded structures or "glaebules" also develop as well as micro-columnar or prismatic textures. Many of them have been observed in pedogenic silcretes around the world (e.g. Thiry, 1999) but also in Paleogene silcrete in Belgium (e.g. Veldman et al., in review). Of particular importance is the concentration of fine-grained titanium-oxides in pedogenic silcrete. These Ti-oxides most probably originated from the weathering of clay material and were concentrated via the same pedogenic processes which concentrated silica in the silcrete profile (Thiry, 1997). In sandstones with a pure sand matrix, where no or few fine-grained material is available for illuviation, assessing the pedogenic origin for the silicification is much more difficult based solely on microtextural observations. New perspectives may arise from trace-element analysis in the quartz cement overgrowing the grains. For example, combining cathodoluminescence imaging (CL) and electron microprobe analysis (EPMA) allowed the detec on of abnormally-high concentration of Al and K in the quartz cement relative to the quartz grains in the Grandglise Thanetian sandstone in the Mons Basin (figure). This suggests that first the weathering of glauconite, which is actually observed here, is the likely source for silica and secondly, the evidence for aluminum migration would indicate strongly acidic conditions in the pore fluids
Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.
There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions
Single cell transcriptome analysis reveals disease-defining T cell subsets in the tumor microenvironment of classic Hodgkin lymphoma
Hodgkin lymphoma is characterized by an extensively dominant tumor microenvironment (TME) composed of different types of noncancerous immune cells with rare malignant cells. Characterization of the cellular components and their spatial relationship is crucial to understanding cross-talk and therapeutic targeting in the TME. We performed single-cell RNA sequencing of more than 127,000 cells from 22 Hodgkin lymphoma tissue specimens and 5 reactive lymph nodes, profiling for the first time the phenotype of the Hodgkin lymphoma–specific immune microenvironment at single-cell resolution. Single-cell expression profiling identified a novel Hodgkin lymphoma–associated subset of T cells with prominent expression of the inhibitory receptor LAG3, and functional analyses established this LAG3+ T-cell population as a mediator of immunosuppression. Multiplexed spatial assessment of immune cells in the microenvironment also revealed increased LAG3+ T cells in the direct vicinity of MHC class II–deficient tumor cells. Our findings provide novel insights into TME biology and suggest new approaches to immune-checkpoint targeting in Hodgkin lymphoma. SIGNIFICANCE: We provide detailed functional and spatial characteristics of immune cells in classic Hodgkin lymphoma at single-cell resolution. Specifically, we identified a regulatory T-cell–like immunosuppressive subset of LAG3+ T cells contributing to the immune-escape phenotype. Our insights aid in the development of novel biomarkers and combination treatment strategies targeting immune checkpoints
A Narrative Review of Motor Competence in Children and Adolescents: What We Know and What We Need to Find Out
Lack of physical activity is a global public health problem causing not only morbidity and premature mortality, but it is also a major economic burden worldwide. One of the cornerstones of a physically active lifestyle is Motor Competence (MC). MC is a complex biocultural attribute and therefore, its study requires a multi-sectoral, multi-, inter- and transdisciplinary approach. MC is a growing area of research, especially in children and adolescents due to its positive association with a plethora of health and developmental outcomes. Many questions, however, remain to be answered in this field of research, with regard to: (i) Health and Developmental-related Associations of MC; (ii) Assessment of MC; (iii) Prevalence and Trends of MC; (iv) Correlates and Determinants of MC; (v) MC Interventions, and (vi) Translating MC Research into Practice and Policy. This paper presents a narrative review of the literature, summarizing current knowledge, identifying key research gaps and presenting questions for future investigation on MC in children and adolescents. This is a collaborative effort from the International Motor Competence Network (IMCNetwork) a network of academics and researchers aiming to promote international collaborative research and knowledge translation in the expansive field of MC. The knowledge and deliverables generated by addressing and answering the aforementioned research questions on MC presented in this review have the potential to shape the ways in which researchers and practitioners promote MC and physical activity in children and adolescents across the worl
Comparison of selenophene and thienothiophene incorporation into pentacyclic lactam-based conjugated polymers for organic solar cells
A global genomic analysis of Salmonella Concord reveals lineages with high antimicrobial resistance in Ethiopia.
Antimicrobial resistant Salmonella enterica serovar Concord (S. Concord) is known to cause severe gastrointestinal and bloodstream infections in patients from Ethiopia and Ethiopian adoptees, and occasional records exist of S. Concord linked to other countries. The evolution and geographical distribution of S. Concord remained unclear. Here, we provide a genomic overview of the population structure and antimicrobial resistance (AMR) of S. Concord by analysing genomes from 284 historical and contemporary isolates obtained between 1944 and 2022 across the globe. We demonstrate that S. Concord is a polyphyletic serovar distributed among three Salmonella super-lineages. Super-lineage A is composed of eight S. Concord lineages, of which four are associated with multiple countries and low levels of AMR. Other lineages are restricted to Ethiopia and horizontally acquired resistance to most antimicrobials used for treating invasive Salmonella infections in low- and middle-income countries. By reconstructing complete genomes for 10 representative strains, we demonstrate the presence of AMR markers integrated in structurally diverse IncHI2 and IncA/C2 plasmids, and/or the chromosome. Molecular surveillance of pathogens such as S. Concord supports the understanding of AMR and the multi-sector response to the global AMR threat. This study provides a comprehensive baseline data set essential for future molecular surveillance
T cell control in autoimmune bullous skin disorders
Autoimmune bullous disorders are a group of severe skin diseases characterized clinically by blisters and erosions of skin and/or mucous membranes. A hallmark of these disorders is the presence of IgG and occasionally IgA autoantibodies that target distinct adhesion structures of the epidermis, dermoepidermal basement membrane, and anchoring fibrils of the dermis. This Review focuses on the potential role of autoreactive T cells in the pathogenesis of these disorders. Pemphigus vulgaris (PV) and bullous pemphigoid (BP) are the best-characterized bullous disorders with regard to pathogenesis and T cell involvement. Activation of autoreactive T cells in PV and BP is restricted by distinct HLA class II alleles that are prevalent in individuals with these disorders. Autoreactive T cells are not only present in patients but can also be detected in healthy individuals. Recently, a subset of autoreactive T cells with remarkable regulatory function was identified in healthy individuals and to a much lesser extent in patients with PV, suggesting that the occurrence of autoimmune bullous disorders may be linked to a dysfunction of Tregs
The Use of Off-Label Medications in Newborn Infants Despite an Approved Alternative Being Available—Results of a National Survey
Neonates continue to be treated with off-label or unlicensed drugs while in hospital. However, some medications that have previously been used in adults underwent clinical testing and licensure for use with a different indication in the neonatal and pediatric population. Almost always, the marketing of these newly approved substances in a niche indication is accompanied by a steep increase in the price of the compound. We investigated the use of the approved formulation or the cheaper off-label alternative of Ibuprofen (Pedea®), Propanolol (Hemangiol®) and Caffeine Citrate (Peyona®) in neonatal clinical practice by conducting a National Survey of 214 Perinatal Centers in Germany. We also assessed price differences between on- and off-label alternatives and the extend of the clinical development program of the on-label medication in the neonatal population. On-label medication was more frequently used than the off-label alternative in all indications (PDA: on-label to off-label ratio 1:0.26, Apnea: 1:0.56, Hemangioma 1:0.76). All sponsors did conduct placebo-controlled Phase III trials with efficacy and safety endpoints in the target population and the number of participants in the target population varied between 82 and 497. Costs for the three drugs in their approved and marketed formulations increased in median 405-fold compared with the corresponding off-label alternative. Overall, about one out of three neonatologists prescribed an off-label or non-approved drug to patients despite an alternative medication that is approved for the indication in the target population being available
Cultivating Europe: Democratic Europe - Social Europe - Educated Europe
Cultivating Europe: Democratic Europe - Social Europe - Educated Europ