8 research outputs found
Gene Expression Profile and Acute Gene Expression Response to Sclerostin Inhibition in Osteogenesis Imperfecta Bone
Sclerostin antibody (SclAb) therapy has been suggested as a novel therapeutic approach toward addressing the fragility phenotypic of osteogenesis imperfecta (OI). Observations of cellular and transcriptional responses to SclAb in OI have been limited to mouse models of the disorder, leaving a paucity of data on the human OI osteoblastic cellular response to the treatment. Here, we explore factors associated with response to SclAb therapy in vitro and in a novel xenograft model using OI bone tissue derived from pediatric patients. Bone isolates (approximately 2âmm3) from OI patients (OI type III, type III/IV, and type IV, n =â7; nonâOI control, n =â5) were collected to media, randomly assigned to an untreated (UN), lowâdose SclAb (TRL, 2.5âÎŒg/mL), or highâdose SclAb (TRH, 25âÎŒg/mL) group, and maintained in vitro at 37°C. Treatment occurred on days 2 and 4 and was removed on day 5 for TaqMan qPCR analysis of genes related to the Wnt pathway. A subset of bone was implanted s.c. into an athymic mouse, representing our xenograft model, and treated (25âmg/kgâs.c. 2Ă/week for 2/4âweeks). Implanted OI bone was evaluated using ÎŒCT and histomorphometry. Expression of Wnt/Wntârelated targets varied among untreated OI bone isolates. When treated with SclAb, OI bone showed an upregulation in osteoblast and osteoblast progenitor markers, which was heterogeneous across tissue. Interestingly, the greatest magnitude of response generally corresponded to samples with low untreated expression of progenitor markers. Conversely, samples with high untreated expression of these markers showed a lower response to treatment. in vivo implanted OI bone showed a boneâforming response to SclAb via ÎŒCT, which was corroborated by histomorphometry. SclAb induced downstream Wnt targets WISP1 and TWIST1, and elicited a compensatory response in Wnt inhibitors SOST and DKK1 in OI bone with the greatest magnitude from OI cortical bone. Understanding patientsâ genetic, cellular, and morphological bone phenotypes may play an important role in predicting treatment response. This information may aid in clinical decisionâmaking for pharmacological interventions designed to address fragility in OI. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156449/2/jbm410377_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156449/1/jbm410377.pd
Control of electronic properties by lanthanide size and manganese oxidation state in the MnIII/MnIV RuddlesdenâPopper phases Ln2?xSr1+xMn2O7
The magnetic behaviour of then=2 RuddlesdenâPopper phases Sr2 LnMn2 O7 is very sensitive to the Ln3+ lanthanide cation. In samples with larger, more basic lanthanide cations (Ln=Nd, Pr) antiferromagnetic phases with ordering temperatures in the region of 130 K co-exist with phases showing a magnetic response suggestive of superparamagnetism or the development of small ferromagnetic clusters at high temperature. The magnetic transition temperature drops to 20 K in samples containing smaller, acidic cations (Ln=GdâEr, Y). In the latter group of compounds, the transition is from a CurieâWeiss paramagnet to a spin-glass; there is no evidence for long-range magnetic order. This change in behaviour can be explained by considering the variation in the relative strength of superexchange and double exchange interactions as a function of the lanthanide cation. The influence of manganese oxidation state on magnetic response is investigated in the Sr2-x Ln1+x Mn2 O7 composition range (0.0?x?0.7) for Ln=Nd, Tb
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Reimagining Childrenâs Rights in the US
ImportanceThe US faces a pivotal moment of opportunity and risk regarding issues affecting children (aged 0-17 years). Although the US remains the only United Nations member state to not have ratified the Convention on the Rights of the Child (CRC), a child rights framework is essential for child health professionals seeking to advance many issues affecting children in the US. The Reimagining Children's Rights project (2020-2021) conducted an in-depth environmental scan of relevant literature and policy analysis using the Three Horizons design process to assess strategies that could advance the rights and well-being of children in the US. The project was overseen by a steering committee and informed by an advisory committee composed of youth leaders and experts in children's rights, advocacy, health, law, and a range of child-specific issues (eg, youth justice, early childhood development), who provided expert input on strategic considerations for advancing children's rights.ObservationsSeven findings about advancing children's rights in the US are notable, all reflecting current gaps and opportunities for using a whole-child rights framework in the US, even without formal adoption of the CRC. Actionable strategies, tactics, and tools to leverage sustainable change in the multitude of issue areas can advance the current state of children's rights. High-potential strategies for catalyzing advancement of children's rights include youth activism, innovations in governance and accountability, legislative action, impact litigation, place-based initiatives, education and public awareness, alignment with other children's movements, and research. The child rights framework is unifying and adaptive to future unforeseen challenges.Conclusions and relevanceChildren's rights provide a powerful, synergistic framework for child health professionals-in partnership with youth and other leaders-to increase equity and protect the rights and well-being of all children in the US
Whole-genome sequencing reveals host factors underlying critical COVID-19
Altres ajuts: Department of Health and Social Care (DHSC); Illumina; LifeArc; Medical Research Council (MRC); UKRI; Sepsis Research (the Fiona Elizabeth Agnew Trust); the Intensive Care Society, Wellcome Trust Senior Research Fellowship (223164/Z/21/Z); BBSRC Institute Program Support Grant to the Roslin Institute (BBS/E/D/20002172, BBS/E/D/10002070, BBS/E/D/30002275); UKRI grants (MC_PC_20004, MC_PC_19025, MC_PC_1905, MRNO2995X/1); UK Research and Innovation (MC_PC_20029); the Wellcome PhD training fellowship for clinicians (204979/Z/16/Z); the Edinburgh Clinical Academic Track (ECAT) programme; the National Institute for Health Research, the Wellcome Trust; the MRC; Cancer Research UK; the DHSC; NHS England; the Smilow family; the National Center for Advancing Translational Sciences of the National Institutes of Health (CTSA award number UL1TR001878); the Perelman School of Medicine at the University of Pennsylvania; National Institute on Aging (NIA U01AG009740); the National Institute on Aging (RC2 AG036495, RC4 AG039029); the Common Fund of the Office of the Director of the National Institutes of Health; NCI; NHGRI; NHLBI; NIDA; NIMH; NINDS.Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care or hospitalization after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes-including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)-in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease