Search results

Tortajada, Agustín et alt. ; C3 glomerulopathies (C3G) are a group of severe renal diseases with distinct patterns of glomerular inflammation and C3 deposition caused by complement dysregulation. Here we report the identification of a familial C3G-associated genomic mutation in the gene complement factor H-related 1 (CFHR1), which encodes FHR1. The mutation resulted in the duplication of the N-terminal short consensus repeats (SCRs) that are conserved in FHR2 and FHR5. We determined that native FHR1, FHR2, and FHR5 circulate in plasma as homo- and hetero-oligomeric complexes, the formation of which is likely mediated by the conserved N-terminal domain. In mutant FHR1, duplication of the N-terminal domain resulted in the formation of unusually large multimeric FHR complexes that exhibited increased avidity for the FHR1 ligands C3b, iC3b, and C3dg and enhanced competition with complement factor H (FH) in surface plasmon resonance (SPR) studies and hemolytic assays. These data revealed that FHR1, FHR2, and FHR5 organize a combinatorial repertoire of oligomeric complexes and demonstrated that changes in FHR oligomerization influence the regulation of complement activation. In summary, our identification and characterization of a unique CFHR1 mutation provides insights into the biology of the FHRs and contributes to our understanding of the pathogenic mechanisms underlying C3G. Copyright © 2013, American Society for Clinical Investigation. ; Work in this report was funded by the Spanish Ministerio de Economía y Competitividad (SAF2011-26583), the Fundación Renal Iñigo Alvarez de Toledo and the 7FP European Union project EURenOmics to S. Rodríguez de Córdoba; the "Ramón Areces" Foundation, the Spanish Ministerio de Economía y Competitividad (SAF2011-22988), and the "Red Temática de Investigación Cooperativa en Cáncer(RTICC)" (RD06/0020/1001) to O. Llorca; the Spanish "Ministerio de Economía y Competitividad" (PI0900268) to P. Sánchez-Corral; the MRC UK (G0701298) to C.L. Harris; and the Spanish "Ministerio de Economía y Competitividad" (PS09/00122) to M. López Trascasa. In addition, this work was supported by a grant from the Autonomous Region of Madrid (S2010/BMD-2316) to S. Rodríguez de Córdoba, O. Llorca, M. López Trascasa, and P. Sánchez-Corral. M.C. Pickering is a Wellcome Trust Senior Fellow in Clinical Science (WT098476MA). H. Yébenes was supported by a postdoctoral contract by the RTICC, and C. Abarrategui-Garrido was supported by the "Fundación de Investigación Biomédica del Hospital Universitario La Paz." ; Peer reviewed

This study analyzed gender balance in the texts and illustrations of three recently published, high school US history textbooks and one alternate volume of American history. In all of the American history texts analyzed there were significantly more males than females in text content and illustrations. These textbooks focused on the contributions of those famous Americans who have been a part of the historical record. The record is skewed with regard to gender, leaving teachers and students with the arduous task of acknowledging the absence of women while attempting to fill in the gaps through their own research and resources. Standards committees and textbook publishers should change their focus and teachers and students should confront gender imbalance by integrating high quality women's history resources into the classroom with web-based resources, family and community history projects, young adult literature, history textbook analysis, and the vision of the C3 Framework.

PurposeIn both elementary schools and elementary teacher education programs, social studies is marginalized while standards require increasingly more ambitious reasoning, reading, and writing in social studies than has historically been documented in American elementary schools. The purpose of this paper is to explain the challenges that elementary social studies teacher educators face in preparing elementary school teachers to facilitate the kind of ambitious social studies envisioned in the NCSS's C3 Framework and advocate an approach to successfully address these challenges.Design/methodology/approachThis paper articulates a targeted and ambitious approach to elementary social studies teacher education. The authors describe five recommendations from the teacher education literature for supporting preservice teachers in learning disciplinary-oriented social studies teaching, recommendations that guided the redesign of the social studies methods course. The authors then highlight key aspects of the redesigned methods course and demonstrate how the authors engaged the challenges inherent in the work of elementary social studies teacher education.FindingsAlthough this paper is not arranged in such a way as to substantiate empirical findings, the purpose of the paper is to demonstrate an approach to elementary social studies education aligned with extant literature on preparing teachers to engage in reform teaching practices, specifically those disciplinary oriented practices suggested in NCSS's C3 Framework. As such, the paper should be read as a perspective on practice.Research limitations/implicationsThe type of disciplinary-oriented approach described here is increasingly under investigation in secondary teacher education research and similar approaches are under investigation in elementary math and science education research. To the authors' knowledge, the approach is novel in elementary social studies education. Furthermore, the authors believe it offers a direction for researchers interested in gaps in the literature related to practice based teacher education and disciplinary-oriented social studies teacher education.Practical implicationsThe approach described here offers specific guidance and resources for teacher educators who are struggling with the challenges of the contemporary social studies education landscape and/or who wish to focus methods courses in disciplinary ways.Social implicationsResearch in social studied education has demonstrated that when students are exposed to disciplinary practices in social studies, their literacy skills improve and they learn analytical skills that support their development as citizens (consumption of media, participation in public discourse, ability to discern arguments).Originality/valueAs noted above, the approach described here is novel in elementary social studies education. Combining a disciplinary approach with a practice-based frame in elementary social studies represents an opportunity for empirical research and offers new approaches to the practice of teacher education and early career professional development.

33 p.-4 fig.-2 fig. supl. ; Complement is an essential component of innate immunity. Its activation results in the assembly of unstable protease complexes, denominated C3/C5 convertases, leading to inflammation and lysis. Regulatory proteins inactivate C3/C5 convertases on host surfaces to avoid collateral tissue damage. On pathogen surfaces, properdin stabilizes C3/C5 convertases to efficiently fight infection. How properdin performs this function is, however, unclear. Using electron microscopy we show that the N-and C-terminal ends of adjacent monomers in properdin oligomers conform a curly vertex that holds together the AP convertase, interacting with both the C345C and vWA domains of C3b and Bb, respectively. Properdin also promotes a large displacement of the TED (thioestercontaining domain) and CUB (complement protein subcomponents C1r/C1s, urchin embryonic growth factor and bone morphogenetic protein 1) domains of C3b, which likely impairs C3-convertase inactivation by regulatory proteins. The combined effect of molecular cross-linking and structural reorganization increases stability of the C3 convertase and facilitates recruitment of fluid-phase C3 convertase to the cell surfaces. Our model explains how properdin mediates the assembly of stabilized C3/C5-convertase clusters, which helps to localize complement amplification to pathogen surfaces. ; This work was funded by the Autonomous Region of Madrid (S2010/BMD-2316 to S.R.d.C. and O.L.), the Ramón Areces Foundation (O.L.), and the Spanish government (SAF2011-22988 to O.L. and SAF2011-26583 to S.R.d.C.). O.L. is additionally supported by Red Temática de Investigación Cooperativa en Cáncer (RD06/0020/1001), and S.R.d.C. is also supported by the Fundación Renal Iñigo Alvarez de Toledo and the Seventh Framework Programme European Union Project EURenOmics (European Consortium for High-Throughput Research in Rare Kidney Diseases-305608). ; Peer Reviewed

Purpose Dysregulation of the complement cascade contributes to a variety of retinal dystrophies, including age-related macular degeneration (AMD). The central component of complement, C3, is expressed in abundance by macrophages in the outer retina, and its ablation suppresses photoreceptor death in experimental photo-oxidative damage. Whether this also influences macrophage reactivity in this model system, however, is unknown. We investigate the effect of C3 ablation on macrophage activity and phagocytosis by outer retinal macrophages during photo-oxidative damage. Methods Age-matched C3 knockout (KO) mice and wild-type (WT) C57/Bl6 mice were subjected to photo-oxidative damage. Measurements of the outer nuclear layer (ONL) thickness and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were used to assess pathology and photoreceptor apoptosis, respectively. Macrophage abundance and phagocytosis were assessed with immunolabeling for pan-macrophage and phagocytic markers, in conjunction with TUNEL staining in cohorts of C3 KO and WT mice. Results The C3 KO mice exhibited protection against photoreceptor cell death following photo-oxidative damage, which was associated with a reduction in immunoreactivity for the stress-related factor GFAP. In conjunction, there was a reduction in IBA1-positive macrophages in the outer retina compared to the WT mice and a decrease in the number of CD68-positive cells in the outer nuclear layer and the subretinal space. In addition, the engulfment of TUNEL-positive and -negative photoreceptors by macrophages was significantly lower in the C3 KO mice cohort following photo-oxidative damage compared to the WT cohort. Conclusions The results show that the absence of C3 mitigates the phagocytosis of photoreceptors by macrophages in the outer retina, and the net impact of C3 depletion is neuroprotective in the context of photo-oxidative damage. These data improve our understanding of the impact of C3 inhibition in subretinal inflammation and inform the development of treatments for targeting complement activation in diseases such as AMD. ; This study was supported by project grants from the National Health and Medical Research Council (APP1165599; APP1127705), Australian National University Translational Fellowship and Australian Government Research Training Program Scholarship.