314 research outputs found
Tracking and ablating subpopulations of epiblast cells in the chick embryo
The early chick embryo contains subpopulations of cells that express lineage-specific transcription factors. We have developed protocols to examine the role of these cells during development that involve labeling them for cell tracking purposes and ablating them within the epiblast. The procedures take advantage of the fact that subpopulations of epiblast cells differentially express cell surface antigens recognized by monoclonal antibodies. Embryos are removed from the shell and incubated on the yolk with an antibody. Cells that bind the antibody are either tagged with a fluorescent secondary antibody or lysed with complement. For long-term analyses, embryos are returned to a host shell and placed in an incubator. This method of whole embryo manipulation ex-ovo and incubation in-ovo supports normal development into the fetal period
National identity and conversion through medieval romance : The case of Hrafn Gunnlaugsson's film "ĂŤ skugga hrafnsins" (In the shadow of the raven)
Blending elements of Icelandic saga (Njal's Saga, Laxdaela Saga) and late medieval Arthurian romance (the Icelandic version of the Tristan legend), director Hrafn Gunnlaugsson troubles the question of heroic allegiance in relation to national identity, religion (Christianity as opposed to belief in the northern gods), and romantic love through the family feud of his hero Trausti in "I skugga Hrafnsins." That is, Trausti returns to Iceland from training in Norway as a priest to assume the role of head of his family, which is embroiled in a conflict with another clan over a dead whale; his adversary in the dispute is Isold, daughter of Erikur and unmarried mother pledged to the son of the bishop of Iceland. The priority of conflicting claims – the pagan heroic code of vengeance, familial obligation, and fate versus Christian mercy, obligation to God, and individual will – is traced against a backdrop of claims of national identity versus the monolithic blurring of boundaries demanded by the dominance of the Church. All of the issues, conventionally debated in the Middle Ages within the genre of the saga on the one hand and the romance on the other, are complicated in the film by the romance's courtly-love context of attraction of mortal enemies Isold and Trausti. The inversion of the two genres within a contemporary film (1988) provides a uniquely Icelandic perspective on the relationship of the present to tradition, history, and the past – and the probing question of boundaries and transgressions, for the individual and for nation
Recommended from our members
Club-like cells in proliferative inflammatory atrophy of the prostate.
Club cells are a type of bronchiolar epithelial cell that serve a protective role in the lung and regenerate damaged lung epithelium. Single-cell RNA sequencing (scRNA-seq) of young adult human prostate and urethra identified cell populations in the prostatic urethra and collecting ducts similar in morphology and transcriptomic profile to lung club cells. We further identified club cell-like epithelial cells by scRNA-seq of prostate peripheral zone tissues. Here, we aimed to identify and spatially localize club cells in situ in the prostate, including in the peripheral zone. We performed chromogenic RNA in situ hybridization for five club cell markers (CP, LTF, MMP7, PIGR, SCGB1A1) in a series of (1) nondiseased organ donor prostate and (2) radical prostatectomy specimens from individuals with prostate cancer. We report that expression of club cell genes in the peripheral zone is associated with inflammation and limited to luminal epithelial cells classified as intermediate cells in proliferative inflammatory atrophy (PIA). Club-like cells were enriched in radical prostatectomy specimens compared to nondiseased prostates and associated with high-grade prostate cancer. We previously reported that luminal epithelial cells in PIA can rarely harbor oncogenic TMPRSS2:ERG (ERG+) gene fusions, and we now demonstrate that club cells are present in association with ERG+ PIA that is transitioning to early adenocarcinoma. Finally, prostate epithelial organoids derived from prostatectomy specimens demonstrate that club-like epithelial cells can be established in organoids and are sensitive to anti-androgen-directed treatment in vitro in terms of decreased androgen signaling gene expression signatures compared to basal or hillock cells. Overall, our study identifies a population of club-like cells in PIA and proposes that these cells play an analogous role to that of club cells in bronchiolar epithelium. Our results further suggest that inflammation drives lineage plasticity in the human prostate and that club cells in PIA may be prone to oncogenic transformation. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland
It isn’t just Mom: Gendered provision of family and home responsibilities among emerging adults during COVID-19
Media and research reports have highlighted the disproportionate burden of home and family responsibilities shouldered by women and mothers due to COVID-19-related school/childcare shutdowns. This cross-sectional study extends this line of inquiry to emerging adults. Our study of 329 diverse emerging adults suggests that young women took on more home/family responsibilities than young men amidst the pandemic, and that these duties were associated with symptoms of depression. However, results also indicate that emerging adults who reported greater home/family responsibilities amidst the pandemic also experienced more quality family time, suggesting that pandemic-related challenges may have also been accompanied by opportunities for family connection. Contrary to previous research that has shown home/family responsibilities to be concentrated by SES and race/ethnicity, we found that participants uniformly endorsed COVID-19-related impacts on home/family responsibilities across these demographic distinctions. This could reflect the ubiquity of COVID-19’s impact; across race/ethnicity and class—but differentially by gender—young adults faced significant challenges in taking on new home/family roles
Myo/Nog cell regulation of bone morphogenetic protein signaling in the blastocyst is essential for normal morphogenesis and striated muscle lineage specification
AbstractCells that express MyoD mRNA, the G8 antigen and the bone morphogenetic protein (BMP) inhibitor noggin (Nog) are present in the epiblast before gastrulation. Ablation of “Myo/Nog” cells in the blastocyst results in an expansion of canonical BMP signaling and prevents the expression of noggin and follistatin before and after the onset of gastrulation. Once eliminated in the epiblast, they are neither replaced nor compensated for as development progresses. Older embryos lacking Myo/Nog cells exhibit severe axial malformations. Although Wnts and Sonic hedgehog are expressed in ablated embryos, skeletal muscle progenitors expressing Pax3 are missing in the somites. Pax3+ cells do emerge adjacent to Wnt3a+ cells in vitro; however, few undergo skeletal myogenesis. Ablation of Myo/Nog cells also results in ectopically placed cardiac progenitors and cardiomyocytes in the somites. Reintroduction of Myo/Nog cells into the epiblast of ablated embryos restores normal patterns of BMP signaling, morphogenesis and skeletal myogenesis, and inhibits the expression of cardiac markers in the somites. This study demonstrates that Myo/Nog cells are essential regulators of BMP signaling in the early epiblast and are indispensable for normal morphogenesis and striated muscle lineage specification
USA WOMENS RUGBY SEVENS CONTACT INJURY RISK FACTORS
The purpose of the study was to identify the rates and causes of contact injuries in U.S. women’s Rugby-7s tournament players (2010-2015) and present guidelines for injury prevention to reduce the risk of injury in this emerging female contact-sport athlete. Data were captured using the Rugby Injury Survey & Evaluation (RISE) methodology. Contact injuries were frequent over the study period (direct=56%; indirect=38%, unknown=6%). Contact injuries overall were similar among positions (
BIOMECHANICAL CONTACT INJURY INFLUENCES IN USA MENS RUGBY-7S
The aim of this study was to prospectively report injury incidence and contact mechanisms in U.S. men’s under-19 to elite Rugby-7s players (n=852) over 2010-2015, using the Rugby Injury Survey & Evaluation (RISE) methodology. Contact injuries occurred with frequency (Overall, including time-loss and medical attention=55.4/1000ph; time-loss=17.2/1000ph;
Depletion of Myo/Nog Cells in the Lens Mitigates Posterior Capsule Opacification in Rabbits.
Purpose: Posterior capsule opacification (PCO) is a vision-impairing disease that occurs in some adults and most children after cataract surgery. Contractile myofibroblasts contribute to PCO by producing wrinkles in the lens capsule that scatter light. Myofibroblasts in the lens originate from Myo/Nog cells named for their expression of the MyoD transcription factor and bone morphogenetic protein inhibitor noggin. In this study we tested the effects of depleting Myo/Nog cells on development of PCO.
Methods: Myo/Nog cells were eliminated by injecting the G8 antibody conjugated to 3DNA nanocarriers for the cytotoxin doxorubicin (G8:3DNA:Dox) during cataract surgery in rabbits. The severity of PCO was scored by slit lamp analysis, gross and histologic observation, and immunofluorescence localization of α-smooth muscle actin.
Results: G8:3DNA:Dox specifically induced cell death in Myo/Nog cells in the lens. None of the lenses administered G8:3DNA containing 9 to 36 ÎĽM doxorubicin developed greater than trace levels of central PCO and few myofibroblasts were present on the capsule. Less than 9% of these lenses exhibited greater than mild levels of peripheral PCO. Doxorubucin itself reduced PCO; however, myofibroblasts and wrinkles were abundant in the lens, and off-target effects were observed in the ciliary processes and cornea.
Conclusions: Myo/Nog cells are the primary source of myofibroblasts in the lens after cataract surgery. Targeted depletion of Myo/Nog cells has potential for preventing PCO and preserving vision
Brain-specific angiogenesis inhibitor 1 is expressed in the Myo/Nog cell lineage.
The Myo/Nog cell lineage was discovered in the chick embryo and is also present in adult mammalian tissues. The cells are named for their expression of mRNA for the skeletal muscle specific transcription factor MyoD and bone morphogenetic protein inhibitor Noggin. A third marker for Myo/Nog cells is the cell surface molecule recognized by the G8 monoclonal antibody (mAb). G8 has been used to detect, track, isolate and kill Myo/Nog cells. In this study, we screened a membrane proteome array for the target of the G8 mAb. The array consisted of \u3e5,000 molecules, each synthesized in their native confirmation with appropriate post-translational modifications in a single clone of HEK-293T cells. G8 mAb binding to the clone expressing brain-specific angiogenesis inhibitor 1 (BAI1) was detected by flow cytometry, re-verified by sequencing and validated by transfection with the plasmid construct for BAI1. Further validation of the G8 target was provided by enzyme-linked immunosorbent assay. The G8 epitope was identified by screening a high-throughput, site directed mutagenesis library designed to cover 95-100% of the 954 amino acids of the extracellular domain of the BAI1 protein. The G8 mAb binds within the third thrombospondin repeat of the extracellular domain of human BAI1. Immunofluorescence localization experiments revealed that G8 and a commercially available BAI1 mAb co-localize to the subpopulation of Myo/Nog cells in the skin, eyes and brain. Expression of the multi-functional BAI1 protein in Myo/Nog cells introduces new possibilities for the roles of Myo/Nog cells in normal and diseased tissues
Recommended from our members
Sustainable Development in Surgery: The Health, Poverty, and Equity Impacts of Charitable Surgery in Uganda
Background. The recently adopted Sustainable Development Goals call for the end of poverty and the equitable provision of healthcare. These goals are often at odds, however: health seeking can lead to catastrophic spending, an outcome for which cancer patients and the poor in resource-limited settings are at particularly high risk. How various health policies affect the additional aims of financial wellbeing and equity is poorly understood. This paper evaluates the health, financial, and equity impacts of governmental and charitable policies for surgical oncology in a resource-limited setting.
Methods. Three charitable platforms for surgical oncology delivery in Uganda were compared to six governmental policies aimed at improving healthcare access. An extended cost-effectiveness analysis using an agent-based simulation model examined the numbers of lives saved, catastrophic expenditure averted, impoverishment averted, costs, and the distribution of benefits across the wealth spectrum.
Findings. Of the nine policies and platforms evaluated, two were able to provide simultaneous health and financial benefits efficiently and equitably: mobile surgical units and governmental policies that simultaneously address surgical scaleup, the cost of surgery, and the cost of transportation. Policies that only remove user fees are dominated, as is the commonly employed short-term “surgical mission trip”. These results are robust to scenario and sensitivity analyses.
Interpretation. The most common platforms for increasing access to surgical care appear unable to provide health and financial risk protection equitably. On the other hand, mobile surgical units, to date an underutilized delivery platform, are able to deliver surgical oncology in a manner that meets sustainable development goals by improving health, financial solvency, and equity. These platforms compare favorably with policies that holistically address surgical delivery and should be considered as countries strengthen health systems
- …