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Many questions remain unanswered concerning the long-term effects of COVID-19 on children. In this report, we describe a computable phenotyping algorithm for identifying children and adolescents with postacute sequelae of COVID-19 (PASC) and pilot this tool to characterize the clinical epidemiology of pediatric PASC in a large healthcare delivery network.

Semi-structured interviews conducted with 14 spouses of licensed practicing marriage therapists were analyzed using descriptive phenomenology. Participants described benefits that their spouse’s ex...

Drawing on the work of Julianne Newton and other scholars of ethics, this case study in visual ethics explores the cultural phenomenon of viral videos seeking to document instances of “stolen valor,” or the unmasking of individuals who visually portray themselves as affiliated with the Armed Services when they have not earned such recognition. The chapter analyzes the strategic use of public shaming and its manifestation as a dialectical exchange between the accuser and the accused. A typology of shaming videos is offered, including an explanation of the visual ethical markers inherent in these digital presentations. The chapter also discusses the moral panic created by these shaming videos and the attendant political fallout, as a prelude to a discussion of the ethics of digital vigilantism. The moral and ethical implications of video-based public shaming as a response strategy to instances of stolen valor form the foundation of this visual analysis.

The investigation of drinking refusal self-efficacy and alcohol protective behavioral strategies (PBSA) has revealed inconsistent results. Sex may be one factor that plays a role in these results given the demonstrable differences between the alcohol use behaviors of men and women. The current study examined the moderating effects of drinking refusal self-efficacy and sex on the relationships that PBSA subtypes have with alcohol outcomes for traditional age undergraduate students (18–25 years of age; 81% women; 60% White). Results showed negative associations between manner of drinking PBSA and alcohol consumption for individuals with high levels of drinking refusal self-efficacy but not low levels of drinking refusal self-efficacy. However, manner of drinking PBSA was positively associated with alcohol-related negative consequences for men but not for women. Results also showed negative associations between stopping and limiting drinking PBSA and alcohol related negative consequences for individuals with high levels of drinking refusal self-efficacy but not low levels of drinking refusal self-efficacy. It appears that addressing drinking refusal self-efficacy within the context of PBSA is valuable for traditional college students.

Background Children are the most likely population to get influenza, and are two times more likely compared to adults aged 65 and greater (attack rate by age group: 0-17 yo 9.3%, 18-74 yo 8.8%, 65 + 3.9%). Additionally, children are at high risk of suffering complications from influenza. According to the CDC, the overall effectiveness of the 2018-2019 flu vaccine for both strains A and B was 48% in children aged 6m-8 years and 7% in children aged 9- 17 years. Currently our Pediatric Emergency Department (PED) does not routinely offer influenza vaccine to unvaccinated patients. Our project goals are to identify barriers to the administration of influenza vaccine in the PED and to offer and administer influenza vaccine to eligible patients. Methods After performing root cause analysis with key stakeholders, the first countermeasure implemented in a Plan-Do-Study Act (PDSA) cycle was the development of a screening form including eligibility criteria, history of influenza vaccine, consent for vaccine or reason for declining vaccine. The screening form was administered by resident physicians in our PED from October to November who then went on to order the vaccine for eligible patients who consented. Primary outcome measures included number of patients screened per month, percent of patients who desired the vaccine, and the percent of patients who received the vaccine in the ED during their visit. Secondary outcome measures included length of PED stay. Results Preliminary results show that 75% (42/56,CI: 62%-86%) of children screened in the PED between October and November were eligible for the influenza vaccine. Of those eligible, 59% (29/42, CI: 43%-74%) received the vaccine. The average length of stay was comparable between those that received influenza vaccine and those that did not (p value 0.4756). Conclusion A subset of eligible patients are now being offered and receiving the flu shot in our PED. Over half of eligible patients received the influenza vaccine, demonstrating that a resident administered screening form has been a successful countermeasure for increasing vaccine rates. Future PDSA cycles will focus on further increasing the number of patients screened and capturing patients who consented but did not receive vaccine. Disclosures All Authors: No reported disclosures

Summary A unique population of Foxp3 + CD4 + regulatory T (Treg) cells, with a distinct transcriptome and antigen-receptor repertoire, resides in visceral adipose tissue (VAT) of lean individuals. These cells regulate local inflammation and both local and systemic metabolic indices. Here we focus on expansion of the VAT Treg compartment in aging lean mice—assessing these cells' phenotypic conversion from conventional CD4 + T cells, influx from lymphoid organs, and local population dynamics. Our findings establish that the VAT Treg compartment is seeded from thymocytes generated during the first weeks of life and expands beyond 10 weeks of age due to indolent proliferation, of certain clones in particular, coupled with enhanced survival. Accumulation of VAT Tregs depends on the antigen(s) presented by MHC class-II molecules and soluble mediators, notably interleukin(IL)-33. Addressing such factors therapeutically promises novel approaches for harnessing Tregs to stem the growing epidemic of obesity and consequent metabolic abnormalities.

SummaryThe regenerative capacity of the peripheral nervous system declines with age. Why this occurs, however, is unknown. We demonstrate that 24-month-old mice exhibit an impairment of functional recovery after nerve injury compared to 2-month-old animals. We find no difference in the intrinsic growth capacity between aged and young sensory neurons in vitro or in their ability to activate growth-associated transcriptional programs after injury. Instead, using age-mismatched nerve transplants in vivo, we show that the extent of functional recovery depends on the age of the nerve graft, and not the age of the host. Molecular interrogation of the sciatic nerve reveals that aged Schwann cells (SCs) fail to rapidly activate a transcriptional repair program after injury. Functionally, aged SCs exhibit impaired dedifferentiation, myelin clearance, and macrophage recruitment. These results suggest that the age-associated decline in axonal regeneration results from diminished Schwann cell plasticity, leading to slower myelin clearance.

Ligand-dependent actions of the vitamin D receptor (VDR) play a pleiotropic role in the regulation of innate and adaptive immunity. The liganded VDR is required for recruitment of macrophages during the inflammatory phase of cutaneous wound healing. Although the number of macrophages in the granulation tissue 2 days after wounding is markedly reduced in VDR knockout (KO) compared with wild-type mice, VDR ablation does not alter macrophage polarization. Parabiosis studies demonstrate that circulatory chimerism with wild-type mice is unable to rescue the macrophage defect in the wounds of VDR KO mice and reveal that wound macrophages are of local origin, regardless of VDR status. Wound cytokine analyses demonstrated a decrease in macrophage colony-stimulating factor (M-CSF) protein levels in VDR KO mice. Consistent with this, induction of M-CSF gene expression by TGFβ and 1,25-dihydroxyvitamin D was impaired in dermal fibroblasts isolated from VDR KO mice. Because M-CSF is important for macrophage self-renewal, studies were performed to evaluate the response of tissue resident macrophages to this cytokine. A decrease in M-CSF induced proliferation and cyclin D1 expression was observed in peritoneal resident macrophages isolated from VDR KO mice, suggesting an intrinsic macrophage abnormality. Consistent with this, wound-healing assays in mice with macrophage-specific VDR ablation demonstrate that a normal wound microenvironment cannot compensate for the absence of the VDR in macrophages and thus confirm a critical role for the macrophage VDR in the inflammatory response to injury.

Apoptosis is a key tumor suppression mechanism that can be initiated by activation of the proapoptotic factor Bax. The Ku70 DNA end-joining protein has recently been shown to suppress apoptosis by sequestering Bax from mitochondria. The mechanism by which Bax is regulated remains unknown. Here, we identify eight lysines in Ku70 that are targets for acetylation in vivo. Five of these, K539, K542, K544, K533, and K556, lie in the C-terminal linker domain of Ku70 adjacent to the Bax interaction domain. We show that CBP and PCAF efficiently acetylate K542 in vitro and associate with Ku70 in vivo. Mimicking acetylation of K539 or K542 or treating cells with deacetylase inhibitors abolishes the ability of Ku70 to suppress Bax-mediated apoptosis. We demonstrate that increased acetylation of Ku70 disrupts the Ku70-Bax interaction and coincides with cytoplasmic accumulation of CBP. These results shed light on the role of acetyltransferases as tumor suppressors.

Ischemic preconditioning is the phenomenon whereby brief periods of sublethal ischemia protect against a subsequent, more prolonged, ischemic insult. In remote ischemic preconditioning (RIPC), ischemia to one organ protects others organs at a distance. We created mouse models to ask if inhibition of the alpha-ketoglutarate (αKG)-dependent dioxygenase Egln1, which senses oxygen and regulates the hypoxia-inducible factor (HIF) transcription factor, could suffice to mediate local and remote ischemic preconditioning. Using somatic gene deletion and a pharmacological inhibitor, we found that inhibiting Egln1 systemically or in skeletal muscles protects mice against myocardial ischemia-reperfusion (I/R) injury. Parabiosis experiments confirmed that RIPC in this latter model was mediated by a secreted factor. Egln1 loss causes accumulation of circulating αKG, which drives hepatic production and secretion of kynurenic acid (KYNA) that is necessary and sufficient to mediate cardiac ischemic protection in this setting., Broad Institute of MIT and Harvard. SPARC Program, Burroughs Wellcome Fund

Severe pulmonary arterial hypertension (PAH) occurs in idiopathic form and in association with diverse diseases. The pathological hallmarks are distal smooth muscle hypertrophy, obliteration of small pulmonary arteriole lumens, and disorganized cellular proliferation in plexiform lesions. In situ thrombosis is also observed. A detailed understanding of the disease progression has been hampered by the absence of an animal model bearing all the pathological features of human disease. To create a model with these characteristics, we gave young (200-g) rats monocrotaline 1 wk following left pneumonectomy; controls with vehicle treatment or sham operation were also studied. In experimental rats, pulmonary arteries had distal smooth muscle hypertrophy and proliferative perivascular lesions. The lesions had a plexiform appearance, occurred early in disease development, and were composed of cells expressing endothelial antigens. Three-dimensional microangiography revealed severe vascular pruning and disorganized vascular networks. We found that expression of tissue factor (TF), the membrane glycoprotein that initiates coagulation, facilitates angiogenesis, and mediates arterial injury in the systemic circulation, was increased in the pulmonary arterioles and plexiform-like lesions of the rats. TF was also heavily expressed in the vessels and plexiform lesions of humans with pulmonary arterial hypertension. We conclude that plexiform-like lesions can be reproduced in rats, and this model will facilitate experiments to address controversies about the role of these lesions in PAH. Increased TF expression may contribute to the prothrombotic diathesis and vascular cell proliferation typical of human disease.

The thymus reaches its maximum size early in life and then begins to shrink, producing fewer T cells with increasing age. This thymic decline is thought to contribute to age-related T cell lymphopenias and hinder T cell recovery following bone marrow transplantation. While several cellular and molecular processes have been implicated in age-related thymic involution, their relative contributions are not known. Using heterochronic parabiosis, we observe that young circulating factors are not sufficient to drive regeneration of the aged thymus. In contrast, we find that resupplying young, engraftable thymic epithelial cells to a middle-aged or defective thymus leads to thymic growth and increased T cell production. Intrathymic transplantation and in vitro colony forming assays reveal that the engraftment and proliferative capacities of thymic epithelial cells diminish early in life, whereas the receptivity of the thymus to thymic epithelial cell engraftment remains relatively constant with age. These results support a model in which thymic growth and subsequent involution are driven by cell intrinsic changes in the proliferative capacity of thymic epithelial cells, and further show that young thymic epithelial cells can engraft and directly drive the growth of involuted thymuses.

Help the Aged Muscle function declines with age, as does neurogenesis in certain brain regions. Two teams analyzed the effects of heterochronic parabiosis in mice. Sinha et al. (p. 649 ) found that when an aged mouse shares a circulatory system with a youthful mouse, the aged mouse sees improved muscle function, and Katsimpardi et al. (p. 630 ) observed increased generation of olfactory neurons. In both cases, Growth Differentiation Factor 11 appeared to be one of the key components of the young blood.

SummaryThe most common form of heart failure occurs with normal systolic function and often involves cardiac hypertrophy in the elderly. To clarify the biological mechanisms that drive cardiac hypertrophy in aging, we tested the influence of circulating factors using heterochronic parabiosis, a surgical technique in which joining of animals of different ages leads to a shared circulation. After 4 weeks of exposure to the circulation of young mice, cardiac hypertrophy in old mice dramatically regressed, accompanied by reduced cardiomyocyte size and molecular remodeling. Reversal of age-related hypertrophy was not attributable to hemodynamic or behavioral effects of parabiosis, implicating a blood-borne factor. Using modified aptamer-based proteomics, we identified the TGF-β superfamily member GDF11 as a circulating factor in young mice that declines with age. Treatment of old mice to restore GDF11 to youthful levels recapitulated the effects of parabiosis and reversed age-related hypertrophy, revealing a therapeutic opportunity for cardiac aging.PaperFlick

Myeloid sarcomas are extramedullary accumulations of immature myeloid cells that may present with or without evidence of pathologic involvement of the bone marrow or peripheral blood, and often coincide with or precede a diagnosis of acute myeloid leukemia (AML). A dearth of experimental models has hampered the study of myeloid sarcomas and led us to establish a new system in which tumor induction can be evaluated in an easily accessible non-hematopoietic tissue compartment. Using ex-vivo transduction of oncogenic Kras(G12V) into p16/p19(-/-) bone marrow cells, we generated transplantable leukemia-initiating cells that rapidly induced tumor formation in the skeletal muscle of immunocompromised NOD.SCID mice. In this model, murine histiocytic sarcomas, equivalent to human myeloid sarcomas, emerged at the injection site 30-50 days after cell implantation and consisted of tightly packed monotypic cells that were CD48+, CD47+ and Mac1+, with low or absent expression of other hematopoietic lineage markers. Tumor cells also infiltrated the bone marrow, spleen and other non-hematopoietic organs of tumor-bearing animals, leading to systemic illness (leukemia) within two weeks of tumor detection. P16/p19(-/-); Kras(G12V) myeloid sarcomas were multi-clonal, with dominant clones selected during secondary transplantation. The systemic leukemic phenotypes exhibited by histiocytic sarcoma-bearing mice were nearly identical to those of animals in which leukemia was introduced by intravenous transplantation of the same donor cells. Moreover, murine histiocytic sarcoma could be similarly induced by intramuscular injection of MLL-AF9 leukemia cells. This study establishes a novel, transplantable model of murine histiocytic/myeloid sarcoma that recapitulates the natural progression of these malignancies to systemic disease and indicates a cell autonomous leukemogenic mechanism.

Soft-tissue sarcomas are heterogeneous cancers that can present with tissue-specific differentiation markers. To examine the cellular basis for this histopathological variation and to identify sarcoma-relevant molecular pathways, we generated a chimeric mouse model in which sarcoma-associated genetic lesions can be introduced into discrete, muscle-resident myogenic and mesenchymal cell lineages. Expression of Kirsten rat sarcoma viral oncogene [ Kras ( G12V )] and disruption of cyclin-dependent kinase inhibitor 2A ( CDKN2A ; p16p19 ) in prospectively isolated satellite cells gave rise to pleomorphic rhabdomyosarcomas (MyoD-, Myogenin- and Desmin-positive), whereas introduction of the same oncogenetic hits in nonmyogenic progenitors induced pleomorphic sarcomas lacking myogenic features. Transcriptional profiling demonstrated that myogenic and nonmyogenic Kras; p16p19 null sarcomas recapitulate gene-expression signatures of human rhabdomyosarcomas and identified a cluster of genes that is concordantly up-regulated in both mouse and human sarcomas. This cluster includes genes associated with Ras and mechanistic target of rapamycin (mTOR) signaling, a finding consistent with activation of the Ras and mTOR pathways both in Kras; p16p19 null sarcomas and in 26–50% of human rhabdomyosarcomas surveyed. Moreover, chemical inhibition of Ras or mTOR signaling arrested the growth of mouse Kras; p16p19 null sarcomas and of human rhabdomyosarcoma cells in vitro and in vivo. Taken together, these data demonstrate the critical importance of lineage commitment within the tumor cell-of-origin in determining sarcoma histotype and introduce an experimental platform for rapid dissection of sarcoma-relevant cellular and molecular events.

This article explores the assumptions about science and technology held by the engineers who attempted to delay the launch of the Challenger space shuttle. These assumptions, it is argued, affected the ways in which the engineers framed the arguments used to persuade managers not to launch. Examining the decision making processes prior to the tragedy reveals three dominant conceptions of science and technology which guided the engineers' persuasive efforts, and which appear to account for why the engineers did not succeed in their attempt to influence the managers.

A major cause of aging is thought to result from the cumulative effects of cell loss over time. In yeast, caloric restriction (CR) delays aging by activating the Sir2 deacetylase. Here we show that expression of mammalian Sir2 (SIRT1) is induced in CR rats as well as in human cells that are treated with serum from these animals. Insulin and insulin-like growth factor 1 (IGF-1) attenuated this response. SIRT1 deacetylates the DNA repair factor Ku70, causing it to sequester the proapoptotic factor Bax away from mitochondria, thereby inhibiting stress-induced apoptotic cell death. Thus, CR could extend life-span by inducing SIRT1 expression and promoting the long-term survival of irreplaceable cells.

10029 Background: Soft-tissue sarcomas are heterogeneous malignancies of mesodermal, non-hematopoietic origin. They may present with tissue-specific differentiation, such as myogenic features in rhabdomyosarcoma. However, the cellular origins of sarcomas in skeletal muscle have remained controversial. This study sought to investigate the effects of cell context on the outcome of sarcoma-associated genetic lesions by ex-vivo genetic perturbation and orthotopic implantation of muscle satellite cells (sorted as CD45(-)MAC1(-)TER119(-)Sca1(-)β1-integrin(+)CXCR4(+) cells) and non-myogenic precursors (sorted as CD45(-)MAC1(-)TER119(-)Sca1(+) cells), freshly isolated by fluorescence-activated cell sorting from p16p19(null)mouse skeletal muscle, infected with Kras(G12V)-pGIPZ-IRES-GFP lentivirus, and injected into the gastrocnemius muscles of immunocompromised NOD.SCID mice. We show that mouse Kras-expressing; p16p19(null) muscle satellite cells can serve as cells-of-origin for mouse rhabdomyosarcomas (MyoD, Myogenin and Desmin positive) with non-alveolar, pleomorphic features. Conversely, Kras-expressing; p16p19(null) non-myogenic progenitors typically induce non-myogenic, pleomorphic sarcomas (MyoD, Myogenin and Desmin negative). Despite initiation in distinct cells-of-origin, Kras; p16p19(null) sarcomas share a common, Ras-predominated transcriptional signature that is enriched in human soft-tissue sarcomas and suggests that Ras-pathway activation is an important event in human sarcomas. Moreover, our bioinformatic analyses identify a small group of genes that are upregulated in sarcomas across species and may hold broad therapeutic relevance. In summary, we have established a highly tractable chimeric mouse model for the induction of sarcomas in skeletal muscle, which demonstrates that the lineage commitment of the target cell into which oncogenetic hits are introduced is critical in determining sarcoma phenotype. This new sarcoma model recapitulates genetic events in human soft-tissue sarcomas, can be used as a platform to dissect the cellular and genetic events responsible for sarcoma development and may accelerate future therapeutic discovery efforts in the sarcoma field.

This study was undertaken to evaluate the precision and sensitivity of three different commercial APTT reagents containing the activators kaolin, micronized silica, or ellagic acid. These reagents varied greatly in their ability to detect mild coagulopathies. The ellagic acid reagent was able to detect the mildest deficiencies for the most common coagulopathies. This reagent was sensitive to 50% levels of Factor VIIIC, whereas the APTT with the kaolin reagent was not prolonged until levels of 35% or less were attained. The micronized silica reagent was the least sensitive to Factor IX deficiency, detecting levels of 12% or less. Precision was similar for all reagents when tested with normal and slightly abnormal plasmas. Since methods and instrumentation vary, each laboratory should evaluate their APTT reagent to determine its precision and sensitivity.

(1985). The Effect of the loss of copyright privilege on Glasgow University library, 1790–1858. Library History: Vol. 7, No. 2, pp. 45-57.