526 research outputs found

    Avian cerebellar floccular fossa size is not a proxy for flying ability in birds

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    Extinct animal behavior has often been inferred from qualitative assessments of relative brain region size in fossil endocranial casts. For instance, flight capability in pterosaurs and early birds has been inferred from the relative size of the cerebellar flocculus, which in life protrudes from the lateral surface of the cerebellum. A primary role of the flocculus is to integrate sensory information about head rotation and translation to stabilize visual gaze via the vestibulo-occular reflex (VOR). Because gaze stabilization is a critical aspect of flight, some authors have suggested that the flocculus is enlarged in flying species. Whether this can be further extended to a floccular expansion in highly maneuverable flying species or floccular reduction in flightless species is unknown. Here, we used micro computed-tomography to reconstruct “virtual” endocranial casts of 60 extant bird species, to extract the same level of anatomical information offered by fossils. Volumes of the floccular fossa and entire brain cavity were measured and these values correlated with four indices of flying behavior. Although a weak positive relationship was found between floccular fossa size and brachial index, no significant relationship was found between floccular fossa size and any other flight mode classification. These findings could be the result of the bony endocranium inaccurately reflecting the size of the neural flocculus, but might also reflect the importance of the flocculus for all modes of locomotion in birds. We therefore conclude that the relative size of the flocculus of endocranial casts is an unreliable predictor of locomotor behavior in extinct birds, and probably also pterosaurs and non-avian dinosaurs

    An RNA editing fingerprint of cancer stem cell reprogramming

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    BackgroundDeregulation of RNA editing by adenosine deaminases acting on dsRNA (ADARs) has been implicated in the progression of diverse human cancers including hematopoietic malignancies such as chronic myeloid leukemia (CML). Inflammation-associated activation of ADAR1 occurs in leukemia stem cells specifically in the advanced, often drug-resistant stage of CML known as blast crisis. However, detection of cancer stem cell-associated RNA editing by RNA sequencing in these rare cell populations can be technically challenging, costly and requires PCR validation. The objectives of this study were to validate RNA editing of a subset of cancer stem cell-associated transcripts, and to develop a quantitative RNA editing fingerprint assay for rapid detection of aberrant RNA editing in human malignancies.MethodsTo facilitate quantification of cancer stem cell-associated RNA editing in exons and intronic or 3'UTR primate-specific Alu sequences using a sensitive, cost-effective method, we established an in vitro RNA editing model and developed a sensitive RNA editing fingerprint assay that employs a site-specific quantitative PCR (RESSq-PCR) strategy. This assay was validated in a stably-transduced human leukemia cell line, lentiviral-ADAR1 transduced primary hematopoietic stem and progenitor cells, and in primary human chronic myeloid leukemia stem cells.ResultsIn lentiviral ADAR1-expressing cells, increased RNA editing of MDM2, APOBEC3D, GLI1 and AZIN1 transcripts was detected by RESSq-PCR with improved sensitivity over sequencing chromatogram analysis. This method accurately detected cancer stem cell-associated RNA editing in primary chronic myeloid leukemia samples, establishing a cancer stem cell-specific RNA editing fingerprint of leukemic transformation that will support clinical development of novel diagnostic tools to predict and prevent cancer progression.ConclusionsRNA editing quantification enables rapid detection of malignant progenitors signifying cancer progression and therapeutic resistance, and will aid future RNA editing inhibitor development efforts

    Rural Parent\u27s Experiences of Stress and Resilience During the COVID-19 Pandemic and School Closure

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    The COVID-19 pandemic has generated social and economic disruptions, resulting in cascading effects on the health and well-being of global citizens. However, little research has focused on how COVID-19 has affected rural regions, despite rurality being a critical factor for understanding community impact and response to the pandemic. The purpose of this phenomenological study was to explore the experiences of rural Nebraskan parents with young children during the COVID-19 pandemic and school shutdown, and the strategies they used to support their families during that time. We conducted individual and group interviews with 22 white, non-Hispanic mothers living in rural towns, villages, and farms in the Great Plains region of the United States. Thematic analysis was used to generate the following themes related to pandemic challenges: Impacts on Children’s Education and Development, Impact on Parent’s Work, and Social-emotional Impacts. Additionally, we generated themes related to the ways that rural parents responded to those challenges: Successful Parenting Strategies, Children’s Strategies, Using Community Provided Resources, Finding Unexpected Benefits, and Hope. This study is meaningful because it documented the impact of the COVID-19 pandemic and school shutdown on rural families with young children, and their responses to pandemic-related stressors. Our findings provide further insights into families’ experiences of how COVID-19 affected their lives. Limitations and future directions are also discussed

    Phocine Distemper Virus in Northern Sea Otters in the Pacific Ocean, Alaska, USA

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    Phocine distemper virus (PDV) has caused 2 epidemics in harbor seals in the Atlantic Ocean but had never been identified in any Pacific Ocean species. We found that northern sea otters in Alaska are infected with PDV, which has created a disease threat to several sympatric and decreasing Pacific marine mammals

    Ontogenetic scaling of fore- and hind limb posture in wild chacma baboons (Papio hamadryas ursinus)

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    Sherpa Romeo green journal: open accessLarge-scale interspecific studies of mammals ranging between 0.04–280 kg have shown that larger animals walk with more extended limb joints. Within a taxon or clade, however, the relationship between body size and joint posture is less straightforward. Factors that may affect the lack of congruence between broad and narrow phylogenetic analyses of limb kinematics include limited sampling of (1) ranges of body size, and/or (2) numbers of individuals. Unfortunately, both issues are inherent in laboratory-based or zoo locomotion research. In this study, we examined the relationship between body mass and elbow and knee joint angles (our proxies of fore- and hind limb posture, respectively) in a cross-sectional ontogenetic sample of wild chacma baboons (Papio hamadryas ursinus) habituated in the De Hoop Nature Reserve, South Africa. Videos were obtained from 33 individuals of known age (12 to $108 months) and body mass (2–29.5 kg) during walking trials. Results show that older, heavier baboons walk with significantly more extended knee joints but not elbow joints. This pattern is consistent when examining only males, but not within the female sample. Heavier, older baboons also display significantly less variation in their hind limb posture compared to lighter, young animals. Thus, within this ontogenetic sample of a single primate species spanning an order of magnitude in body mass, hind limb posture exhibited a postural scaling phenomenon while the forelimbs did not. These findings may further help explain 1) why younger mammals (including baboons) tend to have relatively stronger bones than adults, and 2) why humeri appear relatively weaker than femora (in at least baboons). Finally, this study demonstrates how field-acquired kinematics can help answer fundamental biomechanical questions usually addressed only in animal gait laboratories.Ye

    'Against the World': Michael Field, female marriage and the aura of amateurism'

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    This article considers the case of Katherine Bradley and Edith Cooper, an aunt and niece who lived and wrote together as ‘Michael Field’ in the fin-de-siècle Aesthetic movement. Bradley’s bold statement that she and Cooper were ‘closer married’ than the Brownings forms the basis for a discussion of their partnership in terms of a ‘female marriage’, a union that is reflected, as I will argue, in the pages of their writings. However, Michael Field’s exclusively collaborative output, though extensive, was no guarantee for success. On the contrary, their case illustrates the notion, valid for most products of co-authorship, that the jointly written work is always surrounded by an aura of amateurism. Since collaboration defied the ingrained notion of the author as the solitary producer of his or her work, critics and readers have time and again attempted to ‘parse’ the collaboration by dissecting the co-authored work into its constituent halves, a treatment that the Fields too failed to escape

    Lewy Body Dementia Association\u27s Research Centers of Excellence Program: Inaugural Meeting Proceedings

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    The first Lewy Body Dementia Association (LBDA) Research Centers of Excellence (RCOE) Investigator\u27s meeting was held on December 14, 2017, in New Orleans. The program was established to increase patient access to clinical experts on Lewy body dementia (LBD), which includes dementia with Lewy bodies (DLB) and Parkinson\u27s disease dementia (PDD), and to create a clinical trials-ready network. Four working groups (WG) were created to pursue the LBDA RCOE aims: (1) increase access to high-quality clinical care, (2) increase access to support for people living with LBD and their caregivers, (3) increase knowledge of LBD among medical and allied (or other) professionals, and (4) create infrastructure for a clinical trials-ready network as well as resources to advance the study of new therapeutics

    ADIPOR1 is essential for vision and its RPE expression is lost in the Mfrp

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    The knockout (KO) of the adiponectin receptor 1 (AdipoR1) gene causes retinal degeneration. Here we report that ADIPOR1 protein is primarily found in the eye and brain with little expression in other tissues. Further analysis of AdipoR1 KO mice revealed that these animals exhibit early visual system abnormalities and are depleted of RHODOPSIN prior to pronounced photoreceptor death. A KO of AdipoR1 post-development either in photoreceptors or the retinal pigment epithelium (RPE) resulted in decreased expression of retinal proteins, establishing a role for ADIPOR1 in supporting vision in adulthood. Subsequent analysis of the Mfr
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