The human betaherpesviruses including human cytomegalovirus (HCMV), human herpesvirus (HHV)-6a and HHV-6b, and HHV-7 infect and establish latency in CD34+ hematopoietic stem and progenitor cells ...(HPCs). The diverse repertoire of HPCs in humans and the complex interactions between these viruses and host HPCs regulate the viral lifecycle, including latency. Precise manipulation of host and viral factors contribute to preferential maintenance of the viral genome, increased host cell survival, and specific manipulation of the cellular environment including suppression of neighboring cells and immune control. The dynamic control of these processes by the virus regulate inter- and intra-host signals critical to the establishment of chronic infection. Regulation occurs through direct viral protein interactions and cellular signaling, miRNA regulation, and viral mimics of cellular receptors and ligands, all leading to control of cell proliferation, survival, and differentiation. Hematopoietic stem cells have unique biological properties and the tandem control of virus and host make this a unique environment for chronic herpesvirus infection in the bone marrow. This review highlights the elegant complexities of the betaherpesvirus latency and HPC virus-host interactions.
Abstract Food insecurity acts as a chronic stressor independent of poverty. Food-insecure adults may consume more highly palatable foods as a coping mechanism, leading to poorer diet quality and ...increased risks of chronic disease over time. Using data from the 1999-2008 National Health and Nutrition Examination Surveys, this study aimed to examine the cross-sectional differences in dietary intake and diet quality by household food security among 8,129 lower-income adults (≤300% of the federal poverty level). Food insecurity was assessed using the 18-item US Household Food Security Survey Module. Dietary intake was assessed from 24-hour recalls and diet quality was measured using the Healthy Eating Index-2005 and the Alternate Healthy Eating Index-2010. Relative mean differences in dietary outcomes by household food security were estimated using linear regression models, adjusting for sociodemographic characteristics. Lower-income food-insecure adults reported higher consumption of some highly palatable foods, including high-fat dairy products ( P trend<0.0001) and salty snacks ( P trend=0.01) compared with lower-income food-secure adults. Food insecurity was also associated with more sugar-sweetened beverages ( P trend=0.003); more red/processed meat ( P trend=0.005); more nuts, seeds, and legumes ( P trend=0.0006); fewer vegetables ( P trend<0.0001); and fewer sweets and bakery desserts ( P trend=0.0002). No differences were observed for intakes of total energy and macronutrients. Food insecurity was significantly associated with lower Healthy Eating Index-2005 ( P trend<0.0001) and Alternate Healthy Eating Index-2010 scores ( P trend<0.0001). Despite no macronutrient differences, food insecurity was associated with characteristics of poor diet quality known to increase chronic disease risk.
Background
Opioids are a common and essential treatment for acute sickle cell disease (SCD) pain. However, opioids carry well‐known adverse side effects, including potential development of ...hyperalgesia and nociplastic pain. We characterized opioid use in youth with SCD using ecological momentary assessment (EMA) data, and investigated the relationships between home‐based opioid use, pain, and a range of biopsychosocial factors.
Method
Eighty‐eight youth with SCD (aged 8–17 years) completed EMAs assessing home‐based opioid use, pain, and related factors. Analyses consisted of descriptive and multilevel logistic regression to predict daily home opioid use.
Results
Youth averaged 3.64 weeks of EMAs. Approximately 35% of the sample (n = 31) took an opioid during the EMA period, and used them on only 24% of reported pain days. Youth who took opioids reported a higher percentage of pain days (t = −2.67, p < .05) and mean pain severity scores (t = −2.30, p < .05) than youth who did not take opioids. Multilevel logistic regression analyses indicated that high daily pain severity (odds ratio OR = 1.02, p < .01), older age (OR = 1.324, p < .01), and low positive affect (OR = 0.91, p < .01) were each related to an increased likelihood of opioid use.
Conclusion
Youth with SCD take opioids appropriately in response to their pain, based on daily self‐report. Beyond daily pain severity, age, and daily variation in positive affect were related to home‐based opioid use. This suggests that behavioral interventions that enhance positive affect may promote reduced opioid use among youth with SCD.
Genome duplications and ploidy transitions have occurred in nearly every major taxon of eukaryotes, but they are far more common in plants than in animals. Due to the conservation of the ...nuclear:cytoplasmic volume ratio increased DNA content results in larger cells. In plants, polyploid organisms are larger than diploids as cell number remains relatively constant. Conversely, vertebrate body size does not correlate with cell size and ploidy as vertebrates compensate for increased cell size to maintain tissue architecture and body size. This has historically been explained by a simple reduction in cell number that matches the increase in cell size maintaining body size as ploidy increases, but here we show that the compensatory mechanisms that maintain body size in triploid zebrafish are tissue-specific: A) erythrocytes respond in the classical pattern with a reduced number of larger erythrocytes in circulation, B) muscle, a tissue comprised of polynucleated muscle fibers, compensates by reducing the number of larger nuclei such that myofiber and myotome size in unaffected by ploidy, and C) vascular tissue compensates by thickening blood vessel walls, possibly at the expense of luminal diameter. Understanding the physiological implications of ploidy on tissue function requires a detailed description of the specific mechanisms of morphological compensation occurring in each tissue to understand how ploidy changes affect development and physiology.
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•Tissue-specific mechanisms compensate for changes in cell size.•Blastomere size, cleavage pattern and rate are not affected by ploidy.•Erythrocytes conform to the canonical pattern of ‘fewer but larger cells'.•Multinucleate skeletal muscle cells adjust the number of nuclei to maintain size.•Vasculature is comprised of the same number and pattern of larger endothelial cells.
Reactivation of latent Human Cytomegalovirus (HCMV) in CD34+ hematopoietic progenitor cells (HPCs) is closely linked to hematopoiesis. Viral latency requires maintenance of the progenitor cell ...quiescence, while reactivation initiates following mobilization of HPCs to the periphery and differentiation into CD14+ macrophages. Early growth response gene 1 (EGR-1) is a transcription factor activated by Epidermal growth factor receptor (EGFR) signaling that is essential for the maintenance of CD34+ HPC self-renewal in the bone marrow niche. Down-regulation of EGR-1 results in mobilization and differentiation of CD34+ HPC from the bone marrow to the periphery. In the current study we demonstrate that the transcription factor EGR-1 is directly targeted for down-regulation by HCMV miR-US22 that results in decreased proliferation of CD34+ HPCs and a decrease in total hematopoietic colony formation. We also show that an HCMV miR-US22 mutant fails to reactivate in CD34+ HPCs, indicating that expression of EGR-1 inhibits viral reactivation. Since EGR-1 promotes CD34+ HPC self-renewal in the bone marrow niche, HCMV miR-US22 down-regulation of EGR-1 is a necessary step to block HPC self-renewal and proliferation to induce a cellular differentiation pathway necessary to promote reactivation of virus.
Interpretation of tower-based eddy covariance (EC) carbon dioxide flux (
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) measurements in urban areas is challenging because of the location bias of EC instruments. This bias results from EC ...point measurements taken above a complex CO
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source/sink surface that is spatially heterogeneous at scales approaching or exceeding those of the turbulent flux source areas. This makes it difficult to accomplish traditional measurement objectives such as calculating spatially unbiased ecosystem-wide cumulative
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totals or objectively comparing
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during different environmental conditions (e.g., day vs. night or seasonal differences). This study uses a multiyear
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dataset measured over a residential area of Vancouver, BC, Canada from a 30-m flux tower in close proximity to a busy traffic intersection on one side. The
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measurements are analyzed using surface geospatial data and turbulent flux source area models to exploit location bias to develop methods to statistically model individual emissions and uptake processes in terms of environmental controls and surface land cover. The empirical relations between controls and measured
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are used to spatially and temporally downscale individual CO
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emissions/uptake processes that are then used to create high-resolution maps (20 m) and calculate ecosystem-wide
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at temporal resolutions of 30 min to 1 year. At this site, the modeled ecosystem-wide annual net
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total is calculated as 6.42 kg C m
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year
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with traffic emissions estimated to account for 68.8 % of the total net emissions. Building sources contribute 27.9 %, respiration from soil and vegetation is 5.5 %, respiration from humans 5.0 %, and photosynthesis offsets are −7.2 % of the annual net total. The statistical models developed here are then tested by direct comparison to independent EC measurements using land cover scalings derived from 30-min source area models. Results are also scaled to ecosystem-averaged land cover to compare results to independent emissions/uptake models.
The strength and permeability of fault zones must be quantified in order to accurately predict crustal strength and subsurface fluid migration. To this end, we performed experiments on mixtures of ...fine‐grained quartz and kaolinite incremented at 10 wt% intervals between the two end‐member components (analogues for natural fault gouge) in order to establish their strength and fluid flow properties during hydrostatic and shear loading. Hydrostatically compacted samples exhibited permeability reduction on increasing effective pressures from 5 MPa to 50 MPa, with the rate of reduction displaying strong dependency on the synthetic fault gouge composition. The permeability decreases continuously with increasing kaolinite content. Porosity exhibits a distinct minimum that evolves with increasing effective pressure according to the relative compaction of the quartz and kaolinite end‐members. Porosity evolution with increasing clay content is predicted satisfactorily by a simple ideal packing model. At the highest effective pressure (50 MPa), permeability reduced log‐linearly over 4 orders of magnitude with increasing clay content. Mechanically, sheared gouge samples showed a continuous reduction in frictional strength with increasing clay fraction. Permeability decreased further on shear loading after initial hydrostatic compaction to 50 MPa. This was most evident for the pure quartz end‐member, with two orders of magnitude additional reduction, whereas the clay‐rich samples were reduced only tenfold, mostly before a shear strain of 5. Variation of permeability with both clay content and shear deformation may be adequately described by previously published empirical predictors for fault zone permeability. Clay content has the largest effect on permeability, and shear deformation affects permeability of quartz‐rich gouges more than clay‐rich gouges.
This contribution reports CO2 mixing ratios measured in the urban canopy layer (UCL) of a residential neighborhood in Vancouver, BC, Canada and discusses the relevance of UCL CO2 temporal and spatial ...variability to local-scale eddy covariance (EC) fluxes measured above the UCL. Measurements were conducted from a mobile vehicle-mounted platform over a continuous, 26-h period in the longterm turbulent flux source area of an urban EC tower. Daytime mixing ratios were highest along arterial roads and largely a function of proximity to vehicle traffic CO2 sources. At night, there was a distinct negative correlation between potential air temperature and CO2 mixing ratios. The spatial distribution of CO2 was controlled by topography and micro-scale advective processes (i.e. cold-air pooling). Mobile CO2 measurements were then used to calculate CO2 storage changes (FS) in the UCL volume and compared to single-layer FS estimates calculated from the EC system. In total, five variations of FS were calculated. On average, the choice of FS calculation method affected net measured hourly emissions (FC) by 5.2%. Analysis of FS using a four-year dataset measured at the EC tower show FS was 2.8% of hourly FC for this site on average. At this urban EC location, FS was relatively minor compared to FC and calculation of FS using a single-layer method was adequate, though FS still represents a potentially large uncertainty during individual hours.
•The micro-scale variability of carbon dioxide was mapped in an urban environment.•During day, carbon dioxide was mainly a function of proximity to traffic.•At night, the distribution was controlled by accumulation due to cold-air pooling.•Hourly changes of carbon dioxide storage in the urban canopy layer were calculated.•Changes affected measured eddy covariance fluxes on average by 5%, but up to 123%.
Restrictions, social isolation, and uncertainty related to the global COVID-19 pandemic have disrupted the ways that parents and children maintain family routines, health, and wellbeing. Companion ...animals (pets) can be a critical source of comfort during traumatic experiences, although changes to family routines, such as those caused by COVID-19, can also bring about challenges like managing undesirable pet behaviours or pet-human interactions. We aimed to examine the relationship between pet attachment and mental health for both parents and their children during the COVID-19 pandemic in Australia. A total of 1,034 parents living with a child under 18 years and a cat or dog completed an online cross-sectional survey between July and October 2020. Path analysis using multivariate linear regression was conducted to examine associations between objective COVID-19 impacts, subjective worry about COVID-19, human-pet attachment, and mental health. After adjusting for core demographic factors, stronger pet-child attachment was associated with greater child anxiety (parent-reported, p < .001). Parent-pet attachment was not associated with self-reported psychological distress (p = .42), however, parents who reported a strong emotional closeness with their pet reported greater psychological distress (p = .002). Findings highlight the role of pets during times of change and uncertainty. It is possible that families are turning to animals as a source of comfort, during a time when traditional social supports are less accessible. Alternatively, strong pet attachment is likely to reflect high levels of empathy, which might increase vulnerability to psychological distress. Longitudinal evidence is required to delineate the mechanisms underpinning pet attachment and mental health.
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