409 research outputs found
Adolescents’ use of purpose built shade in secondary schools: cluster randomised controlled trial
Objective To examine whether students use or avoid newly shaded areas created by shade sails installed at schools
Association of Progressive CD4+ T Cell Decline in SIV Infection with the Induction of Autoreactive Antibodies
The progressive decline of CD4+ T cells is a hallmark of disease progression in human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infection. Whereas the acute phase of the infection is dominated by virus-mediated depletion of memory CD4+ T cells, chronic infection is often associated with a progressive decline of total CD4+ T cells, including the naïve subset. The mechanism of this second phase of CD4+ T cell loss is unclear and may include immune activation–induced cell death, immune-mediated destruction, and regenerative or homeostatic failure. We studied patterns of CD4+ T cell subset depletion in blood and tissues in a group of 20 rhesus macaques inoculated with derivatives of the pathogenic SIVsmE543-3 or SIVmac239. Phenotypic analysis of CD4+ T cells demonstrated two patterns of CD4+ T cell depletion, primarily affecting either naïve or memory CD4+ T cells. Progressive decline of total CD4+ T cells was observed only in macaques with naïve CD4+ T cell depletion (ND), though the depletion of memory CD4+ T cells was profound in macaques with memory CD4+ T cell depletion (MD). ND macaques exhibited lower viral load and higher SIV-specific antibody responses and greater B cell activation than MD macaques. Depletion of naïve CD4+ T cells was associated with plasma antibodies autoreactive with CD4+ T cells, increasing numbers of IgG-coated CD4+ T cells, and increased incidence of autoreactive antibodies to platelets (GPIIIa), dsDNA, and phospholipid (aPL). Consistent with a biological role of these antibodies, these latter antibodies were accompanied by clinical features associated with autoimmune disorders, thrombocytopenia, and catastrophic thrombotic events. More importantly for AIDS pathogenesis, the level of autoreactive antibodies significantly correlated with the extent of naïve CD4+ T cell depletion. These results suggest an important role of autoreactive antibodies in the CD4+ T cell decline observed during progression to AIDS
Demonstrating high-precision photometry with a CubeSat: ASTERIA observations of 55 Cancri e
ASTERIA (Arcsecond Space Telescope Enabling Research In Astrophysics) is a 6U
CubeSat space telescope (10 cm x 20 cm x 30 cm, 10 kg). ASTERIA's primary
mission objective was demonstrating two key technologies for reducing
systematic noise in photometric observations: high-precision pointing control
and high-stabilty thermal control. ASTERIA demonstrated 0.5 arcsecond RMS
pointing stability and 10 milliKelvin thermal control of its camera
payload during its primary mission, a significant improvement in pointing and
thermal performance compared to other spacecraft in ASTERIA's size and mass
class. ASTERIA launched in August 2017 and deployed from the International
Space Station (ISS) November 2017. During the prime mission (November 2017 --
February 2018) and the first extended mission that followed (March 2018 - May
2018), ASTERIA conducted opportunistic science observations which included
collection of photometric data on 55 Cancri, a nearby exoplanetary system with
a super-Earth transiting planet. The 55 Cancri data were reduced using a custom
pipeline to correct CMOS detector column-dependent gain variations. A Markov
Chain Monte Carlo (MCMC) approach was used to simultaneously detrend the
photometry using a simple baseline model and fit a transit model. ASTERIA made
a marginal detection of the known transiting exoplanet 55 Cancri e
(~\Rearth), measuring a transit depth of ppm. This is the
first detection of an exoplanet transit by a CubeSat. The successful detection
of super-Earth 55 Cancri e demonstrates that small, inexpensive spacecraft can
deliver high-precision photometric measurements.Comment: 23 pages, 9 figures. Accepted in A
Measuring how communication and engagement efforts help deliver outcomes
Key messages
Initial steps towards outcome-focused monitoring, evaluation & learning (MEL) on communication and engagement can be small, but they must be systematic.
To achieve broad participation, MEL needs to be lean and do-able.
Well-designed MEL adds value by feeding information and lessons into future work and decision-making.
Adequate time must be devoted to embedding MEL into the initial activity plan and following it throughout the communication engagement activity and afterwards.
MEL is easier when it is done more often. It is helpful to draw upon resource persons.
Preparatory work and capturing feedback through mechanisms built into the communication- engagement activity is more informative than soliciting responses afterwards.
Peer exchanges about MEL practices and adaptable templates are beneficial.
Aligning specific communication activities with the established impact pathway can ensure more strategic and focused activities and products that contribute to outcomes and impact
OPA1 deficiency associated with increased autophagy in retinal ganglion cells in a murine model of dominant optic atrophy
purpose. To examine retinal ganglion cell (RGC) and axonal abnormalities in an ENU-induced mutant mouse carrying a protein-truncating nonsense mutation in OPA1. Mutations in the OPA1 gene cause autosomal dominant optic atrophy (ADOA) in which loss of RGCs followed by myelin degeneration in the optic nerve leads to progressive decrease in visual acuity.
methods. Ultrastructure of the optic nerve was examined in heterozygous mutants and wild-type littermate controls at 6, 9, and 24 months using electron microscopy. The RGC layer was examined at 6 and 24 months.
results. There was an increase in the number of autophagosomes in the RGC layer in heterozygous mutants compared with wild type at 24 months. Signs of optic nerve degeneration were seen as early as 9 months in Opa1+/− mice, with more severe degeneration by 24 months. By 24 months, degeneration of axons was also seen in control mice. Numbers of opaque mitochondria in the Opa1+/− mice increased at 6 and 24 months, possibly representing an increase in the density of cristae to fulfill the energy requirements of the axon. In addition, mitochondria with vesiculation of the inner membranes, similar to the mutant mitochondria described in a mouse model of Charcot-Marie-Tooth type 2A, were observed.
conclusions. Mutations in OPA1 cause pathologic changes to optic nerve axons that are similar to, but occur earlier than, age-related degeneration. Increased autophagy is likely to result from an increase in abnormal mitochondria and could be one mechanism contributing to RGC loss and subsequent optic atrophy seen in ADOA
Exercise and manual physiotherapy arthritis research trial (EMPART) for osteoarthritis of the hip: a multicenter randomized controlled trial.
OBJECTIVES: To determine the effectiveness of exercise therapy (ET) compared with ET with adjunctive manual therapy (MT) for people with hip osteoarthritis (OA); and to identify if immediate commencement of treatment (ET or ET+MT) was more beneficial than a 9-week waiting period for either intervention.
DESIGN: Assessor-blind randomized controlled trial with a 9-week and 18-week follow-up.
SETTING: Four academic teaching hospitals in Dublin, Ireland.
PARTICIPANTS: Patients (N=131) with hip OA recruited from general practitioners, rheumatologists, orthopedic surgeons, and other hospital consultants were randomized to 1 of 3 groups: ET (n=45), ET+MT (n=43), and waitlist controls (n=43).
INTERVENTIONS: Participants in both the ET and ET+MT groups received up to 8 treatments over 8 weeks. Control group participants were rerandomized into either ET or ET+MT groups after 9 week follow-up. Their data were pooled with original treatment group data: ET (n=66) and ET+MT (n=65).
MAIN OUTCOME MEASURES: The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function (PF) subscale. Secondary outcomes included physical performance, pain severity, hip range of motion (ROM), anxiety/depression, quality of life, medication usage, patient-perceived change, and patient satisfaction.
RESULTS: There was no significant difference in WOMAC PF between the ET (n=66) and ET+MT (n=65) groups at 9 weeks (mean difference, .09; 95% confidence interval [CI] -2.93 to 3.11) or 18 weeks (mean difference, .42; 95% CI, -4.41 to 5.25), or between other outcomes, except patient satisfaction with outcomes, which was higher in the ET+MT group (P=.02). Improvements in WOMAC, hip ROM, and patient-perceived change occurred in both treatment groups compared with the control group.
CONCLUSIONS: Self-reported function, hip ROM, and patient-perceived improvement occurred after an 8-week program of ET for patients with OA of the hip. MT as an adjunct to exercise provided no further benefit, except for higher patient satisfaction with outcome
Sewage-associated plastic waste washed up on beaches can act as a reservoir for faecal bacteria, potential human pathogens, and genes for antimicrobial resistance
Sewage-associated plastic wastes, such as wet wipes and cotton bud sticks, commonly wash up on beaches; however, it is unclear whether this represents a public health risk. In this study, sewage-associated plastic waste, and naturally occurring substrates (seaweed and sand), were collected from ten beaches along the Firth of Forth estuary (Scotland, UK) and analysed using selective media for the faecal indicator organisms (FIOs) E. coli and intestinal enterococci (IE), and potential human pathogens (Vibrio spp.). Minimum inhibitory concentration (MIC) analysis was used to determine antibiotic resistance in selected strains. FIOs and Vibrio were more often associated with wet wipes and cotton bud sticks than with seaweed, and there was evidence of resistance to several antibiotics. This work demonstrates that plastics associated with sewage pollution can facilitate the survival and dissemination of FIOs and Vibrio and thus, could present an as yet unquantified potential risk to human health at the beach
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A point mutation decouples the lipid transfer activities of microsomal triglyceride transfer protein.
Funder: G. Harold and Leila Y. Mathers Charitable Foundation; funder-id: http://dx.doi.org/10.13039/100001229Apolipoprotein B-containing lipoproteins (B-lps) are essential for the transport of hydrophobic dietary and endogenous lipids through the circulation in vertebrates. Zebrafish embryos produce large numbers of B-lps in the yolk syncytial layer (YSL) to move lipids from yolk to growing tissues. Disruptions in B-lp production perturb yolk morphology, readily allowing for visual identification of mutants with altered B-lp metabolism. Here we report the discovery of a missense mutation in microsomal triglyceride transfer protein (Mtp), a protein that is essential for B-lp production. This mutation of a conserved glycine residue to valine (zebrafish G863V, human G865V) reduces B-lp production and results in yolk opacity due to aberrant accumulation of cytoplasmic lipid droplets in the YSL. However, this phenotype is milder than that of the previously reported L475P stalactite (stl) mutation. MTP transfers lipids, including triglycerides and phospholipids, to apolipoprotein B in the ER for B-lp assembly. In vitro lipid transfer assays reveal that while both MTP mutations eliminate triglyceride transfer activity, the G863V mutant protein unexpectedly retains ~80% of phospholipid transfer activity. This residual phospholipid transfer activity of the G863V mttp mutant protein is sufficient to support the secretion of small B-lps, which prevents intestinal fat malabsorption and growth defects observed in the mttpstl/stl mutant zebrafish. Modeling based on the recent crystal structure of the heterodimeric human MTP complex suggests the G865V mutation may block triglyceride entry into the lipid-binding cavity. Together, these data argue that selective inhibition of MTP triglyceride transfer activity may be a feasible therapeutic approach to treat dyslipidemia and provide structural insight for drug design. These data also highlight the power of yolk transport studies to identify proteins critical for B-lp biology
Astronomy’s climate emissions: Global travel to scientific meetings in 2019
Travel to academic conferences—where international flights are the norm—is responsible for a sizeable fraction of the greenhouse gas (GHG) emissions associated with academic work. In order to provide a benchmark for comparison with other fields, as well as for future reduction strategies and assessments, we estimate the CO2-equivalent emissions for conference travel in the field of astronomy for the prepandemic year 2019. The GHG emission of the international astronomical community’s 362 conferences and schools in 2019 amounted to 42,500 tCO2e, assuming a radiative-forcing index factor of 1.95 for air travel. This equates to an average of 1.0 ± 0.6 tCO2e per participant per meeting. The total travel distance adds up to roughly 1.5 Astronomical Units, that is, 1.5 times the distance between the Earth and the Sun. We present scenarios for the reduction of this value, for instance with virtual conferencing or hub models, while still prioritizing the benefits conferences bring to the scientific community
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