75 research outputs found
CD32 is expressed on cells with transcriptionally active HIV but does not enrich for HIV DNA in resting T cells
The persistence of HIV reservoirs, including latently infected, resting CD4+ T cells, is the major obstacle to cure HIV infection. CD32a expression was recently reported to mark CD4+ T cells harboring a replication-competent HIV reservoir during antiretroviral therapy (ART) suppression. We aimed to determine whether CD32 expression marks HIV latently or transcriptionally active infected CD4+ T cells. Using peripheral blood and lymphoid tissue of ART-treated HIV+ or SIV+ subjects, we found that most of the circulating memory CD32+ CD4+ T cells expressed markers of activation, including CD69, HLA-DR, CD25, CD38, and Ki67, and bore a TH2 phenotype as defined by CXCR3, CCR4, and CCR6. CD32 expression did not selectively enrich for HIV- or SIV-infected CD4+ T cells in peripheral blood or lymphoid tissue; isolated CD32+ resting CD4+ T cells accounted for less than 3% of the total HIV DNA in CD4+ T cells. Cell-associated HIV DNA and RNA loads in CD4+ T cells positively correlated with the frequency of CD32+ CD69+ CD4+ T cells but not with CD32 expression on resting CD4+ T cells. Using RNA fluorescence in situ hybridization, CD32 coexpression with HIV RNA or p24 was detected after in vitro HIV infection (peripheral blood mononuclear cell and tissue) and in vivo within lymph node tissue from HIV-infected individuals. Together, these results indicate that CD32 is not a marker of resting CD4+ T cells or of enriched HIV DNA–positive cells after ART; rather, CD32 is predominately expressed on a subset of activated CD4+ T cells enriched for transcriptionally active HIV after long-term ART
The QUIJOTE experiment: project status and first scientific results
We present the current status of the QUIJOTE (Q-U-I JOint TEnerife) experiment, a new polarimeter with the aim of characterizing the polarization of the Cosmic Microwave Background, and other galactic or extra-galactic physical processes that emit in microwaves in the frequency range 10–42 GHz, and at large angular scales (around 1 degree resolution). The experiment has been designed to reach the required sensitivity to detect a primordial gravitational wave component in the CMB, provided its tensor-to-scalar ratio is larger than r ∼ 0.05. The project consists of two telescopes and three instruments which will survey a large sky area from the Teide Observatory to provide I, Q and U maps of high sensitivity. The first QUIJOTE instrument, known as Multi-Frequency Instrument (MFI), has been surveying the northern sky in four individual frequencies between 10 and 20 GHz since November 2012, providing data with an average sensitivity of 80 µK beam−1 in Q and U in a region of 20, 000 square-degrees. The second instrument, or Thirty-GHz Instrument (TGI), is currently undergoing the commissioning phase, and the third instrument, or Forty-GHz Instrument (FGI), is in the final fabrication phase. Finally, we describe the first scientific results obtained with the MFI. Some specific regions, mainly along the Galactic plane, have been surveyed to a deeper depth, reaching sensitivities of around 40 µK beam−1. We present new upper limits on the polarization of the anomalous dust emission, resulting from these data, in the Perseus molecular complex and in the W43 molecular complex
Carbon uptake by mature Amazon forests has mitigated Amazon nations' carbon emissions
BACKGROUND: Several independent lines of evidence suggest that Amazon forests have provided a significant carbon sink service, and also that the Amazon carbon sink in intact, mature forests may now be threatened as a result of different processes. There has however been no work done to quantify non-land-use-change forest carbon fluxes on a national basis within Amazonia, or to place these national fluxes and their possible changes in the context of the major anthropogenic carbon fluxes in the region. Here we present a first attempt to interpret results from ground-based monitoring of mature forest carbon fluxes in a biogeographically, politically, and temporally differentiated way. Specifically, using results from a large long-term network of forest plots, we estimate the Amazon biomass carbon balance over the last three decades for the different regions and nine nations of Amazonia, and evaluate the magnitude and trajectory of these differentiated balances in relation to major national anthropogenic carbon emissions. RESULTS: The sink of carbon into mature forests has been remarkably geographically ubiquitous across Amazonia, being substantial and persistent in each of the five biogeographic regions within Amazonia. Between 1980 and 2010, it has more than mitigated the fossil fuel emissions of every single national economy, except that of Venezuela. For most nations (Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname) the sink has probably additionally mitigated all anthropogenic carbon emissions due to Amazon deforestation and other land use change. While the sink has weakened in some regions since 2000, our analysis suggests that Amazon nations which are able to conserve large areas of natural and semi-natural landscape still contribute globally-significant carbon sequestration. CONCLUSIONS: Mature forests across all of Amazonia have contributed significantly to mitigating climate change for decades. Yet Amazon nations have not directly benefited from providing this global scale ecosystem service. We suggest that better monitoring and reporting of the carbon fluxes within mature forests, and understanding the drivers of changes in their balance, must become national, as well as international, priorities
Carbon uptake by mature Amazon forests has mitigated Amazon nations' carbon emissions
Background: Several independent lines of evidence suggest that Amazon forests have provided a significant carbon
sink service, and also that the Amazon carbon sink in intact, mature forests may now be threatened as a result of
different processes. There has however been no work done to quantify non-land-use-change forest carbon fluxes on
a national basis within Amazonia, or to place these national fluxes and their possible changes in the context of the
major anthropogenic carbon fluxes in the region. Here we present a first attempt to interpret results from groundbased
monitoring of mature forest carbon fluxes in a biogeographically, politically, and temporally differentiated way.
Specifically, using results from a large long-term network of forest plots, we estimate the Amazon biomass carbon balance
over the last three decades for the different regions and nine nations of Amazonia, and evaluate the magnitude
and trajectory of these differentiated balances in relation to major national anthropogenic carbon emissions.
Results: The sink of carbon into mature forests has been remarkably geographically ubiquitous across Amazonia,
being substantial and persistent in each of the five biogeographic regions within Amazonia. Between 1980 and 2010,
it has more than mitigated the fossil fuel emissions of every single national economy, except that of Venezuela. For
most nations (Bolivia, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname) the sink has probably additionally
mitigated all anthropogenic carbon emissions due to Amazon deforestation and other land use change. While the
sink has weakened in some regions since 2000, our analysis suggests that Amazon nations which are able to conserve
large areas of natural and semi-natural landscape still contribute globally-significant carbon sequestration.
Conclusions: Mature forests across all of Amazonia have contributed significantly to mitigating climate change for
decades. Yet Amazon nations have not directly benefited from providing this global scale ecosystem service. We suggest
that better monitoring and reporting of the carbon fluxes within mature forests, and understanding the drivers
of changes in their balance, must become national, as well as international, priorities
Long-term decline of the Amazon carbon sink
Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades1, 2, with a substantial fraction of this sink probably located in the tropics3, particularly in the Amazon4. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity5. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale1, 2, and is contrary to expectations based on models6
Multicenter study of plastic vs. self-expanding metal stents in endoscopic ultrasound-guided drainage of walled-off pancreatic necrosis - PROMETHEUS: a randomized controlled trial protocol.
Background: It seems that lumen-apposing metal stents (LAMS) are displacing plastic stents in the therapy of pancreatic-fluid collection in walled-off necrosis (WON). To date, there is no quality of evidence to recommend LAMS as the standard treatment in the management of WON. The theoretical benefit of LAMS over plastic stents needs to be proven. Methods/design: This is a randomized controlled, multicenter, prospective clinical trial with two parallel groups, without masking. One-hundred and fourteen patients with WON will undergo endoscopic ultrasound (EUS)-guided transmural draining in nine tertiary hospitals in Spain and will be randomized to the LAMS or plastic-stent group. The primary endpoint is the short-term (4 weeks) clinical success determined by the reduction of the collection (to < 50% or < 5 cm in size), along with clinical improvement. Secondary endpoints: long-term (4 months) clinical success (total resolution or 5 cm), procedure duration, level of difficulty, safety, and recurrences. Discussion: The PROMETHEUS trial has been designed to determine whether LAMS are superior to plastic stents in EUS-guided transmural drainage of WON
Non-invasive ventilation in obesity hypoventilation syndrome without severe obstructive sleep apnoea
Background Non-invasive ventilation (NIV) is an effective form of treatment in patients with obesity hypoventilation syndrome (OHS) who have concomitant severe obstructive sleep apnoea (OSA). However, there is a paucity of evidence on the efficacy of NIV in patients with OHS without severe OSA. We performed a multicentre randomised clinical trial to determine the comparative efficacy of NIV versus lifestyle modification (control group) using daytime arterial carbon dioxide tension (PaCO2) as the main outcome measure. Methods Between May 2009 and December 2014 we sequentially screened patients with OHS without severe OSA. Participants were randomised to NIV versus lifestyle modification and were followed for 2 months. Arterial blood gas parameters, clinical symptoms, health-related quality of life assessments, polysomnography, spirometry, 6-min walk distance test, blood pressure measurements and healthcare resource utilisation were evaluated. Statistical analysis was performed using intention-to-treat analysis. Results A total of 365 patients were screened of whom 58 were excluded. Severe OSA was present in 221 and the remaining 86 patients without severe OSA were randomised. NIV led to a significantly larger improvement in PaCO2 of -6 (95% CI -7.7 to -4.2) mm Hg versus -2.8 (95% CI -4.3 to -1.3) mm Hg, (p<0.001) and serum bicarbonate of -3.4 (95% CI -4.5 to -2.3) versus -1 (95% CI -1.7 to -0.2 95% CI) mmol/L (p<0.001). PaCO2 change adjusted for NIV compliance did not further improve the inter-group statistical significance. Sleepiness, some health-related quality of life assessments and polysomnographic parameters improved significantly more with NIV than with lifestyle modification. Additionally, there was a tendency towards lower healthcare resource utilisation in the NIV group. Conclusions NIV is more effective than lifestyle modification in improving daytime PaCO2, sleepiness and polysomnographic parameters. Long-term prospective studies are necessary to determine whether NIV reduces healthcare resource utilisation, cardiovascular events and mortality
Power training and postmenopausal hormone therapy affect transcriptional control of specific co-regulated gene clusters in skeletal muscle
At the moment, there is no clear molecular explanation for the steeper decline in muscle performance after menopause or the mechanisms of counteractive treatments. The goal of this genome-wide study was to identify the genes and gene clusters through which power training (PT) comprising jumping activities or estrogen containing hormone replacement therapy (HRT) may affect skeletal muscle properties after menopause. We used musculus vastus lateralis samples from early stage postmenopausal (50–57 years old) women participating in a yearlong randomized double-blind placebo-controlled trial with PT and HRT interventions. Using microarray platform with over 24,000 probes, we identified 665 differentially expressed genes. The hierarchical clustering method was used to assort the genes. Additionally, enrichment analysis of gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways was carried out to clarify whether assorted gene clusters are enriched with particular functional categories. The analysis revealed transcriptional regulation of 49 GO/KEGG categories. PT upregulated transcription in “response to contraction”—category revealing novel candidate genes for contraction-related regulation of muscle function while HRT upregulated gene expression related to functionality of mitochondria. Moreover, several functional categories tightly related to muscle energy metabolism, development, and function were affected regardless of the treatment. Our results emphasize that during the early stages of the postmenopause, muscle properties are under transcriptional modulation, which both PT and HRT partially counteract leading to preservation of muscle power and potentially reducing the risk for aging-related muscle weakness. More specifically, PT and HRT may function through improving energy metabolism, response to contraction as well as by preserving functionality of the mitochondria
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Global cardiac anesthesia workforce assessment – a cross-sectional observational survey study.
ObjectiveThe primary aim of this survey was to assess the demographics, training background, practice setting, and work environment of cardiac anesthesiologists globally.DesignCross-sectional study of the global cardiac anesthesia workforce. A multilingual web-based survey was conducted between June 1 and December 31, 2023.SettingThe survey was distributed via cardiac anesthesia societies, special interest groups, and social media using a non-probabilistic sample and with snowballing techniques.ParticipantsAnesthesiologists actively practicing cardiac anesthesia.InterventionsNone.Measurements and main resultsIn total, 3,430 participants from 99 countries responded. Results were summarized as descriptive data comparing geographical regions, and noticeable differences for individual countries were assessed. Most of the workforce (85.9%, n = 2,913/3,390) that responded to the survey were between 31 and 60 years of age. Australia/New Zealand/Oceania (51.1%, n = 48/94) and Asia (45.2%, n = 606/1,341) had the largest percentages of respondents working in the above 50 years of age group. Globally, 48.4% (n = 1,347/2,780) of respondents reported having completed an accredited adult cardiac fellowship, and 42.7% (n = 918/2,148) replied to have had only informal training "on the job." When it comes to transesophageal echocardiography, 44.6% (n = 1,240/2,780) of the global workforce reports not having had any formal training. Large differences in training background were noticed by country and region. Most of the workforce (43.3%, n = 1,149/2,652) indicated working between 41 and 60 hours per week. However, more than one of four (26.8%, n = 711/2,652) cardiac anesthesiologists work between 61 to 80 hours, and one out of ten (10.5%, n = 279/2,652) has a workload of more than 81 hours per week. A majority (68%, n = 1,778/2,609) of cardiac anesthesiologists evaluated their compensation/salary as less than adequate or just adequate but not enough to save for retirement. Regarding work-life balance, there was a significant variation in how practitioners assessed their personal situations. Almost half (46.3%, n = 1,185/2,560) of the workforce consider making changes to reduce their workload, and only 23.1% (n = 592/2,560) evaluated their work-life balance as just right. A validated, non-proprietary single-question item assessing emotional exhaustion as one of the three established criteria for burnout was incorporated into the survey. The overall prevalence of burnout, i.e. emotional exhaustion, among cardiac anesthesiologists was 31.7% (n = 827/2,609). In the regression analysis, an increase in clinical work hours (OR = 1.28; CI [1.16, 1.42]; p < 0.001), the number (OR = 1.05; CI [1.02, 1.08]; p < 0.001) and type (OR =1.09; CI [1.0, 1.19]; p = 0.03) of cardiac call, all increased the odds for burnout. Compared to taking all cardiac call in the hospital, taking no cardiac call at all, significantly decreased the risk for burnout. Similarly, compared to compensation that was perceived as less than adequate, i.e., even needing a second income, higher compensation assessment was associated with an increasingly lower risk for burnout. Other factors mitigating burnout risk include older age groups (OR = 0.78; CI [0.67, 0.90]; p < 0.001), and a more positive outlook on work-life balance (OR = 0.88; CI [0.85, 0.92]; p < 0.001). The geographical region had a small but significant association with burnout (OR 1.12; CI [1.06, 1.18]; p < 0.001). Asia, as the geographical region of practice, had the highest odds for burnout overall (41.3%, n = 342/829) and also the most respondents (15.6%, n = 129/829) in the highest answer option category, i.e., feeling completely burned out.ConclusionsA global survey of the cardiac anesthesia workforce found inconsistency in the training, job satisfaction, and daily practice of cardiac anesthesiologists. The rate of burnout was high, and many respondents would like to make work-related changes to improve work-life balance
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