2,713 research outputs found
High-resolution temporal profiling of transcripts during Arabidopsis leaf senescence reveals a distinct chronology of processes and regulation
Leaf senescence is an essential developmental process that impacts dramatically on crop yields and involves altered
regulation of thousands of genes and many metabolic and signaling pathways, resulting in major changes in the leaf. The
regulation of senescence is complex, and although senescence regulatory genes have been characterized, there is little
information on how these function in the global control of the process. We used microarray analysis to obtain a highresolution
time-course profile of gene expression during development of a single leaf over a 3-week period to senescence.
A complex experimental design approach and a combination of methods were used to extract high-quality replicated data
and to identify differentially expressed genes. The multiple time points enable the use of highly informative clustering to
reveal distinct time points at which signaling and metabolic pathways change. Analysis of motif enrichment, as well
as comparison of transcription factor (TF) families showing altered expression over the time course, identify clear groups
of TFs active at different stages of leaf development and senescence. These data enable connection of metabolic
processes, signaling pathways, and specific TF activity, which will underpin the development of network models to
elucidate the process of senescence
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Identification of extracellular glycerophosphodiesterases in Pseudomonas and their role in soil organic phosphorus remineralisation
In soils, phosphorus (P) exists in numerous organic and inorganic forms. However, plants can only acquire inorganic orthophosphate (Pi), meaning global crop production is frequently limited by P availability. To overcome this problem, rock phosphate fertilisers are heavily applied, often with negative environmental and socio-economic consequences. The organic P fraction of soil contains phospholipids that are rapidly degraded resulting in the release of bioavailable Pi. However, the mechanisms behind this process remain unknown. We identified and experimentally confirmed the function of two secreted glycerolphosphodiesterases, GlpQI and GlpQII, found in Pseudomonas stutzeri DSM4166 and Pseudomonas fluorescens SBW25, respectively. A series of co-cultivation experiments revealed that in these Pseudomonas strains, cleavage of glycerolphosphorylcholine and its breakdown product G3P occurs extracellularly allowing other bacteria to benefit from this metabolism. Analyses of metagenomic and metatranscriptomic datasets revealed that this trait is widespread among soil bacteria with Actinobacteria and Proteobacteria, specifically Betaproteobacteria and Gammaproteobacteria, the likely major players
Exploring early developmental changes in face scanning patterns during the perception of audiovisual mismatch of speech cues
Young infants are capable of integrating auditory and visual information and their speech perception can be influenced by visual cues, while 5-month-olds detect mismatch between mouth articulations and speech sounds. From 6 months of age, infants gradually shift their attention away from eyes and towards the mouth in articulating faces, potentially to benefit from intersensory redundancy of audiovisual (AV) cues. Using eye tracking, we investigated whether 6- to 9-month-olds showed a similar age-related increase of looking to the mouth, while observing congruent and/or redundant versus mismatched and non-redundant speech cues. Participants distinguished between congruent and incongruent AV cues as reflected by the amount of looking to the mouth. They showed an age-related increase in attention to the mouth, but only for non-redundant, mismatched AV speech cues. Our results highlight the role of intersensory redundancy and audiovisual mismatch mechanisms in facilitating the development of speech processing in infants under 12 months of age
A bacterial quorum-sensing precursor induces mortality in the marine coccolithophore, Emiliania huxleyi
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Frontiers in Microbiology 7 (2016): 59, doi:10.3389/fmicb.2016.00059.Interactions between phytoplankton and bacteria play a central role in mediating biogeochemical cycling and food web structure in the ocean. However, deciphering the chemical drivers of these interspecies interactions remains challenging. Here, we report the isolation of 2-heptyl-4-quinolone (HHQ), released by Pseudoalteromonas piscicida, a marine gamma-proteobacteria previously reported to induce phytoplankton mortality through a hitherto unknown algicidal mechanism. HHQ functions as both an antibiotic and a bacterial signaling molecule in cell–cell communication in clinical infection models. Co-culture of the bloom-forming coccolithophore, Emiliania huxleyi with both live P. piscicida and cell-free filtrates caused a significant decrease in algal growth. Investigations of the P. piscicida exometabolome revealed HHQ, at nanomolar concentrations, induced mortality in three strains of E. huxleyi. Mortality of E. huxleyi in response to HHQ occurred slowly, implying static growth rather than a singular loss event (e.g., rapid cell lysis). In contrast, the marine chlorophyte, Dunaliella tertiolecta and diatom, Phaeodactylum tricornutum were unaffected by HHQ exposures. These results suggest that HHQ mediates the type of inter-domain interactions that cause shifts in phytoplankton population dynamics. These chemically mediated interactions, and other like it, ultimately influence large-scale oceanographic processes.This research was support through funding from the Gordon and Betty Moore Foundation through Grant GBMF3301 to MJ and TM; NIH grant from the National Institute of Allergy and Infectious Disease (NIAID – 1R21Al119311-01) to TM and KW; the National Science Foundation (OCE – 1313747) and US National Institute of Environmental Health Science (P01-ES021921) through the Oceans and Human Health Program to BM. Additional financial support was provided to TM from the Flatley Discovery Lab
Pharmacists Are Not Mid-Level Providers
Pharmacists should not be classified as “mid-level” providers. This classification implies that there are different levels or a hierarchy of providers when in fact each health care provider brings unique and essential knowledge and contributions to the health care team and to the care of patients. Pharmacists are no exception. Timely issues germane to pharmacists, including dependent and independent practice, provider status, and professional identity, contribute to the rationale that pharmacists, just like all other health care providers, should be classified by their professional identity. While use of the term mid-level provider to identify various practitioners may not seem consequential, in today’s health care environment, words do matter when it comes to attributing value, and the contributions of all health care providers should be recognized as equally important to the patient care team
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Life-Expectancy Disparities Among Adults With HIV in the United States and Canada: The Impact of a Reduction in Drug- and Alcohol-Related Deaths Using the Lives Saved Simulation Model.
Improvements in life expectancy among people living with human immunodeficiency virus (PLWH) receiving antiretroviral treatment in the United States and Canada might differ among key populations. Given the difference in substance use among key populations and the current opioid epidemic, drug- and alcohol-related deaths might be contributing to the disparities in life expectancy. We sought to estimate life expectancy at age 20 years in key populations (and their comparison groups) in 3 time periods (2004-2007, 2008-2011, and 2012-2015) and the potential increase in expected life expectancy with a simulated 20% reduction in drug- and alcohol-related deaths using the novel Lives Saved Simulation model. Among 92,289 PLWH, life expectancy increased in all key populations and comparison groups from 2004-2007 to 2012-2015. Disparities in survival of approximately a decade persisted among black versus white men who have sex with men and people with (vs. without) a history of injection drug use. A 20% reduction in drug- and alcohol-related mortality would have the greatest life-expectancy benefit for black men who have sex with men, white women, and people with a history of injection drug use. Our findings suggest that preventing drug- and alcohol-related deaths among PLWH could narrow disparities in life expectancy among some key populations, but other causes of death must be addressed to further narrow the disparities
Trends and determinants of stillbirth in developing countries: results from the Global Network\u27s Population-Based Birth Registry.
BACKGROUND: Stillbirth rates remain high, especially in low and middle-income countries, where rates are 25 per 1000, ten-fold higher than in high-income countries. The United Nations\u27 Every Newborn Action Plan has set a goal of 12 stillbirths per 1000 births by 2030 for all countries.
METHODS: From a population-based pregnancy outcome registry, including data from 2010 to 2016 from two sites each in Africa (Zambia and Kenya) and India (Nagpur and Belagavi), as well as sites in Pakistan and Guatemala, we evaluated the stillbirth rates and rates of annual decline as well as risk factors for 427,111 births of which 12,181 were stillbirths.
RESULTS: The mean stillbirth rates for the sites were 21.3 per 1000 births for Africa, 25.3 per 1000 births for India, 56.9 per 1000 births for Pakistan and 19.9 per 1000 births for Guatemala. From 2010 to 2016, across all sites, the mean stillbirth rate declined from 31.7 per 1000 births to 26.4 per 1000 births for an average annual decline of 3.0%. Risk factors for stillbirth were similar across the sites and included maternal age \u3c 20 years and age \u3e 35 years. Compared to parity 1-2, zero parity and parity \u3e 3 were both associated with increased stillbirth risk and compared to women with any prenatal care, women with no prenatal care had significantly increased risk of stillbirth in all sites.
CONCLUSIONS: At the current rates of decline, stillbirth rates in these sites will not reach the Every Newborn Action Plan goal of 12 per 1000 births by 2030. More attention to the risk factors and treating the causes of stillbirths will be required to reach the Every Newborn Action Plan goal of stillbirth reduction.
TRIAL REGISTRATION: NCT01073475
Challenge of Reducing Perinatal Mortality in Rural Congo: Findings of a Prospective, Population-based Study
Each year, an estimated six million perinatal deaths occur worldwide, and 98% of these deaths occur in lowand middle-income countries. These estimates are based on surveys in both urban and rural areas, and they may underrepresent the problem in rural areas. This study was conducted to quantify perinatal mortality, to identify the associated risk factors, and to determine the most common causes of early neonatal death in a rural area of the Democratic Republic of the Congo (DRC). Data were collected on 1,892 births. Risk factors associated with perinatal deaths were identified using multivariate analysis with logistic regression models. Causes of early neonatal deaths were determined by physician-review of information describing death. The perinatal mortality rate was 61 per 1,000 births; the stillbirth rate was 30 per 1,000 births; and the early neonatal death rate was 32 per 1,000 livebirths. Clinically-relevant factors independently associated with perinatal death included: low birthweight [odds ratio (OR)=13.51, 95% confidence interval (CI) 7.82-23.35], breech presentation (OR)=12.41; 95% CI 4.62-33.33), lack of prenatal care (OR=2.70, 95% CI 1.81-4.02), and parity greater than 4 (OR=1.93 95% CI 1.11-3.37). Over one-half of early neonatal deaths (n=37) occurred during the first two postnatal days, and the most common causes were low birthweight/prematurity (47%), asphyxia (34%), and infection (8%). The high perinatal mortality rate in rural communities in the DRC, approximately one-half of which is attributable to early neonatal death, may be modifiable. Specifically, deaths due to breech presentation, the second most common risk factor, may be reduced by making available emergency obstetric care. Most neonatal deaths occur soon after birth, and nearly three-quarters are caused by low birthweight/prematurity or asphyxia. Neonatal mortality might be reduced by targeting interventions to improve neonatal resuscitation and care of larger preterm infants
Toward a better understanding of task demands, workload, and performance during physician-computer interactions
OBJECTIVE: To assess the relationship between (1) task demands and workload, (2) task demands and performance, and (3) workload and performance, all during physician-computer interactions in a simulated environment.
METHODS: Two experiments were performed in 2 different electronic medical record (EMR) environments: WebCIS (n = 12) and Epic (n = 17). Each participant was instructed to complete a set of prespecified tasks on 3 routine clinical EMR-based scenarios: urinary tract infection (UTI), pneumonia (PN), and heart failure (HF). Task demands were quantified using behavioral responses (click and time analysis). At the end of each scenario, subjective workload was measured using the NASA-Task-Load Index (NASA-TLX). Physiological workload was measured using pupillary dilation and electroencephalography (EEG) data collected throughout the scenarios. Performance was quantified based on the maximum severity of omission errors.
RESULTS: Data analysis indicated that the PN and HF scenarios were significantly more demanding than the UTI scenario for participants using WebCIS (P < .01), and that the PN scenario was significantly more demanding than the UTI and HF scenarios for participants using Epic (P < .01). In both experiments, the regression analysis indicated a significant relationship only between task demands and performance (P < .01).
DISCUSSION: Results suggest that task demands as experienced by participants are related to participants' performance. Future work may support the notion that task demands could be used as a quality metric that is likely representative of performance, and perhaps patient outcomes.
CONCLUSION: The present study is a reasonable next step in a systematic assessment of how task demands and workload are related to performance in EMR-evolving environments
What are the barriers to care integration for those at the advanced stages of dementia living in care homes in the UK? Health care professional perspective
yesPeople with advanced dementia are frequently bed-bound, doubly incontinent and able to speak only a few words. Many reside in care homes and may often have complex needs requiring efficient and timely response by knowledgeable and compassionate staff. The aim of this study is to improve our understanding of health care professionals’ attitudes and knowledge of the barriers to integrated care for people with advanced dementia. In-depth, interactive interviews conducted with 14 health care professionals including commissioners, care home managers, nurses and health care assistants in the UK. Barriers to care for people with advanced dementia are influenced by governmental and societal factors which contribute to challenging environments in care homes, poor morale amongst care staff and a fragmentation of health and social care at the end of life. Quality of care for people with dementia as they approach death may be improved by developing collaborative networks to foster improved relationships between health and social care services
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