74 research outputs found
Adenovirus type 5 exerts genome-wide control over cellular programs governing proliferation, quiescence, and survival
The effects of the adenovirus Ad5 on basic host cell programs, such as cell-cycle regulation, were studied in a microarray analysis of human fibroblasts. About 2,000 genes were up- or down-regulated after Ad5 infection and Ad5 infection was shown to induce reversal of the quiescence program and recapitulation of the core serum response
Structure and uncoating of immature adenovirus
Maturation via proteolytical processing is a common trait in the viral world, and is
often accompanied by large conformational changes and rearrangements in the capsid.
The adenovirus protease has been shown to play a dual role in the viral infectious
cycle: (a) in maturation, as viral assembly starts with precursors to several of the
structural proteins, but ends with proteolytically processed versions in the mature
virion; and (b) in entry, because protease-impaired viruses have difficulties in
endosome escape and uncoating. Indeed, viruses that have not undergone proteolytical
processing are not infectious. We present the 3D structure of immature adenovirus
particles, as represented by the thermosensitive mutant Ad2 ts1 grown under nonpermissive
conditions, and compare it with the mature capsid. Our 3DEM maps at
subnanometer resolution indicate that adenovirus maturation does not involve large
scale conformational changes in the capsid. Difference maps reveal the location of
unprocessed peptides pIIIa and pVI and help to define their role in capsid assembly
and maturation. An intriguing difference appears in the core, indicating a more
compact organization and increased stability of the immature cores. We have further
investigated these properties by in vitro disassembly assays. Fluorescence and
electron microscopy experiments reveal differences in the stability and uncoating of
immature viruses, both at the capsid and core levels, as well as disassembly
intermediates not previously imaged.This work was supported by grants from the Ministerio de Ciencia e InnovaciĂłn of Spain (BFU2007-60228 to C.S.M. and BIO2007-67150-C03-03 to R.M.), the Comunidad AutĂłnoma de Madrid and Consejo Superior de Investigaciones CientĂficas (CCG08-CSIC/SAL-3442 to C.S.M.) and the National Institutes of Health (5R01CA111569 to D.T.C., R0141599 to W.F.M. and GM037705 to S.J.F.). R.M.-C. is a recipient of a PFIS fellowship from the Instituto de Salud Carlos III of Spain. A.J.P.-B. holds a CSIC JAE-Doc postdoctoral position, partially funded by the European Social FundPeer reviewe
Participatory Process for Implementing a Colorectal Cancer Screening Intervention: an Action Plan for Local Sustainability
Background: Rigid protocols can hamper translation of evidence-based interventions from research to real-world settings. This investigation aimed to develop procedures for modifying the study protocol of a community-based participatory research (CBPR) project and to analyze the theoretical constructs that underlie this process.
Methods: The research project is a dissemination and implementation study of the Educational Program to Increase Colorectal Cancer Screening (EPICS), an evidence-based intervention targeting African Americans in the United States. The study is being conducted in a partnership with community coalitions in 15 different cities. Each site initially presented unique issues that required modification of the study protocol.
Results: In order to honor underlying CBPR theory, it was necessary to negotiate protocol changes with the community coalition at each site, while insuring preservation of the core elements of the intervention.
Conclusions: We discuss the ways in which this represents a narrowing of the gap between CBPR and traditional research approaches
The effect of artificial selection on phenotypic plasticity in maize
Remarkable productivity has been achieved in crop species through artificial selection and adaptation to modern agronomic practices. Whether intensive selection has changed the ability of improved cultivars to maintain high productivity across variable environments is unknown. Understanding the genetic control of phenotypic plasticity and genotype by environment (G Ă E) interaction will enhance crop performance predictions across diverse environments. Here we use data generated from the Genomes to Fields (G2F) Maize G Ă E project to assess the effect of selection on G Ă E variation and characterize polymorphisms associated with plasticity. Genomic regions putatively selected during modern temperate maize breeding explain less variability for yield G Ă E than unselected regions, indicating that improvement by breeding may have reduced G Ă E of modern temperate cultivars. Trends in genomic position of variants associated with stability reveal fewer genic associations and enrichment of variants 0â5000 base pairs upstream of genes, hypothetically due to control of plasticity by short-range regulatory elements
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Association between Class III Obesity (BMI of 40â59 kg/m2) and Mortality: A Pooled Analysis of 20 Prospective Studies
Background: The prevalence of class III obesity (body mass index [BMI]â„40 kg/m2) has increased dramatically in several countries and currently affects 6% of adults in the US, with uncertain impact on the risks of illness and death. Using data from a large pooled study, we evaluated the risk of death, overall and due to a wide range of causes, and years of life expectancy lost associated with class III obesity. Methods and Findings: In a pooled analysis of 20 prospective studies from the United States, Sweden, and Australia, we estimated sex- and age-adjusted total and cause-specific mortality rates (deaths per 100,000 persons per year) and multivariable-adjusted hazard ratios for adults, aged 19â83 y at baseline, classified as obese class III (BMI 40.0â59.9 kg/m2) compared with those classified as normal weight (BMI 18.5â24.9 kg/m2). Participants reporting ever smoking cigarettes or a history of chronic disease (heart disease, cancer, stroke, or emphysema) on baseline questionnaires were excluded. Among 9,564 class III obesity participants, mortality rates were 856.0 in men and 663.0 in women during the study period (1976â2009). Among 304,011 normal-weight participants, rates were 346.7 and 280.5 in men and women, respectively. Deaths from heart disease contributed largely to the excess rates in the class III obesity group (rate differences = 238.9 and 132.8 in men and women, respectively), followed by deaths from cancer (rate differences = 36.7 and 62.3 in men and women, respectively) and diabetes (rate differences = 51.2 and 29.2 in men and women, respectively). Within the class III obesity range, multivariable-adjusted hazard ratios for total deaths and deaths due to heart disease, cancer, diabetes, nephritis/nephrotic syndrome/nephrosis, chronic lower respiratory disease, and influenza/pneumonia increased with increasing BMI. Compared with normal-weight BMI, a BMI of 40â44.9, 45â49.9, 50â54.9, and 55â59.9 kg/m2 was associated with an estimated 6.5 (95% CI: 5.7â7.3), 8.9 (95% CI: 7.4â10.4), 9.8 (95% CI: 7.4â12.2), and 13.7 (95% CI: 10.5â16.9) y of life lost. A limitation was that BMI was mainly ascertained by self-report. Conclusions: Class III obesity is associated with substantially elevated rates of total mortality, with most of the excess deaths due to heart disease, cancer, and diabetes, and major reductions in life expectancy compared with normal weight. Please see later in the article for the Editors' Summar
Immune response CC chemokines CCL2 and CCL5 are associated with pulmonary sarcoidosis
Abstract Background Pulmonary sarcoidosis involves an intense leukocyte infiltration of the lung with the formation of non-necrotizing granulomas. CC chemokines (chemokine (C-C motif) ligand 2 (CCL2)-CCL5) are chemoattractants of mononuclear cells and act through seven transmembrane G-coupled receptors. Previous studies have demonstrated conflicting results with regard to the associations of these chemokines with sarcoidosis. In an effort to clarify previous discrepancies, we performed the largest observational study to date of CC chemokines in bronchoalveolar lavage fluid (BALF) from patients with pulmonary sarcoidosis. Results BALF chemokine levels from 72 patients affected by pulmonary sarcoidosis were analyzed by enzyme-linked immunosorbent assay (ELISA) and compared to 8 healthy volunteers. BALF CCL3 and CCL4 levels from pulmonary sarcoidosis patients were not increased compared to controls. However, CCL2 and CCL5 levels were elevated, and subgroup analysis showed higher levels of both chemokines in all stages of pulmonary sarcoidosis. CCL2, CCL5, CC chemokine receptor type 1 (CCR1), CCR2 and CCR3 were expressed from mononuclear cells forming the lung granulomas, while CCR5 was only found on mast cells. Conclusions These data suggest that CCL2 and CCL5 are important mediators in recruiting CCR1, CCR2, and CCR3 expressing mononuclear cells as well as CCR5-expressing mast cells during all stages of pulmonary sarcoidosis
Contrasting Views of the Post-bariatric Surgery Experience between Patients and their Practitioners: a Qualitative Study
© 2018, The Author(s). Background: The superiority of obesity surgery for improving medical and weight outcomes in severely obese patients when compared to other weight loss interventions remains undisputed. However, knowledge about the psychological impact of the procedure on patientsâ lives is limited. Systematic reviews indicate persisting psychological distress after surgery compared to control groups especially longer term, suggesting the need for postoperative psychological support and assessment. Research literature also infers limited knowledge regarding the postoperative patient experience of obesity surgery. This may form a barrier in health practitionersâ understanding of these patientsâ ongoing needs. Methods: Ten patients who had obesity surgery two or more years ago and eight obesity surgery practitioners were recruited within hospital settings and individually interviewed by the researcher to capture their accounts of the postoperative experience. Concordance between the two groups was explored to gauge awareness of patientsâ subsequent health needs. Results: Thematic analysis of transcribed interviews elicited a key finding around âpost-surgical cliffs in patient careâ within a heavily structured service. Participants reported some unmet needs, namely, psychological aftercare to facilitate adjustment following drastic weight loss and excess skin, acceptance of their non-obese self and perceived stigma. The impact of contrasting views of success between patients and practitioners on postoperative care within the service context was highlighted. Conclusions: Obesity surgery is a great weight loss catalyst for severe obesity. However, lack of psychological aftercare may threaten early gains in health outcomes over the longer term. More qualitative and quantitative studies are needed to validate current study results
Ebola virus epidemiology, transmission, and evolution during seven months in Sierra Leone
The 2013-2015 Ebola virus disease (EVD) epidemic is caused by the Makona variant of Ebola virus (EBOV). Early in the epidemic, genome sequencing provided insights into virus evolution and transmission and offered important information for outbreak response. Here, we analyze sequences from 232 patients sampled over 7 months in Sierra Leone, along with 86 previously released genomes from earlier in the epidemic. We confirm sustained human-to-human transmission within Sierra Leone and find no evidence for import or export of EBOV across national borders after its initial introduction. Using high-depth replicate sequencing, we observe both host-to-host transmission and recurrent emergence of intrahost genetic variants. We trace the increasing impact of purifying selection in suppressing the accumulation of nonsynonymous mutations over time. Finally, we note changes in the mucin-like domain of EBOV glycoprotein that merit further investigation. These findings clarify the movement of EBOV within the region and describe viral evolution during prolonged human-to-human transmission
Sixteen diverse laboratory mouse reference genomes define strain-specific haplotypes and novel functional loci.
We report full-length draft de novo genome assemblies for 16 widely used inbred mouse strains and find extensive strain-specific haplotype variation. We identify and characterize 2,567 regions on the current mouse reference genome exhibiting the greatest sequence diversity. These regions are enriched for genes involved in pathogen defence and immunity and exhibit enrichment of transposable elements and signatures of recent retrotransposition events. Combinations of alleles and genes unique to an individual strain are commonly observed at these loci, reflecting distinct strain phenotypes. We used these genomes to improve the mouse reference genome, resulting in the completion of 10 new gene structures. Also, 62 new coding loci were added to the reference genome annotation. These genomes identified a large, previously unannotated, gene (Efcab3-like) encoding 5,874 amino acids. Mutant Efcab3-like mice display anomalies in multiple brain regions, suggesting a possible role for this gene in the regulation of brain development
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