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Global Analysis of Genetic, Epigenetic and Transcriptional Polymorphisms in <i>Arabidopsis thaliana</i> Using Whole Genome Tiling Arrays
Whole genome tiling arrays provide a high resolution platform for profiling of genetic, epigenetic, and gene expression polymorphisms. In this study we surveyed natural genomic variation in cytosine methylation among Arabidopsis thaliana wild accessions Columbia (Col) and Vancouver (Van) by comparing hybridization intensity difference between genomic DNA digested with either methylation-sensitive (HpaII) or -insensitive (MspI) restriction enzyme. Single Feature Polymorphisms (SFPs) were assayed on a full set of 1,683,620 unique features of Arabidopsis Tiling Array 1.0F (Affymetrix), while constitutive and polymorphic CG methylation were assayed on a subset of 54,519 features, which contain a 5′CCGG3′ restriction site. 138,552 SFPs (1% FDR) were identified across enzyme treatments, which preferentially accumulated in pericentromeric regions. Our study also demonstrates that at least 8% of all analyzed CCGG sites were constitutively methylated across the two strains, while about 10% of all analyzed CCGG sites were differentially methylated between the two strains. Within euchromatin arms, both constitutive and polymorphic CG methylation accumulated in central regions of genes but under-represented toward the 5′ and 3′ ends of the coding sequences. Nevertheless, polymorphic methylation occurred much more frequently in gene ends than constitutive methylation. Inheritance of methylation polymorphisms in reciprocal F1 hybrids was predominantly additive, with F1 plants generally showing levels of methylation intermediate between the parents. By comparing gene expression profiles, using matched tissue samples, we found that magnitude of methylation polymorphism immediately upstream or downstream of the gene was inversely correlated with the degree of expression variation for that gene. In contrast, methylation polymorphism within genic region showed weak positive correlation with expression variation. Our results demonstrated extensive genetic and epigenetic polymorphisms between Arabidopsis accessions and suggested a possible relationship between natural CG methylation variation and gene expression variation.</p
Volume Assessment in Mechanically Ventilated Critical Care Patients Using Bioimpedance Vectorial Analysis, Brain Natriuretic Peptide, and Central Venous Pressure
Purpose. Strategies for volume assessment of critically ill patients are limited, yet early goal-directed therapy improves outcomes. Central venous pressure (CVP), Bioimpedance Vectorial Analysis (BIVA), and brain natriuretic peptide (BNP) are potentially useful tools. We studied the utility of these measures, alone and in combination, to predict changing oxygenation. Methods. Thirty-four mechanically ventilated patients, 26 of whom had data beyond the first study day, were studied. Relationships were assessed between CVP, BIVA, BNP, and oxygenation index (O2I) in a cross-sectional (baseline) and longitudinal fashion using both univariate and multivariable modeling. Results. At baseline, CVP and O2I were positively correlated (R = 0.39; P = .021), while CVP and BIVA were weakly correlated (R = −0.38; P = .025). The association between slopes of variables over time was negligible, with the exception of BNP, whose slope was correlated with O2I (R = 0.40; P = .044). Comparing tertiles of CVP, BIVA, and BNP slopes with the slope of O2I revealed only modest agreement between BNP and O2I (kappa = 0.25; P = .067). In a regression model, only BNP was significantly associated with O2I; however, this was strengthened by including CVP in the model. Conclusions. BNP seems to be a valuable noninvasive measure of volume status in critical care and should be assessed in a prospective manner
Unknowable bodies, unthinkable sexualities: lesbian and transgender legal invisibility in the Toronto women's bathhouse raid
Although litigation involving sexual orientation and gender identity discrimination claims has generated considerable public attention in recent years, lesbian and transgender bodies and sexualities still remain largely invisible in Anglo-American courts. While such invisibility is generally attributed to social norms that fail to recognize lesbian and transgender experiences, the capacity to 'not see' or 'not know' queer bodies and sexualities also involves wilful acts of ignorance. Drawing from R. v Hornick (2002) a Canadian case involving the police raid of a women's bathhouse, this article explores how lesbian and transgender bodies and sexualities are actively rendered invisible via legal knowledge practices, norms and rationalities. It argues that limited knowledge and limited thinking not only regulate the borders of visibility and belonging, but play an active part in shaping identities, governing conduct and producing subjectivity
Heart-Kidney Biomarkers in Patients Undergoing Cardiac Stress Testing
We examined association of inducible myocardial perfusion defects with cardiorenal biomarkers, and of diminished left ventricular ejection fraction (LVEF) with kidney injury marker plasma neutrophil gelatinase-associated lipocalin (NGAL). Patients undergoing nuclear myocardial perfusion stress imaging were divided into 2 groups. Biomarkers were analyzed pre- and poststress testing. Compared to the patients in the low ischemia group (n = 16), the patients in the high ischemia group (n = 18) demonstrated a significantly greater rise in cardiac biomarkers plasma BNP, NT-proBNP and cTnI. Subjects were also categorized based on pre- or poststress test detectable plasma NGAL. With stress, the group with no detectable NGAL had a segmental defect score 4.2 compared to 8.2 (P = .06) in the detectable NGAL group, and 0.9 vs. 3.8 (P = .03) at rest. BNP rose with stress to a greater degree in patients with detectable NGAL (10.2 vs. 3.5 pg/mL, P = .03). LVEF at rest and with stress was significantly lower in the detectable NGAL group; 55.8 versus 65.0 (P = .03) and 55.1 vs. 63.8 (P = .04), respectively. Myocardial perfusion defects associate with biomarkers of cardiac stress, and detectable plasma NGAL with significantly lower LVEF, suggesting a specific heart-kidney link
B-Type Natriuretic Peptide in the Critically Ill with Acute Kidney Injury
Introduction. Acute kidney injury (AKI) is common in the intensive care unit (ICU) and associated with poor outcome. Plasma B-type natriuretic peptide (BNP) is a biomarker related to myocardial overload, and is elevated in some ICU patients. There is a high prevalence of both cardiac and renal dysfunction in ICU patients. Aims. To investigate whether plasma BNP levels in the first 48 hours were associated with AKI in ICU patients. Methods. We studied a cohort of 34 consecutive ICU patients. Primary outcome was presence of AKI on presentation, or during ICU stay. Results. For patients with AKI on presentation, BNP was statistically higher at 24 and 48 hours than No-AKI patients (865 versus 148 pg/mL; 1380 versus 131 pg/mL). For patients developing AKI during 48 hours, BNP was statistically higher at 0, 24 and 48 hours than No-AKI patients (510 versus 197 pg/mL; 552 versus 124 pg/mL; 949 versus 104 pg/mL). Conclusion. Critically ill patients with AKI on presentation or during ICU stay have higher levels of the cardiac biomarker BNP relative to No-AKI patients. Elevated levels of plasma BNP may help identify patients with elevated risk of AKI in the ICU setting. The mechanism for this cardiorenal connection requires further investigation
Beyond Undetectable: Modeling the Clinical Benefit of Improved Antiretroviral Adherence in Persons With Human Immunodeficiency Virus With Virologic Suppression
BACKGROUND: Incomplete antiretroviral therapy (ART) adherence has been linked to deleterious immunologic, inflammatory, and clinical consequences, even among virally suppressed (<50 copies/mL) persons with human immunodeficiency virus (PWH). The impact of improving adherence in the risk of severe non-AIDS events (SNAEs) and death in this population is unknown. METHODS: We estimated the reduction in the risk of SNAEs or death resulting from an increase in ART adherence by (1) applying existing data on the association between adherence with high residual inflammation/coagulopathy in virally suppressed PWH, and (2) using a Cox proportional hazards model derived from changes in plasma interleukin 6 (IL-6) and D-dimer from 3 randomized clinical trials. Comparatively, assuming 100% ART adherence in a PWH who achieves viral suppression, we estimated the number of persons in whom a decrease in adherence to <100% would need to be observed for an additional SNAE or death event to occur during 3- and 5-year follow-up. RESULTS: Increasing ART adherence to 100% in PWH who are suppressed on ART despite imperfect adherence translated into a 6%-37% reduction in the risk of SNAEs or death. Comparatively, based on an anticipated 12% increase in IL-6, 254 and 165 PWH would need to decrease their adherence from 100% to <100% for an additional event to occur over 3- and 5-year follow-up, respectively. CONCLUSIONS: Modest gains in ART adherence could have clinical benefits beyond virologic suppression. Increasing ART adherence (eg, via an intervention or switch to long-acting ART) in PWH who remain virally suppressed despite incomplete adherence should be evaluated
School-based systems change for obesity prevention in adolescents: Outcomes of the Australian Capital Territory 'It's Your Move!'
Objective: The Australian Capital Territory ‘It’s Your Move!’ (ACT-IYM) was a three-year (2012-
2014) systems intervention to prevent obesity among adolescents.
Methods: The ACT-IYM project involved three intervention schools and three comparison
schools and targeted secondary students aged 12-16 years. The intervention consisted of
multiple initiatives at individual, community, and school policy level to support healthier
nutrition and physical activity. Intervention school-specific objectives related to increasing
active transport, increasing time spent physically active at school, and supporting mental
wellbeing. Data were collected in 2012 and 2014 from 656 students. Anthropometric data were
objectively measured and behavioural data self-reported.
Results: Proportions of overweight or obesity were similar over time within the intervention
(24.5% baseline and 22.8% follow-up) and comparison groups (31.8% baseline and 30.6%
follow-up). Within schools, two of three the intervention schools showed a significant decrease in the prevalence of overweight and obesity (p<0.05).
Conclusions: There was some evidence of effectiveness of the systems approach to preventing obesity among adolescents. Implications for public health: The incorporation of systems thinking has been touted as the
next stage in obesity prevention and public health more broadly. These findings demonstrate
that the use of systems methods can be effective on a small scale.
Key words: Adolescence, systems intervention, obesity, weight status, schools, health
promotionThis program was a joint Australian,
State and Territory Government initiative
under the National Partnership Agreement on
Preventative Healt
ScreenTrack: Using a Visual History of a Computer Screen to Retrieve Documents and Web Pages
Computers are used for various purposes, so frequent context switching is
inevitable. In this setting, retrieving the documents, files, and web pages
that have been used for a task can be a challenge. While modern applications
provide a history of recent documents for users to resume work, this is not
sufficient to retrieve all the digital resources relevant to a given primary
document. The histories currently available do not take into account the
complex dependencies among resources across applications. To address this
problem, we tested the idea of using a visual history of a computer screen to
retrieve digital resources within a few days of their use through the
development of ScreenTrack. ScreenTrack is software that captures screenshots
of a computer at regular intervals. It then generates a time-lapse video from
the captured screenshots and lets users retrieve a recently opened document or
web page from a screenshot after recognizing the resource by its appearance. A
controlled user study found that participants were able to retrieve requested
information more quickly with ScreenTrack than under the baseline condition
with existing tools. A follow-up study showed that the participants used
ScreenTrack to retrieve previously used resources and to recover the context
for task resumption.Comment: CHI 2020, 10 pages, 7 figure
Global Analysis of Genetic, Epigenetic and Transcriptional Polymorphisms in Arabidopsis thaliana Using Whole Genome Tiling Arrays
Whole genome tiling arrays provide a high resolution platform for profiling of genetic, epigenetic, and gene expression polymorphisms. In this study we surveyed natural genomic variation in cytosine methylation among Arabidopsis thaliana wild accessions Columbia (Col) and Vancouver (Van) by comparing hybridization intensity difference between genomic DNA digested with either methylation-sensitive (HpaII) or -insensitive (MspI) restriction enzyme. Single Feature Polymorphisms (SFPs) were assayed on a full set of 1,683,620 unique features of Arabidopsis Tiling Array 1.0F (Affymetrix), while constitutive and polymorphic CG methylation were assayed on a subset of 54,519 features, which contain a 5′CCGG3′ restriction site. 138,552 SFPs (1% FDR) were identified across enzyme treatments, which preferentially accumulated in pericentromeric regions. Our study also demonstrates that at least 8% of all analyzed CCGG sites were constitutively methylated across the two strains, while about 10% of all analyzed CCGG sites were differentially methylated between the two strains. Within euchromatin arms, both constitutive and polymorphic CG methylation accumulated in central regions of genes but under-represented toward the 5′ and 3′ ends of the coding sequences. Nevertheless, polymorphic methylation occurred much more frequently in gene ends than constitutive methylation. Inheritance of methylation polymorphisms in reciprocal F1 hybrids was predominantly additive, with F1 plants generally showing levels of methylation intermediate between the parents. By comparing gene expression profiles, using matched tissue samples, we found that magnitude of methylation polymorphism immediately upstream or downstream of the gene was inversely correlated with the degree of expression variation for that gene. In contrast, methylation polymorphism within genic region showed weak positive correlation with expression variation. Our results demonstrated extensive genetic and epigenetic polymorphisms between Arabidopsis accessions and suggested a possible relationship between natural CG methylation variation and gene expression variation
Fast visible imaging of ELM-wall interactions on JET
We present and discuss recent measurements of the fast imaging diagnostic in JET. We focus on wide angle observations of few large ELM events (Delta W-ELM similar to 700 kJ) in plasmas with high current, magnetic field and stored energy (similar to 3 T, 3 MA, 8 MJ). Measurements were taken at recording speeds around 30 kHz. The ELM-wall interaction shows a filamentary structure that appears together with the radiation increase in the divertor, implying similar times of flight for ELM radial and parallel transport in the SOL, tau(11) - tau(r), within a time resolution of 30 mu s. Two high and low triangularity cases are compared. For high triangularity the ELM-wall interaction is seen to start in the upper dump plate reaching the outer limiters some 70 mu s later. In the low triangularity cases interaction generally starts in the outer wall but clear evidence of radiation increase in the upper dump plate is seen shortly after (30 Its) or together with the first filament impact on the outer limiters. A poloidal drift of the filament strike point on the limiters is sometimes visible which allows an estimation of the perpendicular filament velocity (similar to 1 km/s). (C) 2009 Elsevier B.V. All rights reserved
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