scholarly journals Empirical Priors and Coverage of Posterior Credible Sets in a Sparse Normal Mean Model

Sankhya A ◽  
2019 ◽  
Vol 82 (2) ◽  
pp. 477-498
Author(s):  
Ryan Martin ◽  
Bo Ning
Keyword(s):  
Credible Sets ◽  
Normal Mean ◽  
Empirical Priors

Very Low Activated Factor VII and Reduced Factor VII Antigen in Familial Abetalipoproteinaemia

1998 ◽  
Vol 80 (08) ◽  
pp. 233-238 ◽  
Author(s):  
K. A. Mitropoulos ◽  
M. N. Nanjee ◽  
D. J. Howarth ◽  
J. C. Martin ◽  
M. P. Esnouf ◽  
...  
Keyword(s):  
Plasma Concentrations ◽  
Positive Association ◽  
Factor Ix ◽  
Factor Vii ◽  
Unesterified Fatty Acid ◽  
Factor Xii ◽  
Factor X ◽  
Factor Xi ◽  
Activated Factor Vii ◽  
Normal Mean

SummaryAbetalipoproteinaemia is a rare disorder of apolipoprotein B metabolism associated with extremely low plasma concentrations of triglyce-ride. To discover whether the general positive association between factor VII and triglyceride levels extends to this condition, 5 patients were compared with 18 controls. All patients had a triglyceride below 100 μmol/l. Plasma unesterified fatty acid concentration was normal. Although factor IX activity was only slightly reduced (mean 88% standard) and factor IX antigen was normal, mean activated factor VII in patients was strikingly reduced to 34% of that in controls, a level similar to that found in haemophilia B. The patients’ mean factor VII activity and factor VII antigen were also significantly reduced to 54% and 63% of those in controls, respectively. Mean factor XI activity and tissue factor pathway inhibitor activity were reduced in patients to 70% and 75% of control values respectively, while factor XII, factor XI antigen, factor X, prothrombin and protein C were normal.

scholarly journals Comparing the use of aggregate data and various methods of integrating individual patient data to network meta-analysis and its application to first-line ART

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Steve Kanters ◽  
Mohammad Ehsanul Karim ◽  
Kristian Thorlund ◽  
Aslam H. Anis ◽  
Michael Zoratti ◽  
...  
Keyword(s):  
Meta Analysis ◽  
Evidence Base ◽  
Aggregate Data ◽  
World Health ◽  
Coefficient Estimates ◽  
Two Stage ◽  
Individual Patient Level ◽  
One Stage ◽  
Meta Regression ◽  
Empirical Priors

Abstract Background The 2018 World Health Organization HIV guidelines were based on the results of a network meta-analysis (NMA) of published trials. This study employed individual patient-level data (IPD) and aggregate data (AgD) and meta-regression methods to assess the evidence supporting the WHO recommendations and whether they needed any refinements. Methods Access to IPD from three trials was granted through ClinicalStudyDataRequest.com (CSDR). Seven modelling approaches were applied and compared: 1) Unadjusted AgD network meta-analysis (NMA) – the original analysis; 2) AgD-NMA with meta-regression; 3) Two-stage IPD-AgD NMA; 4) Unadjusted one-stage IPD-AgD NMA; 5) One-stage IPD-AgD NMA with meta-regression (one-stage approach); 6) Two-stage IPD-AgD NMA with empirical-priors (empirical-priors approach); 7) Hierarchical meta-regression IPD-AgD NMA (HMR approach). The first two were the models used previously. Models were compared with respect to effect estimates, changes in the effect estimates, coefficient estimates, DIC and model fit, rankings and between-study heterogeneity. Results IPD were available for 2160 patients, representing 6.5% of the evidence base and 3 of 24 edges. The aspect of the model affected by the choice of modeling appeared to differ across outcomes. HMR consistently generated larger intervals, often with credible intervals (CrI) containing the null value. Discontinuations due to adverse events and viral suppression at 96 weeks were the only two outcomes for which the unadjusted AgD NMA would not be selected. For the first, the selected model shifted the principal comparison of interest from an odds ratio of 0.28 (95% CrI: 10.17, 0.44) to 0.37 (95% CrI: 0.23, 0.58). Throughout all outcomes, the regression estimates differed substantially between AgD and IPD methods, with the latter being more often larger in magnitude and statistically significant. Conclusions Overall, the use of IPD often impacted the coefficient estimates, but not sufficiently as to necessitate altering the final recommendations of the 2018 WHO Guidelines. Future work should examine the features of a network where adjustments will have an impact, such as how much IPD is required in a given size of network.

Rabbit aortic medial thickness under relaxed and specified simulated in vivo conditions

1983 ◽  
Vol 245 (4) ◽  
pp. H623-H627
Author(s):  
G. Schneiderman ◽  
W. F. Pritchard ◽  
C. A. Ramirez ◽  
C. K. Colton ◽  
K. A. Smith ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Mean Arterial Pressure ◽  
Aortic Wall ◽  
Macromolecular Transport ◽  
Liquid Silicone ◽  
Normal Mean ◽  
Longitudinal Extension ◽  
Media Layer

A method is presented for measuring the thickness of the intima-media layer of the normal rabbit descending thoracic aortic wall under both relaxed (excised) and specified simulated in vivo conditions. The in vivo conditions were simulated by maintaining the aorta in situ at its normal longitudinal extension while perfusing its lumen at the normal mean arterial pressure with a mixture of liquid silicone polymer and a catalyst, thus providing physiological radial distension. After the rubber cured, both relaxed and extended-distended tissue segments were obtained from adjacent sites on the same aorta. These tissue segments were fixed and further processed for measurement of their medial thicknesses by light microscopy. This data was used to estimate the ratio of the medial thickness of the relaxed, excised aorta to that under in vivo conditions, 1.72 +/- 0.15. This information is required for quantitative analysis of data obtained from previous studies of in vivo macromolecular transport across the rabbit thoracic aortic wall.

scholarly journals CAUSALdb: a database for disease/trait causal variants identified using summary statistics of genome-wide association studies

2019 ◽  
Author(s):  
Jianhua Wang ◽  
Dandan Huang ◽  
Yao Zhou ◽  
Hongcheng Yao ◽  
Huanhuan Liu ◽  
...  
Keyword(s):  
Fine Mapping ◽  
Genetic Variants ◽  
Association Studies ◽  
Complex Trait ◽  
Genome Wide Association ◽  
Genome Wide Association Studies ◽  
Summary Statistics ◽  
Genome Wide ◽  
Credible Sets ◽  
Causal Variants

Abstract Genome-wide association studies (GWASs) have revolutionized the field of complex trait genetics over the past decade, yet for most of the significant genotype-phenotype associations the true causal variants remain unknown. Identifying and interpreting how causal genetic variants confer disease susceptibility is still a big challenge. Herein we introduce a new database, CAUSALdb, to integrate the most comprehensive GWAS summary statistics to date and identify credible sets of potential causal variants using uniformly processed fine-mapping. The database has six major features: it (i) curates 3052 high-quality, fine-mappable GWAS summary statistics across five human super-populations and 2629 unique traits; (ii) estimates causal probabilities of all genetic variants in GWAS significant loci using three state-of-the-art fine-mapping tools; (iii) maps the reported traits to a powerful ontology MeSH, making it simple for users to browse studies on the trait tree; (iv) incorporates highly interactive Manhattan and LocusZoom-like plots to allow visualization of credible sets in a single web page more efficiently; (v) enables online comparison of causal relations on variant-, gene- and trait-levels among studies with different sample sizes or populations and (vi) offers comprehensive variant annotations by integrating massive base-wise and allele-specific functional annotations. CAUSALdb is freely available at http://mulinlab.org/causaldb.

scholarly journals Over one third of patients with symptomatic femoroacetabular impingement display femoral or acetabular version abnormalities

2021 ◽  
Author(s):  
Zaki Arshad ◽  
Henry David Maughan ◽  
Karadi Hari Sunil Kumar ◽  
Matthew Pettit ◽  
Arvind Arora ◽  
...  
Keyword(s):  
Clinical Decision Making ◽  
Clinical Decision ◽  
Original Research ◽  
Distribution Analysis ◽  
Inclusion Criteria ◽  
Acetabular Version ◽  
Level Of Evidence ◽  
Femoral Version ◽  
Normal Mean ◽  
The Relationship

Abstract Purpose The aim of this study was investigate the relationship between version and torsional abnormalities of the acetabulum, femur and tibia in patients with symptomatic FAI. Methods A systematic review was performed according to PRISMA guidelines using the EMBASE, MEDLINE, PubMed and Cochrane databases. Original research articles evaluating the described version and torsional parameters in FAI were included. The MINORS criteria were used to appraise study quality and risk of bias. Mean version and torsion values were displayed using forest plots and the estimated proportion of hips displaying abnormalities in version/torsion were calculated. Results A total of 1206 articles were identified from the initial search, with 43 articles, involving 8861 hips, meeting the inclusion criteria. All studies evaluating femoral or acetabular version in FAI reported ‘normal’ mean version values (10–25 °). However, distribution analysis revealed that an estimated 31% and 51% of patients with FAI displayed abnormal central acetabular and femoral version, respectively. Conclusion Up to 51% of patients presenting with symptomatic FAI show an abnormal femoral version, whilst up to 31% demonstrate abnormal acetabular version. This high percentage of version abnormalities highlights the importance of evaluating these parameters routinely during assessment of patients with FAI, to guide clinical decision-making. Level of evidence IV.

scholarly journals Targeting low-normal or high-normal mean arterial pressure after cardiac arrest and resuscitation: a randomised pilot trial

2018 ◽  
Vol 44 (12) ◽  
pp. 2091-2101 ◽  
Author(s):  
Pekka Jakkula ◽  
◽  
Ville Pettilä ◽  
Markus B. Skrifvars ◽  
Johanna Hästbacka ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Mean Arterial Pressure ◽  
Arterial Pressure ◽  
Pilot Trial ◽  
Normal Mean

Uptake of exogenous substrates during hypoxia in fetal lambs

1988 ◽  
Vol 254 (5) ◽  
pp. E572-E578 ◽  
Author(s):  
J. R. Milley
Keyword(s):  
Umbilical Vein ◽  
Amino Nitrogen ◽  
Metabolic Substrates ◽  
Umbilical Blood ◽  
Accretion Rates ◽  
Normal Mean ◽  
Microsphere Method ◽  
Near Term ◽  
Normal Nitrogen ◽  
Exogenous Substrates

Fetal uptakes of oxygen, glucose, lactate, and alpha-amino-nitrogen containing substrates were measured in eight near-term fetal lambs by simultaneously drawing blood samples from the umbilical vein and descending aorta, then measuring umbilical blood flow using the microsphere method. These procedures were repeated after 3 h of hypoxia induced by lowering maternal inspired oxygen concentration. On the next day the experiment was repeated, except the ewes were first made hypoxic then allowed to breathe room air. These conditions decreased the delivery of oxygen, but not the delivery of other metabolic substrates to the fetus. During hypoxia, fetal oxygen uptake was 82% of normal (mean of both days); fetal glucose and amino-nitrogen uptakes were 74 and 23% of normal, respectively, and fetal lactate uptake became insignificant. These data indicate that endogenous rather than exogenous substrates are used to support fetal oxidative metabolism during hypoxia. Also, because exogenous uptake of amino-nitrogen is less than normal nitrogen accretion rates, fetal growth must be reduced as a consequence of 3-4 h of hypoxia.

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