137 research outputs found
THREE DIMENSIONAL RECONSTRUCTION OF THE COMPONENTS OF THE CAROTID PLAQUE FROM STANDARD CT MEDICAL IMAGES
ABSTRACT The present study compares plaque and calcium volumes between sixteen diseased human carotid arteries. Half were from symptomatic patients, and half were from asymptomatic patients. In-house software was developed for the 3-D reconstruction of the plaque components from computerized tomography (CT) images. Results revealed higher mean total volume (TV) in the symptomatic group compared to the asymptomatic group. In contrast, the mean ratio of calcium volume (CV) to TV was lower for the symptomatic group compared to the asymptomatic group. This shows that symptomatic patients have a significantly greater plaque burden with minimal plaque calcification. The process of acquiring the data helped understand what tools/features are needed to conduct this work. One important feature of this software is the ability to create automated regions of interest (ROI) in addition to simple manual selection/modification of the ROIs in a GUI environment
Recommended from our members
Task-Specific and General Cognitive Effects in Chiari Malformation Type I
Objective
Our objective was to use episodic memory and executive function tests to determine whether or not Chiari Malformation Type I (CM) patients experience cognitive dysfunction.
Background
CM is a neurological syndrome in which the cerebellum descends into the cervical spine causing neural compression, severe headaches, neck pain, and number of other physical symptoms. While primarily a disorder of the cervico-medullary junction, both clinicians and researchers have suspected deficits in higher-level cognitive function.
Design and Methods
We tested 24 CM patients who had undergone decompression neurosurgery and 24 age- and education-matched controls on measures of immediate and delayed episodic memory, as well as three measures of executive function.
Results
The CM group showed performance decrements relative to the controls in response inhibition (Stroop interference), working memory computational speed (Ospan), and processing speed (automated digit symbol substitution task), but group differences in recall did not reach statistical significance. After statistical control for depression and anxiety scores, the group effects for working memory and processing speed were eliminated, but not for response inhibition. This response inhibition difference was not due to overall general slowing for the CM group, either, because when controls' data were transformed using the linear function fit to all of the reaction time tasks, the interaction with group remained statistically significant. Furthermore, there was a multivariate group effect for all of the response time measures and immediate and delayed recall after statistical control of depression and anxiety scores.
Conclusion
These results suggest that CM patients with decompression surgery exhibit cognitive dysfunction compared to age- and education-matched controls. While some of these results may be related to anxiety and depression (likely proxies for chronic pain), response inhibition effects, in particular, as well as a general cognitive deficit persisted even after control for anxiety and decompression
An \u3cem\u3eFTO\u3c/em\u3e Gene Variant Moderates the Association between Parental Restriction and Child BMI
Objective:
This study aimed to explore whether a common variant in the FTO gene moderates the relationship between parental restriction and child BMI.
Methods:
This study reports on baseline data from 178 parent-child (ages 9–10 years) dyads. Parents completed the Child Feeding Questionnaire and reported on socio-demographic characteristics. Each child’s height, weight and FTO rs9939609 genotype was assessed. Ordinary least squares regression was used to fit the child’s BMI-percentile on parental restriction and the child’s FTO genotype, adjusted for covariates. A likelihood ratio test was used to compare a model with and without a multiplicative interaction term between restriction and genotype.
Results:
Most participants (93.3%) were white, non-Hispanic. Twenty-three percent of children were overweight/obese and FTO genotype was associated with weight status. Mean parental restriction was statistically higher among overweight/obese vs. normal weight children: 3.3 (SD 0.8) vs. 2.8 (SD 1.0); t-test p-value = 0.002. Parental restriction was positively associated with child BMI-percentile and BMI-z only among children with two copies of the high-risk FTO allele (p for interaction = 0.02), where each one-point increase in parental restriction was associated with a 14.7 increase in the child’s BMI-percentile or a 0.56-point increase in the child’s BMI z-score.
Conclusion:
For only the children with two high-risk alleles, parental restriction was positively associated with child BMI-percentile
Evaluating the Effects of Cerebrospinal Fluid Protein Content on the Performance of Differential Pressure Valves and Antisiphon Devices Using a Novel Benchtop Shunting Model
BACKGROUNDHydrocephalus is managed by surgically implanting flow-diversion technologies such as differential pressure valves and antisiphoning devices; however, such hardware is prone to failure. Extensive research has tested them in flow-controlled settings using saline or de-aerated water, yet little has been done to validate their performance in a setting recreating physiologically relevant parameters, including intracranial pressures, cerebrospinal fluid (CSF) protein content, and body position.OBJECTIVETo more accurately chart the episodic drainage characteristics of flow-diversion technology. A gravity-driven benchtop model of flow was designed and tested continuously during weeks-long trials.METHODSUsing a hydrostatic pressure gradient as the sole driving force, interval flow rates of 6 valves were examined in parallel with various fluids. Daily trials in the upright and supine positions were run with fluid output collected from distal catheters placed at alternating heights for extended intervals.RESULTSSignificant variability in flow rates was observed, both within specific individual valves across different trials and among multiple valves of the same type. These intervalve and intravalve variabilities were greatest during supine trials and with increased protein. None of the valves showed evidence of overt obstruction during 30 d of exposure to CSF containing 5 g/L protein.CONCLUSIONDay-to-day variability of ball-in-cone differential pressure shunt valves may increase overdrainage risk. Narrow-lumen high-resistance flow control devices as tested here under similar conditions appear to achieve more consistent flow rates, suggesting their use may be advantageous, and did not demonstrate any blockage or trend of decreasing flow over the 3 wk of chronic use
Can it be harmful for parents to talk to their child about their weight? A meta-analysis
Many parents express concern that raising the issue of weight risks harming their child's physical self-perceptions and wellbeing. Such concerns can deter families from engaging with weight management services. This systematic review aimed to investigate the evidence behind these concerns by analysing the association between parent-child weight-talk and child wellbeing. A systematic search of eight databases identified four intervention studies and 38 associative studies. Meta-analysis was only possible for the associative studies; to facilitate more meaningful comparisons, weight-talk was categorized into four communication types and effect size estimates for the association between these and wellbeing indicators were calculated through a random effects model. Encouraging children to lose weight and criticizing weight were associated with poorer physical self-perceptions and greater dieting and dysfunctional eating (effect sizes: 0.20 to 0.47). Conversely, parental encouragement of healthy lifestyles without explicit reference to weight was associated with better wellbeing, but this was only measured in two studies. Of the four intervention studies, only one isolated the effects of parents' communication on wellbeing outcomes, reporting a positive effect. There was no effect of age on the strength of associations, but dysfunctional eating was more strongly associated with parent communication for girls than boys. The findings indicate that some forms of parent-child weight-talk are associated with poor wellbeing, but suggest that this is not inevitable. Encouraging healthy behaviours without reference to weight-control, and positive parental involvement in acknowledging and addressing weight-concern may avoid such outcomes. More longitudinal research is needed to analyse the direction of these effects
Oxytocin Receptor Genotype Modulates Ventral Striatal Activity to Social Cues and Response to Stressful Life Events
Velocity and wall shear measurements inside a vascular graft model under steady and pulsatile flow conditions
Ph.D.Don P. Gidden
The Influence of Coughing on Cerebrospinal Fluid Pressure in an in Vitro Syringomyelia Model with Spinal Canal Stenosis
Five in vitro models were constructed which were representative of various pathologies of the spinal canal (SC) associated with syringomyelia (SM). The models were subjected to a cough type flow impulse while monitoring the pressure environment in the syrinx and subarachnoid space (SAS) regions of the model. The results indicated that conditions can arise during a cough which would provide pressure forces to encourage cerebrospinal fluid (CSF) movement into the syrinx cavity
- …